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1

Current Developments and Prospective of Lead-Free Piezoelectric Ceramics  

NASA Astrophysics Data System (ADS)

The dielectric, ferroelectric and piezoelectric properties of perovskite ferroelectric and bismuth layered-structured ferroelectric (BLSF) ceramics are described being superior candidates for lead-free piezoelectric materials to reduce environmental damage. Perovskite-type ceramics seem to be suitable for actuator and high-power applications that require a large piezoelectric constant, d33, and a high Curie temperature, Tc, or a depolarization temperature, Td (>200 C). For BaTiO3-based solid solutions, (1-x)BaTiO3-x(Bi0.5K0.5)TiO3 (BT-BKT100x) ceramics, Tc increases with increasing amount of x. The BT-BKT20 + MnCO3 (0.1 wt %) ceramic shows a high Tc greater than 200 C and an electromechanical coupling factor of k33 =0.35. In the case of a(Bi1/2Na1/2)TiO3-b(Bi1/2K1/2)TiO3-cBaTiO3 [BNBK (100a/100b/100c)] solid solution ceramics, d33 is 191 pC/N for BNBK (85.2/2.8/12). KNbO3 (KN)-based ceramics are also a candidate for lead-free piezoelectrics. In Mn-doped KN ceramics, a higher k33 of 0.507 is obtained for KN + MnCO3 (0.1 wt %). On the other hand, BLSF ceramics seem to be excellent candidates as piezoelectric sensors for high temperatures and ceramic resonators with a high mechanical quality factor, Qm, and a low temperature coefficient of resonance frequency, TC-f. The k33 value of the donor (Nb)-doped and grain-oriented (HF) Bi4Ti3-xNbxO12 (BITN-x) ceramic is 0.39 for x=0.08 and is able to keep the same stable value up to 350 C. Nd(0.01) and V(0.75) co-doped Bi4Ti3O12 ceramics, BNTV(0.01, 0.75), show a relatively low TC-f. Bi3TiTaO9 (BTT)-based solid solution, Srx-1Bi4-xTi2-xTaxO9 [SBTT2(x)] (1?q x?q 2), displays the high Qm value (=13500) in (p)-mode at x=1.25. For resonator applications, (Sr1-xCax)2Bi4Ti5O18 (SCBT) (0?q x?q 0.5) ceramics are suitable.

Takenaka, Tadashi; Nagata, Hajime; Hiruma, Yuji

2008-05-01

2

Domain evolution in lead-free thin film piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

Due to environmental and health concerns lead-free piezoelectric systems are currently being evaluated for use as replacements for lead-based ceramics. (1-x)Na0.5Bi0.5TiO3 - xBaTiO3 (NBT-xBT) is a promising alternative. In order to develop materials with improved performance, it is necessary to understand local structure effects on the piezoelectric response at the grain level. Using piezoresponse force microscopy (PFM), we have studied the domain evolution under locally applied electric fields. Using pulsed laser deposition thin films are deposited on Pt/Ti/SiO2/Si substrates at a temperature of 650 C in a 150 mTorr O2 environment. In NBT-0.05BT films, domains are clearly visible after the application of a bias field and they relax after a period of time. After the films are exposed to ambient conditions for several weeks, they must be annealed before domains are again visible with PFM. Domain images after poling indicate that the polarization direction is rotating in the plane of the sample.

Rogers, Meredith E.; Fancher, Chris M.; Blendell, John E.

2012-09-01

3

Study of nickel inner electrode lead-free piezoelectric ceramics  

Microsoft Academic Search

A (K,Na)NbO3 (KNN)-based multilayer piezoelectric ceramic with nickel inner electrodes was successfully fabricated by co-firing in a reducing atmosphere. We studied the compositional modification of KNN in order to increase reducing resistance in the sintering process, and obtained a good composition by using a solid solution with CaZrO3. A multilayer ceramic specimen had a ratio between the strain and induced

S. Kawada; M. Kimura; H. Hayashi; K. Ogiso; T. Konoike; H. Takagi

2011-01-01

4

Structural, Dielectric, Piezoelectric and Ferroelectric Characterization of NBT-BT Lead-Free Piezoelectric Ceramics  

NASA Astrophysics Data System (ADS)

Lead free piezoelectric 0.94(Na0.5Bi0.5)TiO3-0.06BaTiO3 (NBT-BT) ceramics were synthesized in MPB composition by conventional solid state reaction method. The crystalline nature of NBT-BT ceramic was studied by XRD and the size of the grains are determined by SEM. The X- ray diffraction results reveal that Ba2+ diffuse into the Na0.5 Bi0.5TiO3 lattices to form a solid solution with a pure perovskite structure. Because of the strong ferroelectricity and MPB, the ceramics exhibit high piezoelectric properties: d33 = 206 pC/N. Td (depolarization temperature) and Tm (temperature at with the dielectric constant epsilonr reaches a maximum) were observed through the phase transition in dielectric studies. In addition, the prepared ceramic exhibits relaxor characteristic, which probably results from the cation disordering in the 12fold coordination sites. Pr and Ec of the prepared ceramics were determined from the P-E hysteresis loop.

Shanmuga Sundari, S.; Kumar, Binay; Dhanasekaran, R.

2013-05-01

5

Structure, microstructure, and piezoelectric properties of ytterbium-doped potassium sodium niobate lead-free ceramics  

NASA Astrophysics Data System (ADS)

The structure, microstructure, and piezoelectric properties of conventionally sintered Yb-doped K0.5Na0.5NbO3 (KNN) lead-free ceramics were investigated. Doping the KNN ceramics with Yb2O3 was effective in inhibiting the grain growth in the KNN ceramics and in densifying the ceramics. The 1.0 wt. % Yb-doped KNN ceramics showed the maximum density, about 96.8% of the theoretical density. X-ray diffraction analysis showed that a small number of Yb3+ ions could be incorporated into the matrix of the ceramicsto occupythe ?- or ?-sites in the crystal lattice, thereby significantly affecting the piezoelectric properties of the ceramics. Enhanced piezoelectric properties ( i.e., d 33= 135 pC/N, k p = 34.5%, and Q m = 80.2) were obtained for the 0.50 wt. % Yb-doped KNN ceramics.

Li, Huan; Yang, Wenlong; Zhou, Zhongxiang; Tian, Hao

2013-09-01

6

Preparation of lead free KNLNTS piezoelectric ceramics by molten salt synthesis and its application  

Microsoft Academic Search

Lead-free (K0.44Na0.52Li0.04)(Nb0.86Ta0.10Sb0.04)O3 (KNLNTS) piezoelectric ceramics were synthesized by the NaCl-KCl (NaCl\\/KCl=1\\/1) molten salt synthesis (MSS) method. The KNLNTS ceramics was fabricated successfully by sintering at 1100degC to 1200degC. The results show that the KNLNTS powder particle size increased form 50 nm to 200 nm and the shape changed from cubic structure to plated-like structure with time increasing. Compared to the

Xiang-cheng Chu; Jun-fei Wu; Long-tu Li; Liang Zhong; Shi-xi Zhao

2008-01-01

7

Lead-free piezoelectric ceramics and transducers in potassium sodium niobate-solid solution system  

NASA Astrophysics Data System (ADS)

Lead-free piezoelectric ceramic of (K0.44Na0.52Li 0.04)(Nb0.84Ta0.1Sb0.06)O 3; (KNN-LT-LS) was prepared by two processing routes, namely "Perovskite" and "Mixed oxide". The sensitivity of raw materials to relative humidity of laboratory environment indicated that the powders batching/handling had to be carried out in a controlled atmosphere (e.g. Ar). The electromechanical properties of bulk samples in which batching carried out in Ar atmosphere were significantly higher than those ceramics prepared in the laboratory environment. The electromechanical properties of ceramics were also very sensitive to the oxygen flow rate during sintering. It was realized that oxygen vacancies could be formed in low oxygen flow rate and deteriorate piezoelectric properties of such ceramics. Reduction in oxygen vacancies facilitated domain wall switching and led to higher remnant polarization with lower coercive field. The highest longitudinal coupling (k33) and piezoelectric charge (d33 ) coefficients for perovskite routes at optimized oxygen flow rate of 180cm3/min were 65% and 315pC/N, respectively. The substitution of Ba2+ (0, 0.5, 1, 1.5, and 2 mol%) ion as an A-site donor dopant to this system improved the relative permittivity, longitudinal coupling and piezoelectric charge coefficients. Increase in remnant polarization along with the decline of coercive field indicated that the addition of Ba2+ gave rise to soft characteristics in this ternary system. The effect of 0-2 mol% of copper oxide (CuO) addition to the base composition was increased the grain size and changed the morphology and growth behavior of the grains. Mechanical quality factor was remarkably improved (Qm = 350) upon addition of 2 mol% Cu2+ with dramatic decrease in amount of energy for switching the dipole moments. Single element air-backed transducers made of undoped and 1.0 mol% Ba 2+-KNN-LT-LS, and PZT-4 showed a measured -6dB fractional bandwidth of 36%, 50.4%, and 53.5%, respectively. High frequency lead-free transducer of KNN-LT-LS were also fabricated that showed the fractional bandwidth (-6dB) of 55.3% at center frequency of 23.5 MHz. This close acoustic performance of studied lead-free transducer in regards to PZT-4 transducer showed that the lead-free system could be a good candidate used for imaging and HIFU (High Focused Ultrasound) therapeutic applications.

Marandian-Hagh, Nader

8

Sodium potassium niobate-based lead-free piezoelectric ceramics: Bulk and freestanding thick films  

NASA Astrophysics Data System (ADS)

Due to the toxicity of lead, there is an urgent need to develop lead-free alternatives to replace the currently dominant lead-based piezoelectrics such as lead zirconate titanate (PZT). (Na0.5K0.5)NbO 3 (NKN)-based piezoelectrics are promising because of their relatively high Curie temperatures and piezoelectric coefficients among the non-lead piezoelectrics. However, it is difficult to sinter. In this thesis study, a colloidal coating method was developed to improve the sintering of NKN. With this coating method, NKN with good piezoelectric properties can be produced without cold isostatic pressing. To improve the piezoelectric performance of NKN, we performed antimony (Sb) doping studies for a NKN-LN solid solution using the coating approach. It was found that Sb doping greatly improved the density and the piezoelectric properties of the NKN-LiNbO3 solid solution and optimized performance was found at 4%Sb. The reasons for the improved piezoelectric properties and density were discussed. Recently, a large enhancement in the piezoelectric performance under electric fields was discovered in polycrystalline lead magnesium niobate-lead titanate (PMN-PT) when the material was made into freestanding film geometry. Here, for the first time, we show a similar effect was also observed in a lead-free system, (Na0.5K0.5)0.945Li0.055Nb 0.96Sb0.04O3. At 6-8 kV/cm, a giant --d 31 value of 1700 pm/V was achieved, 20 times higher than the value of bulk counterpart. The enhancement was found to result from the ease of domain motion imparted by the freestanding film geometry, and the magnitude of the enhancement can be affected by the electrode layer (a non-piezoelectric) thickness. The freestanding geometry provides a new approach to greatly improve the piezoelectric performance of the current lead-free systems.

Li, Huidong

9

High performance Aurivillius phase sodium-potassium bismuth titanate lead-free piezoelectric ceramics with lithium and cerium modification  

NASA Astrophysics Data System (ADS)

The piezoelectric properties of the lithium and cerium modified A-site vacancies sodium-potassium bismuth titanate (NKBT) lead-free piezoceramics are investigated. The piezoelectric activity of NKBT ceramics is significantly improved by the modification of lithium and cerium. The Curie temperature TC, piezoelectric coefficient d33, and mechanical quality factor Qm for the NKBT ceramics modified with 0.10 mol % (LiCe) are found to be 660 C, 25 pC/N, and 3135, respectively. The Curie temperature gradually decreases from 675 to 650 C with the increase of (LiCe) modification. The dielectric spectroscopy shows that all the samples possess stable piezoelectric properties, demonstrating that the (LiCe) modified NKBT-based ceramics are the promising candidates for high temperature applications.

Wang, Chun-Ming; Wang, Jin-Feng

2006-11-01

10

Lead Free Piezoelectric Materials  

Microsoft Academic Search

Lead oxide based ferroelectrics, represented by lead zirconate titanate (Pb(Zr, Ti)O3) or PZT) are the most widely used materials for piezoelectric actuators, sensors and transducers due to their excellent piezoelectric properties. Considering lead toxicity, there is interest in developing piezoelectric materials that are biocompatible and environmentally friendlier. The low density of non-lead based materials can also be an advantage in

M. Demartin Maeder; D. Damjanovic; N. Setter

2004-01-01

11

High magnetoelectric effect in laminated composites of giant magnetostrictive alloy and lead-free piezoelectric ceramic  

NASA Astrophysics Data System (ADS)

Magnetoelectric (ME) laminated composites with all phases environmentally friendly were prepared by sandwiching one layer of thickness-polarized (Bi1/2Na1/2)TiO3-(Bi1/2K1/2)TiO3-BaTiO3 lead-free piezoelectric ceramic disk between two layers of thickness-magnetized Tb0.3Dy0.7Fe1.92 giant magnetostrictive alloy disk along the thickness direction. The composites exhibited the maximum ME voltage coefficient of 40.7 mV/Oe with a flat response in the measured frequency range of 0.1-20 kHz under a dc magnetic bias of 5 kOe. The induced ME voltage showed an extremely linear relationship to the applied ac magnetic field with amplitude varying from 310-5 to 10 Oe over a broad range of dc magnetic bias of 0-5.5 kOe. The high ME effect was analyzed and found to be comparable to most major lead-based ME composites. The present study opens up possibilities for developing green ME devices.

Jia, Yanmin; Or, Siu Wing; Wang, Jie; Chan, Helen Lai Wa; Zhao, Xiangyong; Luo, Haosu

2007-05-01

12

Phase transition and high piezoelectricity in (Ba,Ca)(Ti1-xSnx)O3 lead-free ceramics  

NASA Astrophysics Data System (ADS)

The phase structure in the (Ba,Ca)(Ti1-xSnx)O3 lead-free ceramics was evolved from inceptive orthorhombic (O) at 0 <= x <= 0.04 to a two-phase coexistence of pseudocubic-orthorhombic (PC-O) at 0.06 <= x <= 0.10 and further to a multiphase coexistence of rhombohedral-pseudocubic-orthorhombic (R-PC-O) at x = 0.11. Due to the multiphase coexistence of R-PC-O at room temperature proved by X-ray diffraction, dielectric constant ?r and differential scanning calorimetry, an ultrahigh piezoelectric coefficient d33 = 670 pC/N and electrostrain 0.061% were achieved. The high d33 over 520 pC/N was stabilized in a wide compositional range of 0.07 <= x <= 0.11, suggesting that (Ba,Ca)(Ti,Sn)O3 ceramics are a promising candidate for the lead-free piezoelectric ceramics.

Zhu, Li-Feng; Zhang, Bo-Ping; Zhao, Xiao-Kun; Zhao, Lei; Yao, Fang-Zhou; Han, Xi; Zhou, Peng-Fei; Li, Jing-Feng

2013-08-01

13

Piezoelectric Properties of LiSbO3-Modified (K0.48Na0.52)NbO3 Lead-Free Ceramics  

NASA Astrophysics Data System (ADS)

Lead-free piezoelectric (1-x)(K0.48Na0.52)NbO3-xLiSbO3 [(1-x)KNN-xLS] ceramics were prepared by conventional sintering. A morphotropic phase boundary (MPB) between the orthorhombic and tetragonal phases was identified in the composition range of 0.04ceramics near the MPB exhibit a strong compositional dependence, and good piezoelectric properties, temperature stability, and aging characteristics. It was found that the samples with 5 mol % LS exhibited enhanced electrical properties (d33 262 pC/N, kp 46%, Tc 373 C, To--t 60 C). These results show that (1-x)KNN-xLS ceramic is a promising lead-free piezoelectric material.

Wu, Jiagang; Wang, Yuanyu; Xiao, Dingquan; Zhu, Jianguo; Yu, Ping; Wu, Lang; Wu, Wenjuan

2007-11-01

14

Lead free (K,Na)NbO3-based piezoelectric ceramics and transducers  

Microsoft Academic Search

Recent advances in (K,Na)NbO3-based ferroelectrics is reviewed, with special emphasis on the (K,Na)NbO3-LiTaO3-LiSbO3 system. Processing issues are elaborated on. The importance of precursor purity, moisture sensitivity and oxygen content on the dielectric and piezoelectric properties will be shown. Properties of prototype transducers are given and it will be shown that high performance metrics reminiscent to PZT-4 based transducers can be

K. Kerman; M. Abazari; N. Marandian-Hagh; E. K. Akdogan; A. Safari

2008-01-01

15

Correlation between Phase Transitions and Piezoelectric Properties in Lead-Free (K,Na,Li)NbO3-BaTiO3 Ceramics  

NASA Astrophysics Data System (ADS)

In this manuscript, we report the polymorphic phase transitions, structural changes and piezoelectric properties of alkali niobate based lead-free ceramics. The phase transitions were characterized as a function of alkali niobate content at room temperature. The results clearly demonstrate that in this system high piezoelectric properties are achieved for a specific fraction of ferroelectric orthorhombic (O) and tetragonal (T) phases. Using Rietveld and powder diffraction analysis, a correlation was established among the piezoelectric response, the fraction of O and T phases, and KNN ratio for three different systems of (K,Na)NbO3-BaTiO3 (KNN-BT), KNN-LiNbO3 (LN), and (K,Na,Li)NbO3 (KNLN)-BT.

Ahn, Cheol-Woo; Park, Chee-Sung; Viehland, Dwight; Nahm, Sahn; Kang, Dong-Heon; Bae, Kyoo-Sik; Priya, Shashank

2008-12-01

16

Manufacture and Cytotoxicity of a Lead-free Piezoelectric Ceramic as a Bone Substitute--Consolidation of Porous Lithium Sodium Potassium Niobate by Cold Isostatic Pressing  

PubMed Central

Aim The piezoelectric properties and cytotoxicity of a porous lead-free piezoelectric ceramic for use as a direct bone substitute were investigated. Methodology Cold isostatic pressing (CIP) was applied to fabricate porous lithium sodium potassium niobate (Li0.06Na0.5K0.44) NbO3 specimens using a pore-forming method. The morphologies of the CIP-processed specimens were characterized and compared to those of specimens made by from conventional pressing procedures. The effects of the ceramic on the attachment and proliferation of osteoblasts isolated from the cranium of 1-day-old Sprague-Dawley rats were examined by a scanning electron microscopy (SEM) and methylthiazol tetrazolium (MTT) assay. Results The results showed that CIP enhanced piezoelectricity and biological performance of the niobate specimen, and also promoted an extracellular matrix-like topography of it. In vitro studies showed that the CIP-enhanced material had positive effects on the attachment and proliferation of osteoblasts. Conclusion Niobate ceramic generated by CIP shows a promise for being a piezoelectric composite bone substitute.

Wang, Qi; Yang, Jun; Zhang, Wu; Khoie, Roxanne; Li, Yi-ming; Zhu, Jian-guo; Chen, Zhi-qing

2009-01-01

17

Influence of sintering temperature on piezoelectric properties of (K 0.4425 Na 0.52 Li 0.0375 )(Nb 0.8925 Sb 0.07 Ta 0.0375 )O 3 lead-free piezoelectric ceramics  

Microsoft Academic Search

Microstructure characteristics, phase transition, and electrical properties of (K0.4425Na0.52Li0.0375) (Nb0.8925Sb0.07Ta0.0375)O3 (KNLNST) lead-free piezoelectric ceramics prepared by normal sintering were investigated with an emphasis on the influence\\u000a of sintering temperature. The microstructure and piezoelectric, ferroelectric, and dielectric properties were investigated,\\u000a with a special emphasis on the influence of sintering temperature from 1,100 to 1,140C. Orthorhombic phases mainly exist\\u000a in the ceramics

Xuming Pang; Jinhao Qiu; Kongjun Zhu; Bin Shao

18

Improved Process for Hydrothermal Lead-Free Piezoelectric Powders and Performances of Sintered (K0.48Na0.52)NbO3 Ceramics  

NASA Astrophysics Data System (ADS)

In this study, we report some improvements in a hydrothermal method for lead-free piezoelectric powders and the performance of the sintered (K0.48Na0.52)NbO3 ceramics. To increase the obtained powder weight per source solution volume, the hydrothermal reaction conditions were modified. This improvement is important for mass production; however, it resulted in a larger particle size dispersion. Therefore, we examined to introduced the ball milling process that is useful for dense (K0.48Na0.52)NbO3 ceramics. When a large amount of powder was obtained, it took a long time to eliminate the residual alkaline ions in the hydrothermal powders by a washing process. Therefore, a neutralization was conducted in the powder washing process. Using this powder, a solid solution of (K,Na)NbO3 ceramics was synthesized. The relative density was successfully increased. Concerning the electrical properties, the relative permittivity was improved, and the piezoelectric constant d33 was also increased from 114 to 130 pC/N.

Maeda, Takafumi; Hemsel, Tobias; Morita, Takeshi

2011-07-01

19

Enhanced piezoelectricity and nature of electric-field induced structural phase transformation in textured lead-free piezoelectric Na0.5Bi0.5TiO3-BaTiO3 ceramics  

NASA Astrophysics Data System (ADS)

This letter provides a comparative description of the properties of textured and randomly oriented poly-crystalline lead-free piezoelectric 0.93(Na0.5Bi0.5TiO3)-0.07BaTiO3 (NBT-BT) ceramics. A high longitudinal piezoelectric constant of (d33) ~ 322 pC/N was obtained in (001)PC textured NBT-7BT ceramics, which is almost ~2 times the d33 coefficient reported for randomly oriented ceramics of the same composition. In situ neutron diffraction experiments revealed that characteristically different structural responses are induced in textured and randomly oriented NBT-BT ceramics upon application of electric fields (E), which are likely related to the varying coherence lengths of polar nanoregions and internal stresses induced by domain switching.

Maurya, Deepam; Pramanick, Abhijit; An, Ke; Priya, Shashank

2012-04-01

20

Large Piezoelectric Constant and High Curie Temperature of Lead-Free Piezoelectric Ceramic Ternary System Based on Bismuth Sodium Titanate-Bismuth Potassium Titanate-Barium Titanate near the Morphotropic Phase Boundary  

Microsoft Academic Search

A lead-free piezoelectric ceramic ternary system based on bismuth sodium titanate, (Bi1\\/2Na1\\/2)TiO3 (BNT) - bismuth potassium titanate (Bi1\\/2K1\\/2)TiO3 (BKT) - barium titanate BaTiO3 (BT) near the morphotropic phase boundary (MPB) between the tetragonal and rhombohedral phases has been investigated. In the case of a(Bi1\\/2Na1\\/2)TiO3-bBaTiO3-c(Bi1\\/2K1\\/2)TiO3 [BNBK(100a\\/100b\\/100c)] solid solution ceramics, the highest piezoelectric constant d33=191 pC\\/N, Curie temperature, Tc=301C, electromechanical coupling factor,

Hajime Nagata; Masaki Yoshida; Yoichi Makiuchi; Tadashi Takenaka

2003-01-01

21

Properties of non-stoichiometric 0.935(K0.5+xNa0.5+x)NbO3-0.065LiSbO3 lead-free piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

0.935(K0.5+xNa0.5+x)NbO3-0.065LiSbO3 lead-free piezoelectric ceramics were prepared by normal sintering, and their piezoelectric and dielectric properties were investigated by varying the compensating amount x of alkaline elements (Na and K) addition. It was found that the crystal structure changed from tetragonal to orthorhombic with increasing x from -0.010 to 0.010. An MPB was tailored by optimizing the alkaline elements contents. Enhanced electrical and electromechanical responses of d33=253 pC/N, kp=0.47, kt=0.45 and tan?=0.027 were obtained in the ceramics with x=0.005. These excellent piezoelectric and electromechanical properties indicate that this system may be an attractive lead-free material for a wide range of electro-mechanical transducer applications.

Du, Juan; Zang, Guo-Zhong; Xiu-Jie, Yi; Wei, Yan-Yan; Wang, Yue-Fang

2012-02-01

22

Lead-free piezoelectric ceramics of (Bi1\\/2Na1\\/2)TiO3-BaTiO3-BiFeO3 system  

Microsoft Academic Search

Bismuth sodium titanate, (Bi1\\/2Na1\\/2)TiO3 (BNT)-based solid solution, a(Bi1\\/2Nal\\/2)TiO3-bBaTiO3-cBiFeO3, [BNBTF(100a\\/100b\\/100c)], was studied for its dielectric, ferroelectric and piezoelectric properties, as a new group of lead-free piezoelectric ceramics. Curie temperatures, Tc. of the BNBTF ceramics shift to the higher temperature with an increasing amount of modified Bi ion, and temperature dependence of the resonance frequencies, fr is smaller with increasing amount of

Hajime Nagata; Nobuhiro Koizumi; Nobuhisa Kuroda; Isao Igarashi; Tadashi Takenaka

1999-01-01

23

Piezoelectric Properties of Lead-Free Na0.5K0.5NbO3 Ceramics Co-Doped with NiO and CuO  

Microsoft Academic Search

Lead-free Na0.5K0.5NbO3 + 0.5 mol% NiO+y mol% CuO (y = 0?3) piezoelectric ceramics have been prepared by conventional solid state reaction technique. The crystal structure and microstructure were analyzed using X-ray diffraction and scanning electron microscopy, respectively. The results indicated that the co-doping of NiO and CuO was very effective in densification of ceramics. The KNN ceramics co-doped with 0.5mol%

Weon-Pil Tai; Young-Hyeok Kim; Yun-Po Ok; Han-Na Ji; Sang-Kyu Kang; Jae-Shin Lee

2010-01-01

24

Microstructure and electrical properties of La-modified K0.5Na0.5NbO3 lead-free piezoelectric ceramics  

Microsoft Academic Search

Lead-free ceramics (K0.5Na0.5)1-3xLaxNbO3 (0 <= x <= 0.0175) have been fabricated by a conventional sintering technique. The results of XRD show that the ceramics possess a perovskite structure with orthorhombic symmetry. Moreover, doping inhibits the grain growth, decreases the ferroelectric-paraelectric phase transition temperature and induces a diffuse phase transition. At low doping levels (x <= 0.0075), the observed remanent polarization

Daojiang Gao; K. W. Kwok; Dunmin Lin; H. L. W. Chan

2009-01-01

25

Electrical Properties and Depolarization Temperature of (Bi1/2Na1/2)TiO3-(Bi1/2K1/2)TiO3 Lead-free Piezoelectric Ceramics  

NASA Astrophysics Data System (ADS)

The piezoelectric properties of a solid solution of the binary system, x(Bi1/2Na1/2)TiO3-(1-x)(Bi1/2K1/2)TiO3 [BNKT100x; x=0.50--0.98] were investigated, focusing on depolarization temperature, Td. Fine piezoelectric properties in lead-free piezoelectric ceramics were obtained near the morphotropic phase boundary (MPB) composition between the rhombohedral and tetragonal structures, and the highest electromechanical coupling factor, k33, and piezoelectric constant, d33, were 0.56 for BNKT84 and 157 pC/N for BNKT80, respectively. However, the Td of BNKT80 was low (174 C). The Td of the MPB composition was low, and the Td near the MPB composition was sharply decreased. It is thought that BNKT70 is a candidate composition for lead-free actuator applications owing to its relatively large piezoelectric constant, d33 (126 pC/N), dynamic d33 (214 pm/V), and high depolarization temperature, Td (206 C). In this study, we determined depolarization temperature, Td, from the temperature dependence of dielectric and piezoelectric properties.

Yoshii, Kazushige; Hiruma, Yuji; Nagata, Hajime; Takenaka, Tadashi

2006-05-01

26

Formation of Morphotropic Phase Boundary in (Na0.5K0.5)NbO3--BaZrO3--(Bi0.5Li0.5)TiO3 Lead-Free Piezoelectric Ceramics  

NASA Astrophysics Data System (ADS)

For the development of lead-free piezoelectric ceramics, which have a tetragonal--rhombohedral morphotropic phase boundary (MPB), 0.90(Na0.5K0.5)NbO3--xBaZrO3--(0.10 - x)(Bi0.5Li0.5)TiO3 ceramics have been synthesized by the conventional solid state reaction method. A phase diagram was summarized from the X-ray diffraction pattern and the dielectric measurements. It is found that 0.90(Na0.5K0.5)NbO3--xBaZrO3--(0.10 - x)(Bi0.5Li0.5)TiO3 ceramics have an MPB between x = 0.07 and 0.08. In the vicinity of the MPB, it was observed that the dielectric and piezoelectric properties were enhanced.

Zushi, Junta; Ariizumi, Takuma; Kojima, Seiji; Wang, Ruiping; Bando, Hiroshi

2013-07-01

27

Microstructural origin for the piezoelectricity evolution in (K0.5Na0.5)NbO3-based lead-free ceramics  

NASA Astrophysics Data System (ADS)

Chemically modified (K0.5Na0.5)NbO3 compositions with finely tuned polymorphic phase boundaries (PPBs) have shown excellent piezoelectric properties. The evolution of the domain morphology and crystal structure under applied electric fields of a model material, 0.948(K0.5Na0.5)NbO3-0.052LiSbO3, was directly visualized using in situ transmission electron microscopy. The in situ observations correlate extremely well with measurements of the electromechanical response on bulk samples. It is found that the origin of the excellent piezoelectric performance in this lead-free composition is due to a tilted monoclinic phase that emerges from the PPB when poling fields greater than 14 kV/cm are applied.

Guo, Hanzheng; Zhang, Shujun; Beckman, Scott P.; Tan, Xiaoli

2013-10-01

28

Lead-free ceramics for pyroelectric applications  

NASA Astrophysics Data System (ADS)

The use of lead-free materials has recently become a very important issue in environmental protection of the earth. Two groups of lead-free ceramics, (K0.5,Na0.5)NbO3 based (KNN) and Bi1-y(NaxK1-x)yTiO3 based (BNKT), were studied for their thermal, dielectric, and pyroelectric properties as candidates for pyroelectric sensor applications. The BNKT-based ceramic, [Bi0.5(Na0.94K0.05Li0.016)0.5]0.95Ba0.05TiO3 (BNKLBT), shows excellent pyroelectric properties when compared with KNN-based ceramic and lead zirconate titanate. Its properties were measured as follows: pyroelectric coefficient p=360 ?C/m2 K, pyroelectric figure of merit of current, voltage, and detectivity Fi=221 pm/V, Fv=0.030 m2/C, and Fd=14.8 ?Pa-1/2. With these outstanding pyroelectric properties, the BNKLBT ceramic can be a promising material for pyroelectric sensor applications. The BNKLBT ceramic with different thicknesses (i.e., 0.3, 0.5, and 0.7 mm) have been used as the sensing element for fabricating infrared detectors. The current responsivity of the sensors was evaluated as functions of frequency.

Lau, S. T.; Cheng, C. H.; Choy, S. H.; Lin, D. M.; Kwok, K. W.; Chan, H. L. W.

2008-05-01

29

Morphotropic phase boundary and electric properties in (1-x)Bi0.5Na0.5TiO3-xBiCoO3 lead-free piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

Lead-free (1-x)Bi0.5Na0.5TiO3-xBiCoO3 (x = 0, 0.015, 0.025, 0.03, 0.035, 0.04, and 0.06) piezoelectric ceramics have been synthesized and their structure and electric properties have been investigated systemically. The rhombohedral-tetragonal morphotropic phase boundary (MPB) locates near x = 0.025-0.035. For the ceramics with x = 0.025, the saturated polarization (Ps), remnant polarization (Pr), coercive field (Ec), strain(S), piezoelectric constant (d33), and thickness electromechanical coupling factor (kt) are 40.6 ?C/cm2, 35.4 ?C/cm2, 5.25 kV/mm, 0.11%, 107pC/N, and 0.45, respectively. The low temperature humps of relative dielectric constant, which is indicative of TR-T, are becoming inconspicuous gradually with the increasing x and almost disappear at x = 0.04. The depolarization temperature Td decreases first and then increases with the increasing x. Our results may be helpful for further work on Bi0.5Na0.5TiO3-based lead-free piezoelectric ceramics.

Guo, Fei-Fei; Yang, Bin; Zhang, Shan-Tao; Liu, Xiao; Zheng, Li-Mei; Wang, Zhu; Wu, Feng-Min; Wang, Da-Li; Cao, Wen-Wu

2012-06-01

30

Properties of Miniature Cantilever-Type Ultrasonic Motor Using Lead-Free Array-Type Multilayer Piezoelectric Ceramics of (Sr,Ca)2NaNb5O15 under High Input Power  

NASA Astrophysics Data System (ADS)

The properties of miniature cantilever-type ultrasonic motors using lead-free array-type multilayer piezoelectric ceramics of (Sr,Ca)2NaNb5O15 (SCNN) developed using the design rule were investigated under high input power by comparison with the high-power properties of SCNN ceramics. The frequency dependence of the revolution speed reflected the nonlinear behavior of SCNN ceramics with the hard-spring effect and showed a mirror-reversed image relative to that of the motor of Pb(Zr,Ti)O3 (PZT) ceramics. The output power increased linearly with increasing input power up to 110 mW without heat generation, and the driving properties were almost the same as the expectations under low input power. The output power density characteristics of the motors were high in comparison with those of the commercialized motors of PZT ceramics. It appeared that the motors have a high potential as an environmental friendly piezoelectric device with excellent properties, reflecting the high-power properties of SCNN ceramics.

Doshida, Yutaka; Shimizu, Hiroyuki; Mizuno, Youich; Tamura, Hideki

2012-07-01

31

FAST TRACK COMMUNICATION: Polymorphic phase transition and enhanced piezoelectric properties of LiTaO3-modified (Na0.52K0.48) (Nb0.93Sb0.07)O3 lead-free ceramics  

NASA Astrophysics Data System (ADS)

Lead-free (Na0.52K0.48-x)(Nb0.93-xSb0.07)O3-xLiTaO3 (NKNS7-xLT) solid solution piezoelectric ceramics were investigated in terms of their phase transition behaviour and various electrical properties. The polymorphic phase transition of NKNS7 compositions with an orthorhombic structure was shifted downwards with the addition of a small amount of LT; however, the tetragonal ferroelectric to cubic paraelectric phase transition was moved slightly upwards. The polymorphic phase boundary between the orthorhombic and the tetragonal phases was thus formed near room temperature among the compositions with 0.03 <= x <= 0.0375 where enhanced piezoelectric and electromechanical properties were achieved. The compositions close to the tetragonal side exhibit better piezoelectric properties and temperature stability. The optimum electrical properties of d33 = 362 pC N-1, kp = 53%, \\varepsilon _{33}^T =2165 , Qm = 37 and Tc = 271 C were obtained in the composition with x = 0.0375. The results indicate that the materials studied could be an excellent candidate for replacing the widely used lead-based piezoelectric ceramics.

Fu, Jian; Zuo, Ruzhong; Wang, Xiaohui; Li, Longtu

2009-01-01

32

PHASE TRANSITION, DIELECTRIC AND PIEZOELECTRIC PROPERTIES OF NaNbO3-Ba0.85Ca0.15(Ti0.9Zr0.1)O3 LEAD-FREE CERAMICS  

NASA Astrophysics Data System (ADS)

A new lead-free solid solution of (1-x)NaNbO3-xBa0.85Ca0.15(Ti0.9Zr0.1)O3 was prepared by a traditional sintering method and its phase transition, dielectric and piezoelectric properties were studied. Ba0.85Ca0.15(Ti0.9Zr0.1)O3 diffuses into NaNbO3 lattices to form a new solid solution with perovskite structure. The addition of Ba0.85Ca0.15(Ti0.9Zr0.1)O3(x?0.025) transforms NaNbO3 from antiferroelectric to ferroelectric. The diffusive ferroelectric-paraelectric phase transition is induced in the ceramics with high concentration of Ba0.85Ca0.15(Ti0.9Zr0.1)O3. The ceramics with x = 0.05-0.125 possess large Pr values of 18.6-25.5 ?C/cm2. A morphotropic phase boundary between tetragonal and orthorhombic phases is formed at 0.05 < x < 0.15, leading to a significant enhancement of piezoelectric properties. The ceramic with x = 0.125 situated near the morphotropic phase boundary exhibits the optimum piezoelectric properties: d33 = 151 pC/N and kp = 31.6%.

Lei, Yuqing; Wu, Hong; Lin, Dunmin; Zheng, Qiaoji; Wu, Xiaochun; Fan, Ximing

2012-09-01

33

Temperature stability of ([Na{sub 0.5}K{sub 0.5}NbO{sub 3}]{sub 0.93}-[LiTaO{sub 3}]{sub 0.07}) lead-free piezoelectric ceramics  

SciTech Connect

A polymorphic phase transition (PPT) is often engineered into lead-free materials to generate high piezoelectric activity at room temperature, limiting their temperature stability. We report [Na{sub 0.5}K{sub 0.5}NbO{sub 3}]{sub 0.93}-[LiTaO{sub 3}]{sub 0.07} tetragonal ceramics with favorable properties over a broad temperature range due to a high Curie temperature at 447 deg. C and PPT at -15 deg. C involving a transition to a monoclinic rather than low temperature orthorhombic phase. Piezoelectric k{sub 31} and d{sub 31} coefficients varied from 0.19 to 0.14 and -53 to -33 pC/N, respectively, over the range of -15 to 300 deg. C. Strain-electric field loops provided strains of {approx}0.2% and a high-field d{sub 33} of 205 pm/V.

Skidmore, Thomas A.; Comyn, Tim P.; Milne, Steven J. [Institute for Materials Research, University of Leeds, Leeds LS2 9JT (United Kingdom)

2009-06-01

34

Effects of Li content on the phase structure and electrical properties of lead-free (Ag0.85-xLixNa0.1K0.05)NbO3 piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

Lead-free ceramics (Ag0.85-xLixNa0.1K0.05)NbO3 (ALNKN-x, x = 0-0.16) doped with 0.5 mol. % CuO were prepared by solid state reaction method under air atmosphere. The effects of Li content on the phase structure and electrical properties of the ALNKN-x ceramics were investigated. A morphotropic phase boundary (MPB) between orthorhombic and rhombohedral phases is found at x ~ 0.08-0.14. Both the ferroelectric-ferroelectric phase transition temperature (TFE) and Curie temperature (TC) shift toward higher temperatures with increasing x. Only the phase transition peak near the TC is observed when x >= 0.12. The ferroelectric phase of the ALNKN-x ceramics becomes more stable with increasing x. Furthermore, the ceramics with x = 0.12 exhibit relatively good electrical properties along with a high Curie temperature (d33 = 44 pC/N, kp = 17.7%, Pr = 14.5 C/cm2, Ec = 37.2 kV/cm, and Tc = 335 C). The results provide helpful guidance to develop new lead-free piezoelectric materials with good temperature stability.

Wu, Lang; Liu, Naiming; Zhou, Fei; Teng, Yuancheng; Li, Yuxiang

2012-03-01

35

Dielectric behavior and microstructure of (Bi1/2Na1/2)TiO3-(Bi1/2K1/2)TiO3-BaTiO3 lead-free piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

(0.95-x)(Bi1/2Na1/2)TiO3-x(Bi1/2K1/2)TiO3-0.05BaTiO3 lead-free piezoelectric ceramics (abbreviated as BNT-BKT-BT100x with x varying from 0 to 20 mol %) are prepared by a solid-state reaction process. Variation of the dielectric properties and microstructure of BNT-BKT-BT100x ceramics with BKT content is studied. The results indicate that the relative permittivity ?r and loss tangent tan ? vary with the BKT amount. Scanning electron microscope observation also indicates that BKT in high amount affects the microstructure. X-ray diffraction analysis shows that the incorporated BKT diffuses into the BNT-BT lattice to form a solid solution during sintering.

Wang, X. X.; Choy, S. H.; Tang, X. G.; Chan, H. L. W.

2005-05-01

36

Electromechanical and ferroelectric properties of (Bi1/2Na1/2)TiO3-(Bi1/2K1/2)TiO3-BaTiO3 lead-free piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

Lead-free piezoelectric ceramics (0.95-x)(Bi1/2Na1/2)TiO3-x(Bi1/2K1/2)TiO3-0.05BaTiO3 (abbreviated as BNT-BKT-BT100x, with x ranged from 0 to 20 mol %) have been studied. Effects of amount of BKT on the electrical properties and crystal structure were examined. BNT-BKT-BT5 ceramics give good performances with piezoelectric constant d33=148 pC/N, electromechanical coupling factor kp=34 %, kt=49.2 %, free permittivity ?33T/?0=700, and dissipation factor tan?=2 % at 1 kHz. Accordingly, the sample shows larger remanent polarization and lower coercive field than 0.95BNT-0.05BT ceramics. X-ray diffraction analysis shows that incorporated BKT diffuses into the BNT-BT lattice to form a solid solution during sintering, but changes the crystal structure from rhombohedral to tetragonal symmetry at higher BKT amounts.

Wang, X. X.; Tang, X. G.; Chan, H. L. W.

2004-07-01

37

Phase transitional behavior, microstructure, and electrical properties in Ta-modified [(K0.458Na0.542)0.96Li0.04] NbO3 lead-free piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

Lead-free [(K0.458Na0.542)0.96Li0.04] (Nb1-xTax)O3 ceramics were prepared by ordinary sintering technique. The effects of Ta content on the phase transitional behavior, Raman spectrum, microstructure, and dielectric, piezoelectric, and ferroelectric properties of the ceramics were investigated. X-ray diffraction results indicate that the phase structure undergoes a transition from orthorhombic to tetragonal phase with the increase in x. The small and large peaks observed in the Raman spectra can all be attributed to the internal modes of the NbO6 octahedron, and both ?5 and ?1 modes slightly shift to lower frequency numbers by increasing x. Ta substitution for Nb leads to the disappearance of the abnormal grain growth behavior, inhibits the grain growth, and improves the density of the ceramics. Increasing x leads to the different variations of dielectric constants before and after poling and makes the ceramics more relaxorlike. The proper substitution of Ta shifts the polymorphic phase transition (at To-T) to near room temperature, and a coexistence of orthorhombic and tetragonal phases is formed, which leads to significant enhancements of the electrical properties. For the ceramics with x=0.15, the electrical properties become optimum, which are as follows: piezoelectric coefficient d33=298 pC/N, electromechanical coupling coefficient kp=0.52, dielectric constant ?r=1195, dielectric loss tan ?=0.016, To-T=35 C, Curie temperature TC=366 C, remanent polarization Pr=28.68 ?C/cm2, and coercive field Ec=7.14 kV/cm. These properties are much higher than those of previously reported (K,Na,Li)(Nb,Ta)O3 systems with K:Na=1:1.

Chang, Yunfei; Yang, Zu-Pei; Ma, Difei; Liu, Zonghuai; Wang, Zenglin

2008-07-01

38

Investigation of a new lead-free Bi0.5(Na0.40K0.10)TiO3-(Ba0.7Sr0.3)TiO3 piezoelectric ceramic.  

PubMed

Lead-free piezoelectric compositions of the (1-x)Bi0.5(Na0.40K0.10)TiO3-x(Ba0.7Sr0.3)TiO3 system (when x = 0, 0.05, 0.10, 0.15, and 0.20) were fabricated using a solid-state mixed oxide method and sintered between 1,050C and 1,175C for 2 h. The effect of (Ba0.7Sr0.3)TiO3 [BST] content on phase, microstructure, and electrical properties was investigated. The optimum sintering temperature was 1,125C at which all compositions had densities of at least 98% of their theoretical values. X-ray diffraction patterns that showed tetragonality were increased with the increasing BST. Scanning electron micrographs showed a slight reduction of grain size when BST was added. The addition of BST was also found to improve the dielectric and piezoelectric properties of the BNKT ceramic. A large room-temperature dielectric constant, ?r (1,609), and piezoelectric coefficient, d33 (214 pC/N), were obtained at an optimal composition of x = 0.10. PMID:22221833

Jaita, Pharatree; Watcharapasorn, Anucha; Jiansirisomboon, Sukanda

2012-01-05

39

Magnetoelectric effect in lead-free BNKLBT ceramic/terfenol-D continue fiber composite laminates  

SciTech Connect

A magnetostrictive-piezoelectric laminated composite has been developed by sandwiching a lead-free BNKLBT ceramic plate polarized in the thickness direction between two terfenol-D continuous fiber composite plates. This lead-free magnetoelectric (ME) laminated composite has a large ME voltage sensitivity of 2.5 V/Oe at the resonance frequency of 130.9 kHz under a low magnetic bias field (H{sub Bias}) of 0.6 kOe. This work shows the potential of BNKLBT lead-free ceramics in ME sensing application.

Lo, C. Y.; Choy, S. H.; Or, S. W.; Chan, H. L. W. [Department of Applied Physics and Materials Research Centre, Hong Kong Polytechnic University, Hunghom (Hong Kong)

2010-05-15

40

Diffuse phase transition and electrical properties of lead-free piezoelectric (LixNa1-x)NbO3 (0.04 <= x <= 0.20) ceramics near morphotropic phase boundary  

NASA Astrophysics Data System (ADS)

Temperature-dependent dielectric permittivity of lead-free (LixNa1-x)NbO3 for nominal x = 0.04-0.20, prepared by solid state reaction followed by sintering, was studied to resolve often debated issue pertaining to exactness of morphotropic phase boundary (MPB) location besides structural aspects and phase stability in the system near MPB. Interestingly, a diffuse phase transition has been observed in the dielectric permittivity peak arising from the disorder induced in A-site and structural frustration in the perovskite cell due to Li substitution. A partial phase diagram has been proposed based on temperature-dependent dielectric permittivity studies. The room temperature piezoelectric and ferroelectric properties were investigated and the ceramics with x = 0.12 showed relatively good electrical properties (d33 = 28 pC/N, kp = 13.8%, Qm = 440, Pr = 12.5 ?C/cm2, Ec = 43.2 kV/cm, and Tm = 340 C). These parameter values make this material suitable for piezoelectric resonator and filter applications. Moreover, a high dielectric permittivity (?'r = 2703) with broad diffuse peak near transition temperature, and low dielectric loss (<4%) over a wide temperature range (50-250 C) found in this material may also have a potential application in high-temperature multilayer capacitors in automotive and aerospace related industries.

Mitra, S.; Kulkarni, A. R.; Prakash, Om

2013-08-01

41

Raman- and Brillouin-scattering studies on lead-free piezoelectric Bi0.5(Na0.78K0.22)0.5- x TiO3 ceramics with A-site vacancies  

NASA Astrophysics Data System (ADS)

The Raman and Brillouin spectra of lead-free piezoelectric Bi0.5(Na0.78K0.22)0.5- x TiO3 ceramics with A-site vacancies were investigated for x = 0 0.05. The Raman spectra measured at room temperature showed seven broad bands over the range of 50-1000 cm-1, reflecting strong anharmonicity, inherent A-site disorder and the resulting breakdown of the Raman selection rule. The splitting of the A1 mode near 270 cm-1 indicated that the tetragonal symmetry was maintained over the whole x range, consistent with the X-ray diffraction results. The Brillouin spectra exhibited distributed longitudinal and transverse acoustic modes, in addition to central peaks. The distributed acoustic modes were attributed to the scattering events at all scattering angles from 0 to 180 due to multiple reflections and refractions at the grain boundaries. The relaxation time obtained from fitting the broad central peak by using a Debye function exhibited a slowing-down behavior in the paraelectric phase. The formation of the central peak was attributed to the existence of nano-sized polar regions due to the anharmonic vibrations and the hopping motions of the A-site cations.

Kim, Tae Hyun; Kojima, Seiji; Ahn, Chang Won; Kim, Ill Won; Ko, Jae-Hyeon

2013-04-01

42

Piezoelectric moduli of piezoelectric ceramics  

SciTech Connect

The effective piezoelectric moduli of polycrystalline piezoelectric ceramics are calculated using a straightforward averaging method (a Voigt average) and a more rigorous effective-medium theory recently developed for piezocomposites. The effects of polarization orientation within each crystallographic domain and the shape of the domain on the effective piezoelectric moduli are presented. The effective-medium theory, which includes full coupling of the elastic and dielectric interactions, gives results in reasonable agreement with experimental ones.

Nan, C.W.; Clarke, D.R. [Univ. of California, Santa Barbara, CA (United States). Coll. of Engineering

1996-10-01

43

Incipient piezoelectrics and electrostriction behavior in Sn-doped Bi1/2(Na0.82K0.18)1/2TiO3 lead-free ceramics  

NASA Astrophysics Data System (ADS)

Dielectric, ferroelectric, piezoelectric, and strain properties of lead-free Sn-doped Bi1/2(Na0.82K0.18)1/2TiO3 (BNKT) were investigated. A crossover from a nonergodic relaxor to an ergodic relaxor state at room temperature, accompanied by a giant electric-field-induced strain, was observed at 5 at. % Sn doping. Switching dynamics monitored during a bipolar poling cycle manifested that the observed giant strain originates from incipient piezoelectricity. When Sn doping level reached 8 at. %, BNKT exhibited an electrostrictive behavior with a highly temperature-insensitive electrostrictive coefficient of Q11 = 0.023 m4 C-2.

Han, Hyoung-Su; Jo, Wook; Kang, Jin-Kyu; Ahn, Chang-Won; Won Kim, Ill; Ahn, Kyoung-Kwan; Lee, Jae-Shin

2013-04-01

44

Sintering and piezoelectric properties of lead-free (K0.38Na0.58Li0.04)(Nb0.86Ta0.10Sb0.04)O3 ceramics doped with Fe2O3  

Microsoft Academic Search

Lead-free (K0.38Na0.58Li0.04)(Nb0.86Ta0.10Sb0.04)O3 (KNLNTS) + x mol% Fe2O3 (x = 0 ~ 1) ceramics were prepared by conventional solid state reaction technique. The effect of Fe2O3 doping on the phase structure, microstructure and electrical properties of KNLNTS ceramics were studied. The addition of Fe2O3 was found to be effective in enhancing densification of KNLNTS ceramics. When x = 0.3, the piezoelectric

Yun-Po Ok; Han-Na Ji; Ki-Soo Kim; Weon-Pil Tai; Jeong-Hyeon Seol; In-Ki Hong; Jae-Shin Lee

2011-01-01

45

Lead free BNT ceramics as driving element in traveling wave type ultrasonic motor  

NASA Astrophysics Data System (ADS)

Ultrasonic motor (USM) as a new type of driving motor has many good features compared with conventional electromagnetic motor. However, due the content of Pb in the driving element piezoelectric ceramics, Pb(Zrx,Ti1-x)O3 (PZT), the application of USM will be restricted from the viewpoint of environmental requirement. In this paper lead free piezoceramics, Mn doped 0.94(Bi0.5Na0.5)TiO3 -0.06BaTiO3(BNT-BT), was used as driving element in ultrasonic motor in replacing PZT. Though the piezoelectric property of BNT-BT ceramic is inferior to that of PZT, the USM with BNT-BT driving element shows promising result and potential to replace PZT ceramic in application of ultrasonic motor.

Yu, Zuoba; Chan, Ka Cheung; Guo, Jifeng; Dai, J. Y.; Wang, Bo; Jiang, X. P.; Kwok, K. W.

2007-10-01

46

Dielectric and piezoelectric properties of Y{sub 2}O{sub 3} doped (Bi{sub 0.5}Na{sub 0.5}){sub 0.94}Ba{sub 0.06}TiO{sub 3} lead-free piezoelectric ceramics  

SciTech Connect

Y{sub 2}O{sub 3} doped lead-free piezoelectric ceramics (Bi{sub 0.5}Na{sub 0.5}){sub 0.94}Ba{sub 0.06}TiO{sub 3} (0-0.7 wt%) were synthesized by the conventional solid state reaction method, and the effect of Y{sub 2}O{sub 3} addition on the structure and electrical properties was investigated. X-ray diffraction shows that Y{sub 2}O{sub 3} diffuses into the lattice of (Bi{sub 0.5}Na{sub 0.5}){sub 0.94}Ba{sub 0.06}TiO{sub 3} to form a solid solution with a pure perovskite structure. The temperature dependence of dielectric constant of Y{sub 2}O{sub 3} doped samples under various frequencies indicates obvious relaxor characteristics different from typical relaxor ferroelectric and the mechanism of the relaxor behavior was discussed. The optimum piezoelectric properties of piezoelectric constant d{sub 33} = 137 pC/N and the electromechanical coupling factor k{sub p} = 0.30 are obtained at 0.5% and 0.1% Y{sub 2}O{sub 3} addition, respectively.

Zhou Changrong [Department of Information Material Science and Engineering, Guilin University of Electronic Technology, Guilin, Guangxi 541004 (China)], E-mail: zcr750320@yahoo.com.cn; Liu Xinyu [Department of Information Material Science and Engineering, Guilin University of Electronic Technology, Guilin, Guangxi 541004 (China); Li Weizhou [School of Resources and Environments, Guangxi University, Nanning, Guangxi 530004 (China); Yuan Changlai [Department of Information Material Science and Engineering, Guilin University of Electronic Technology, Guilin, Guangxi 541004 (China)

2009-04-02

47

Dielectric, ferroelectric, and piezoelectric properties of Nb-substituted Bi1/2(Na0.82K0.18)1/2TiO3 lead-free ceramics  

NASA Astrophysics Data System (ADS)

The effects of niobium substitution on the crystal structure and on the ferroelectric and piezoelectric properties of Bi1/2(Na0.82K0.18)1/2(Ti)O3 (BNKT) ceramics have been investigated. X-ray diffraction analyses revealed that Nb-substitution induced a phase transition from the coexistence of rhombohedral-tetragonal symmetry to pseudocubic symmetry. Accordingly, the electric-fieldinduced polarization and strain hysteresis loops indicated that Nb substitution significantly disrupted the ferroelectric order of BNKT ceramics, leading to degradations in the remnant polarization, coercive field, and piezoelectric coefficient d 33. However, the destabilization of the ferroelectric order was accompanied by a significant enhancement in the electric-field-induced strain (EFIS), which peaked at x = 0.03 with a value of 0.47%. The abnormal enhancement in the EFIS could be attributed to a phase transition from a non-polar to a polar phase under an applied electric field.

Pham, Ky-Nam; Lee, Han Bok; Han, Hyoung-Su; Kang, Jin Kyu; Lee, Jae-Shin; Ullah, Aman; Ahn, Chang-Won; Kim, Ill Won

2012-01-01

48

Structural And Electrical Analysis Of Lead Free BZT-xBCT Ceramics  

NASA Astrophysics Data System (ADS)

A comparative study of structural and electric properties of a recently discovered lead free electroceramic, Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)TiO3 or BZT-xBCT, was conducted in the entire range from x = 0 to x = 1. This novel ceramic composite is being seen as a genuine understudy for commercially one of the most widely used piezoelectric ceramic, PZT, which is facing worldwide criticism due to its lead toxicity. The new system can be very extensively used like PZT in transduction applications as sensor, actuator and ultrasonic devices apart from numerous other utilities. The XRD, SEM and Ferroelectric studies establish the structural transition and different phases as function of Zr /Ti and Ba /Ca ratios.

Bhardwaj, Chandan; Kumar, Ashvani; Kaur, Davinder

2010-12-01

49

Structural And Electrical Analysis Of Lead Free BZT-xBCT Ceramics  

SciTech Connect

A comparative study of structural and electric properties of a recently discovered lead free electroceramic, Ba(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}-x(Ba{sub 0.7}Ca{sub 0.3})TiO{sub 3} or BZT-xBCT, was conducted in the entire range from x = 0 to x = 1. This novel ceramic composite is being seen as a genuine understudy for commercially one of the most widely used piezoelectric ceramic, PZT, which is facing worldwide criticism due to its lead toxicity. The new system can be very extensively used like PZT in transduction applications as sensor, actuator and ultrasonic devices apart from numerous other utilities. The XRD, SEM and Ferroelectric studies establish the structural transition and different phases as function of Zr /Ti and Ba /Ca ratios.

Bhardwaj, Chandan; Kumar, Ashvani; Kaur, Davinder [Functional Nanomaterials Research Lab, Department of Physics and Centre of Nanotechnology, Indian Institute of Technology Roorkee, Roorkee 247667 (India)

2010-12-01

50

Dielectric behavior and microstructure of (Bi{sub 1/2}Na{sub 1/2})TiO{sub 3}-(Bi{sub 1/2}K{sub 1/2})TiO{sub 3}-BaTiO{sub 3} lead-free piezoelectric ceramics  

SciTech Connect

(0.95-x)(Bi{sub 1/2}Na{sub 1/2})TiO{sub 3}-x(Bi{sub 1/2}K{sub 1/2})TiO{sub 3}-0.05BaTiO{sub 3} lead-free piezoelectric ceramics (abbreviated as BNT-BKT-BT100x with x varying from 0 to 20 mol %) are prepared by a solid-state reaction process. Variation of the dielectric properties and microstructure of BNT-BKT-BT100x ceramics with BKT content is studied. The results indicate that the relative permittivity {epsilon}{sub r} and loss tangent tan {delta} vary with the BKT amount. Scanning electron microscope observation also indicates that BKT in high amount affects the microstructure. X-ray diffraction analysis shows that the incorporated BKT diffuses into the BNT-BT lattice to form a solid solution during sintering.

Wang, X.X.; Choy, S.H.; Tang, X.G.; Chan, H.L.W. [Department of Applied Physics and Materials Research Center, Hong Kong Polytechnic University, Hunghom Kowloon, Hong Kong (China)

2005-05-15

51

Piezoelectric Ceramics and Their Applications  

ERIC Educational Resources Information Center

|Describes the piezoelectric effect in ceramics and presents a quantitative representation of this effect. Explains the processes involved in the manufacture of piezoelectric ceramics, the materials used, and the situations in which they are applied. (GS)|

Flinn, I.

1975-01-01

52

Piezoelectric properties of KCuNbO modified (Na{sub 0.5}K{sub 0.5})NbO lead-free piezoceramics  

Microsoft Academic Search

Dense KCuNbO modified (Na{sub 0.5}K{sub 0.5})NbO (NKN:KCN) ceramics were synthesized by using conventional oxide mixing process. The maximum mechanical quality factor Q{sub m} of NKN:KCN ceramics reaches up to 1150, the piezoelectric constant d and the planar electromechanical coefficient k{sub p} still maintain relatively high levels, which are about 100 pC\\/N and 40%, respectively. Middle frequency (455 kHz) lead-free resonators

Chen Qiang; Chen Lin; Li Qishou; Yue Xi; Xiao Dingquan; Zhu Jianguo; Shi Xiaoluo; Liu Zhiqian

2007-01-01

53

Nanoscale characterization and local piezoelectric properties of lead-free KNN-LT-LS thin films  

NASA Astrophysics Data System (ADS)

We report the observation of domain structure and piezoelectric properties of pure and Mn-doped (K0.44,Na0.52,Li0.04)(Nb0.84,Ta0.1,Sb0.06)O3 (KNN-LT-LS) thin films on SrTiO3 substrates. It is revealed that, using piezoresponse force microscopy, ferroelectric domain structure in such 500 nm thin films comprised of primarily 180 domains. This was in accordance with the tetragonal structure of the films, confirmed by relative permittivity measurements and x-ray diffraction patterns. Effective piezoelectric coefficient (d33) of the films were calculated using piezoelectric displacement curves and shown to be ~53 pm V-1 for pure KNN-LT-LS thin films. This value is among the highest values reported for an epitaxial lead-free thin film and shows a great potential for KNN-LT-LS to serve as an alternative to PZT thin films in future applications.

Abazari, M.; Choi, T.; Cheong, S.-W.; Safari, A.

2010-01-01

54

Lead-free ceramic ball grid array: Thermomechanical fatigue reliability  

Microsoft Academic Search

Flip-chip carriers have become the preferred solution for high-performance, application-specific integrated circuit and microprocessor\\u000a devices. Typically, these are packaged in organic or ceramic ball grid array (BGA) packages, which cover a wide range of package\\u000a input\\/output (I\\/O) capabilities required for high-performance devices, typically, between 300 to more than 1,600 I\\/O. Recently,\\u000a there has been a move toward Pb-free solders as

Mukta Farooq; Charles Goldsmith; Ray Jackson; Gregory Martin

2003-01-01

55

Effect of Dopant on Piezoelectric Properties of Lead-Free BiFeO3--BaTiO3 Film  

Microsoft Academic Search

To realize high-performance lead-free piezoelectric materials, we have selected BiFeO3 as the rhomboheral phase material and BaTiO3 as the tetragonal phase material, following the MPB mechanism of PZT. To further improve the piezoelectric properties of BiFeO3--BaTiO3 (BFBT) thin films, we investigated the effect of dopant on the piezoelectric properties of BFBT. Considering both Shanon effective ionic radii and valence number,

Tsutomu Sasaki; Yasutoshi Hirabayashi; Hiroyuki Kobayashi; Yukio Sakashita

2011-01-01

56

Dielectric properties of lead-free BZT-KNN perovskite ceramics for energy storage.  

PubMed

Lead-free (1-x)Ba(Zr?.??Ti?.??)O?-x(K?.?Na?.?)NbO? ; x=0-0.05) (BZT-KNN) perovskite ceramics, a materials with potential applications for energy storage, are investigated. The samples are prepared by a solid-state reaction method. Powder X-ray diffraction (XRD) and scanning electron microscopy (SEM) are used to study the microstructure of the samples. Their dielectric properties and impedance spectra are reported as functions of temperature and frequency. The addition of 1?mol?% (K?.?Na?.?)NbO? to Ba(Zr?.??Ti?.??)O? improves the dielectric constant and enhances its diffuseness in a wide temperature range. The small amount of (K?.?Na?.?)NbO? is found to markedly affect the microstructure of the Ba(Zr?.??Ti?.??)O? ceramic (grain size and other characteristics) without changing the phase or crystal symmetry. In addition, we report that fine substructures in the grains, so-called sheet structures, are responsible for the dielectric properties (both diffuseness and dielectric constant) of (1-x)Ba(Zr?.??Ti?.??)O?-x(K?.?Na?.?)NbO? (x=0-0.03; especially x=0.01) ceramics. PMID:21994154

Gui, Dong-Yun; Liu, Han-Xing; Hao, Hua; Sun, Yue; Cao, Ming-He; Yu, Zhi-Yong

2011-10-17

57

Piezoelectric properties of lithium borosilicate glass ceramics  

Microsoft Academic Search

Glass ceramics in the system Li2O-SiO2-B2O3 with oriented crystallites were prepared by crystallizing the glasses in a temperature gradient. Piezoelectric and electromechanical properties of the glass ceramics are reported. Some of the compositions exhibit low temperature coefficient of resonance, comparable to LiTaO3 single crystals. Advantages of fabricating glass-ceramic piezoelectric resonators are described and the possibility of using them in surface

A. Halliyal; A. S. Bhalla; R. E. Newnham; L. E. Cross

1982-01-01

58

Compositional dependence of phase structure and electrical properties in (K0.42Na0.58)NbO3-LiSbO3 lead-free ceramics  

NASA Astrophysics Data System (ADS)

(1-x)(K0.42Na0.58)NbO3-xLiSbO3 [(1-x)KNN-xLS] lead-free piezoelectric ceramics were prepared by the conventional mixed oxide method. The compositional dependence of the phase structure and the electrical properties of the ceramics were studied. A morphotropic phase boundary (MPB) between the orthorhombic and tetragonal phases was identified in the composition range of 0.04ceramics near the MPB exhibit a strong compositional dependence and enhanced piezoelectric properties. The ceramics with 5 mol. % LS exhibit enhanced electrical properties (d33~270 pC/N, kp~47.2%, Tc~364 C , To-t=35 C, ?r~1412, tan ?~2.8%, and Pr~25.7 ?C/cm2 Ec~11.1 kV/cm) and possess low dielectric loss (<2%) at 10 and 100 kHz at high temperature (250-400 C). The low dielectric loss at high temperature is very important for high-temperature application of the ceramics. The related mechanism of the enhanced electrical properties of the ceramics was also discussed. These results show that (1-x)KNN-xLS (x=0.05) ceramic is a promising lead-free piezoelectric material.

Wu, Jiagang; Xiao, Dingquan; Wang, Yuanyu; Zhu, Jianguo; Yu, Ping; Jiang, Yihang

2007-12-01

59

Lead-free In2O3-doped (Bi0.5Na0.5)0.93Ba0.07TiO3 ceramics synthesized by direct reaction sintering  

NASA Astrophysics Data System (ADS)

Lead-free (Bi0.5Na0.5)0.93Ba0.07TiO3-x wt %In2O3 ceramics synthesized by direct reaction sintering have been studied. X-ray diffraction reveals that all (Bi0.5Na0.5)0.93Ba0.07TiO3-x wt %In2O3 ceramics are of a perovskite structure with coexistence of rhombohedral and tetragonal phases. It is found that the direct reaction sintering promotes growing of ceramic grains while doping of In2O3 contributes to inhibit and homogenize the grain growth, as shown by scanning electron microscopy. The ceramics show excellent piezoelectric and dielectric properties with thickness electromechanical coupling factor kt=0.503, piezoelectric constant d33=205 pC/N, dielectric constant ?33T/V0=1046, and loss tangent tan ?=0.036.

Zhou, Tao-Sheng; Huang, Rong-Xia; Shang, Xun-Zhong; Peng, Fei; Guo, Jian-Yong; Chai, Li-Ying; Gu, Hao-Shuang; He, Yun-Bin

2007-04-01

60

Piezoelectric measurements on ceramic multilayer capacitors  

SciTech Connect

Piezoelectric measurements are reported for a series of commercial multilayer capacitors which had been previously tested and sold for high-reliability applications. The capacitors conformed to BX specifications and were fabricated from various combinations of barium titanate based dielectric compositions with different electrode materials. Dielectric properties are reported, including distributions in capacitance values and variations in Curie-Weiss behavior. Piezoelectric measurements were made of the d/sub 13/ and d/sub 33/ coefficients; and data are reported for their distribution in values, and temperature and voltage dependencies. Significant piezoelectric coefficients were detected for capacitors in their as-received conditions. In certain cases the piezoelectric coefficients approached 1000 pC/N. The results are discussed in the context of what effects life-testing conditions may have on dielectric quality. Experiments are also reported for the electric-poling and thermal-depoling of multilayer ceramic capacitors. Concern is expressed for the over-testing of thin layer ceramic devices. Calculations indicate the strain deformation can exceed the elastic limit in certain conditions, resulting in mechanical failure. In addition, the generation of electric charge or potential by mechanical vibration contributes a significant noise to circuit applications. Voltage levels were in the millivoltage range. The study indicates that significant problems may arise in commercial ceramic multilayer capacitors due to a generally unrecognized piezoelectric effect. 5 references, 9 figures, 5 tables.

Suchicital, C.T.A.; Payne, D.A.

1985-06-01

61

Electrical properties of lead-free 0.98(Na0.5K0.5Lix)NbO3-0.02Ba(Zr0.52Ti0.48)O3 ceramics  

NASA Astrophysics Data System (ADS)

Lead-free 0.98(Na0.5K0.5Lix)NbO3-0.02Ba(Zr0.52Ti0.48)O3 piezoelectric ceramics were investigated. The experimental results show that Li content strongly affects the orthorhombic-tetragonal morphotropic phase boundary (MPB) which results in different piezoelectric properties. The phase transition composition shows a range from 0.05 to 0.1. The sample with a composition of x = 0.1 showed the maximum values of piezoelectric coefficient ( d 33= 201 ?C/N), electromechanical coupling coefficient ( k p= 39%), and remnant polarization ( P r= 21 ?C/cm2).

Lee, Seung-Hwan; Kim, Hyun-Ju; Lee, Sung-Gap; Koh, Jung-Hyuk; Baek, Sang-Don; Lee, Young-Hie

2012-02-01

62

Continuum damage mechanics in piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

Continuum damage mechanics approach is used to predict the failure of piezoelectric ceramics which are widely used as actuators and sensors in smart structures. A continuum damage model is developed for piezoelectric ceramics, and the model is used to investigate the degradation of effective properties of the material due to damage growth. Effective properties of the material are obtained by extending the Mori-Tanaka method to piezoelectric materials. A damage evolution law is proposed to predict the growth of damage with respect to time, and the involved material parameters in the damage evolution law are obtained from the experiments of Tanimoto and Okazaki. The results are obtained assuming all the effective properties of the material degrade as the damage grow, and the degradation is independent of the load history. This degradation should be taken into account to calibrate the sensors, actuators and controllers for the better reliability, maintainability and controllability of smart structures. The effective properties of the material is related to some measurable electrical quantity such as capacitance. Therefore, the state of damage can be predicted just by measuring the capacitance of the embedded piezoelectric ceramics.

Jain, Adesh K.; Sirkis, James S.

1995-05-01

63

Hydrostatic piezoelectric effect in lead titanate ceramics  

SciTech Connect

The hydrostatic piezoelectric characteristics of Pb{sub 0.955-x}Sm{sub 2x/3}Bi{sub 0.03}Ti{sub 0.98}Mn{sub 0.02}O{sub 3} ceramics were studied. Within the range of at least 25 to 70 degrees C and at high hydrostaic and uniaxial pressures of 0.1-60 MPa, a high stability of the no-load piezoelectric voltage coefficient for the material with x=0.09-0.15 was found.

Lopatin, S.S.; Lupeiko, T.G.; Zvyagintsev, B.I. [Rostov State Univ. (Russian Federation)] [and others

1994-10-01

64

High-strain piezoelectric ceramics and applications to actuators  

Microsoft Academic Search

PZT-based solid solutions are very attractive piezoelectric ceramics, because they exhibit excellent piezoelectric properties such as large piezoelectric constant. In this paper we describe the relationship between piezoelectric properties and compositions, and sintering behavior of PbNiNbTiO3PbTiO3PbZrO3 (PNNPTPZ) ceramics and applications to the microactuators for magnetic disk drives. The MPB composition was determined by the temperature dependence of the relative permittivity

Kazuaki Kurihara; Masao Kondo

2008-01-01

65

Reliability testing and data analysis of an 1657CCGA (ceramic column grid array) package with lead-free solder paste on lead-free PCBs (printed circuit boards)  

Microsoft Academic Search

In this study, the thermal cycling test of the 1657CCGA package with 95.5wt%Sn3.9wt%Ag0.6wt%Cu and 63wt%Sn37wt%Pb solder pastes on lead-free PCBs with HASL (hot-air solder leveling) CuSn, NiAu (electroless Ni and immersion Au, ENIG), and Entek OSP (organic solderability preservative) surface finishes are performed. The test stopped at 7500 cycles (0 to 100C, 40-minute cycle). The test data is best fitted

John Lau; W. Dauksher; Ed Ott; Dongkai Shangguan; Joe Smetana; Rob Horsley; Todd Castello; Dave Love; I. Menis; Bob Sullivan

2004-01-01

66

Lead-free piezoelectric ceramics based on (0.97 - x)K0.48Na0.52NbO3-0.03Bi0.5(Na0.7K0.2Li0.1)0.5ZrO3-xB0.5Na0.5TiO3 ternary system  

NASA Astrophysics Data System (ADS)

In this work, the ternary system of potassium-sodium niobate has been designed to enhance the piezoelectric properties without sacrificing the Curie temperature greatly, and (0.97 - x)K0.48Na0.52NbO3-0.03Bi0.5(Na0.7K0.2Li0.1)0.5ZrO3-xB0.5Na0.5TiO3 ceramics have been prepared by the conventional solid-state method. The effect of B0.5Na0.5TiO3 content on the microstructure and electrical properties of the ceramics is studied. The phase diagram shows a phase boundary of the rhombohedral-tetragonal (R-T) phase coexistence in the composition range of 0.5% < x < 1.5%, and then an enhanced dielectric, ferroelectric, and piezoelectric behavior is obtained at such a phase boundary zone. The ceramic with x = 0.01 has an optimum electrical behavior of d33 ~ 285 pC/N, kp ~ 0.40, ?r ~ 1235, tan ? ~ 0.031, Pr ~ 14.9 ?C/cm2, and Ec ~ 15.2 kV/cm, together with a high Curie temperature of ~347 C. The large d33 in such a ternary system is due to a composition-induced R-T phase transition and a higher ?rPr, and the thermal stability performance is strongly dependent on the phase structure. As a result, the design of the ternary system is an effective way to enhance the piezoelectric properties of potassium-sodium niobate materials.

Cheng, Xiaojing; Wu, Jiagang; Wang, Xiaopeng; Zhang, Binyu; Zhu, Jianguo; Xiao, Dingquan; Wang, Xiangjian; Lou, Xiaojie; Liang, Wenfeng

2013-09-01

67

Piezoelectric Properties of Lead-Free (Na,Bi)TiO3--BaTiO3 (001) Epitaxial Thin Films around the Morphotropic Phase Boundary  

NASA Astrophysics Data System (ADS)

The piezoelectric properties and the crystallographic nature of (1-x)(Na,Bi)TiO3--xBaTiO3 (NBT--BT) thin films around the morphotropic phase boundary (MPB) composition (x=0.05{--}0.10) were studied. NBT--BT thin films were grown epitaxially on Pt(100)/MgO(100) substrates by RF magnetron sputtering and exhibited highly (001)-oriented single-phase perovskite with a tetragonal structure. A maximum piezoelectric coefficient e31 of -14.4 C/m2 was obtained at the x = 0.07 composition of the tetragonal side near MPB (x = 0.06). These results indicate that NBT--BT thin films around the MPB are a promising lead-free replacement for Pb(Zr,Ti)O3 (PZT) based applications.

Harigai, Takakiyo; Tanaka, Yoshiaki; Adachi, Hideaki; Fujii, Eiji

2010-11-01

68

Fabrication of transparent lead-free KNN glass ceramics by incorporation method  

NASA Astrophysics Data System (ADS)

The incorporation method was employed to produce potassium sodium niobate [KNN] (K0.5Na0.5NbO3) glass ceramics from the KNN-SiO2 system. This incorporation method combines a simple mixed-oxide technique for producing KNN powder and a conventional melt-quenching technique to form the resulting glass. KNN was calcined at 800 C and subsequently mixed with SiO2 in the KNN:SiO2 ratio of 75:25 (mol%). The successfully produced optically transparent glass was then subjected to a heat treatment schedule at temperatures ranging from 525 C -575 C for crystallization. All glass ceramics of more than 40% transmittance crystallized into KNN nanocrystals that were rectangular in shape and dispersed well throughout the glass matrix. The crystal size and crystallinity were found to increase with increasing heat treatment temperature, which in turn plays an important role in controlling the properties of the glass ceramics, including physical, optical, and dielectric properties. The transparency of the glass samples decreased with increasing crystal size. The maximum room temperature dielectric constant ( ? r ) was as high as 474 at 10 kHz with an acceptable low loss (tan ?) around 0.02 at 10 kHz.

Yongsiri, Ploypailin; Eitssayeam, Sukum; Rujijanagul, Gobwut; Sirisoonthorn, Somnuk; Tunkasiri, Tawee; Pengpat, Kamonpan

2012-02-01

69

Piezoelectric nonlinearity and frequency dispersion of the direct piezoelectric response of BiFeO3 ceramics  

NASA Astrophysics Data System (ADS)

We report on the frequency and stress dependence of the direct piezoelectric d33 coefficient in BiFeO3 ceramics. The measurements reveal considerable piezoelectric nonlinearity, i.e., dependence of d33 on the amplitude of the dynamic stress. The nonlinear response suggests a large irreversible contribution of non-180 domain walls to the piezoelectric response of the ferrite, which, at present measurement conditions, reached a maximum of 38% of the total measured d33. In agreement with this interpretation, both types of non-180 domain walls, characteristic for the rhombohedral BiFeO3, i.e., 71 and 109, were identified in the poled ceramics using transmission electron microscopy. In support to the link between nonlinearity and non-180 domain-wall contribution, we found a correlation between nonlinearity and processes leading to depinning of domain walls from defects, such as quenching from above the Curie temperature and high-temperature sintering. In addition, the nonlinear piezoelectric response of BiFeO3 showed a frequency dependence that is qualitatively different from that measured in other nonlinear ferroelectric ceramics, such as ``soft'' (donor-doped) Pb(Zr,Ti)O3 (PZT), i.e., in the case of the BiFeO3 large nonlinearities were observed only at low field frequencies (<0.1 Hz) possible origins of this dispersion are discussed. Finally, we show that, once released from pinning centers, the domain walls can contribute extensively to the electromechanical response of BiFeO3; in fact, the extrinsic domain-wall contribution is relatively as large as in Pb-based ferroelectric ceramics with morphotropic phase boundary (MPB) composition, such as PZT. This finding might be important in the search of new lead-free MPB compositions based on BiFeO3 as it suggests that such compositions might also exhibit large extrinsic domain-wall contribution to the piezoelectric response.

Rojac, Tadej; Bencan, Andreja; Drazic, Goran; Kosec, Marija; Damjanovic, Dragan

2012-09-01

70

Piezoelectric response of compressive loaded multilayer ceramic actuator  

Microsoft Academic Search

The non-linear piezoelectricity of multilayer ceramic actuators (MCA) using PMNPZT ceramics was investigated under the combined loading of electric field and compressive stress. These piezoelectric actuators present the non-linear ferroelectric behaviors. When electric field and compressive stress are simultaneously applied to the ceramics, the ferroelectricity is expected to be different from that of ceramics induced by only one quantity, electric

Mun-Su Ha; Soon-Jong Jeong; Jung-Hyuk Koh; Hyeong-Bong Choi; Jae-Sung Song

2006-01-01

71

Microstructures of the monomorph piezoelectric ceramic actuators with functional gradients  

Microsoft Academic Search

In this paper, a monolithic ceramic bar with a gradient of piezoelectric activity across its thickness is introduced, which is fabricated by interdiffusion between a high piezoelectric and dielectric compositions. The microstructures of the interdiffusion layer have great effects on the electric field-induced displacement characteristics and interfacial strength of the monomorph piezoelectric actuator. The compositional profiles, phase distributions, and short-range

Xinhua Zhu; Jianmin Zhu; Shunhua Zhou; Qi Li; Zhiguo Liu

1999-01-01

72

Antiwindup controller design for piezoelectric ceramic linear ultrasonic motor drive#  

Microsoft Academic Search

Piezoelectric ceramic ultrasonic motor (USM) is known to be with time-varying and highly nonlinear characteristics. Also it has saturation in the input voltage. In this study, a new antiwindup controller is proposed to control a piezoelectric ceramic linear ultrasonic motor (LUSM) drive system to reduce the influence of nonlinear saturation of the input constraint. First, this study gives theoretical approach

Kuo-Kai Shyu; Cheng-Yuan Chang

2003-01-01

73

Development of highly textured piezoelectric ceramics via templated grain growth  

Microsoft Academic Search

Textured polycrystalline piezoelectric materials are expected to provide improved properties compared to untextured ceramics, and low processing costs compared to single crystals. NexTech Materials is developing textured polycrystalline piezoelectric ceramics via Templated Grain Growth (TGG). In the TGG process, a number of large anisotropic template particles are oriented in a fine particle matrix in the green state, and grow during

M. M. Seabaugh; G. L. Cheney; K. Hasinska; W. J. Dawson; S. L. Swartz

2000-01-01

74

Fabrication of low firing piezoelectric ceramics and their applications  

Microsoft Academic Search

The Low-firing PZT, PNN-PZT, PMN-PNN-PZT systems piezoelectric ceramics with high performance have been studied systematically. By doping suitable additives and optimizing processing, excellent piezoelectric properties could be obtained: Kp=0.50?0.74, d33=(300?705)10C\\/N, ?33 \\/?0 =800?4100, tan?=(40?250)10. The microstructure and the mechanism of transition liquid phase sintering were also investigated. The low firing piezoelectric ceramics have been used for multilayer piezoelectric transformers, ultrasonic

Longtu Li; Zhilun Gui

2001-01-01

75

First-principles study on the electronic and optical properties of Na0.5Bi0.5TiO3 lead-free piezoelectric crystal  

NASA Astrophysics Data System (ADS)

First-principles calculation is used to study the structural, electronic, and optical properties of Na0.5Bi0.5TiO3 (NBT) lead-free piezoelectric crystal. The band structure calculation reveals that NBT has a direct band gap of 2.1 eV. The calculated imaginary part of dielectric function indicates interband transition mainly from O 2p valence bands to Ti 3d and Bi 6p conduction bands in the low-energy region. The calculated absorption spectrum is in agreement with the available experimental data. Based on the fit of the result of optical abruption spectrum, the optical band gap is estimated to be 3.03 eV. Other optical constants, such as refractive index, extinction coefficient, energy-loss spectrum, and reflectivity are discussed in details. Those found show that NBT has the potential applications in optoelectrics.

Zeng, Min; Or, Siu Wing; Chan, Helen Lai Wa

2010-02-01

76

Microscale 1-3-type lead-free piezoelectric/ferrite composites fabricated by a modified dice-and-fill method  

NASA Astrophysics Data System (ADS)

This paper introduces a facile method to fabricate magnetoelectric (ME) composites with microscale lead-free piezoceramic pillars embedded in a ferrite matrix without high-temperature co-sintering. The microscale piezoceramic pillars with a sectional width of about 150 m were obtained from lead-free piezoceramic discs by a dicing method. The spacing between the pillars was backfilled with cobalt ferrite (CFO) nanoparticles, and then a liquid epoxy was infiltrated into the backfilled spacing to bond the filled particles and the pillars. The ME property of the resultant 1-3-type piezoelectric/ferrite composites was verified and found to be significantly dependent on the filling density of the CFO powder, which could be adjusted by repeating the filling step. A maximum ME voltage response of up to 302 V Oe-1 was obtained in a 700 m high composite with pillars of 150 m width and 200 m spacing. The present method provides a potential way to fabricate finescale multiferroic composites for microdevice applications.

Xu, Ying; Li, Jing-Feng; Ma, Jing; Nan, Ce-Wen

2012-08-01

77

Relaxor nature in lead-free Sr5LaTi3Nb7O30 tetragonal tungsten bronze ceramics  

NASA Astrophysics Data System (ADS)

Lead-free tetragonal tungsten bronze Sr5LaTi3Nb7O30 ceramics were prepared and the correlation of the relaxor nature and crystal structure was studied using dielectric spectroscopy and powder X-ray diffraction. Three dielectric relaxations were observed below the deviation temperature TD ~ 330 K. Relaxation I and II followed the Vogel-Fulcher law with the freezing temperatures of 189 K and ~90 K. Low temperature relaxation III, which was first observed in filled tungsten bronze, followed well the Arrhenius law. Dielectric response becomes static below 50 K. Polarization-field (P-E) hysteresis loops were evaluated from 183 K to 298 K. Pr value of 0.41?C/cm2 was observed at 183 K. Deviation of lattice parameter c from the linear contraction and increasing of tetragonality (c/a ratio) were observed below TD, reflecting the structure change during the formation of polar nanoregions and the following freezing process. Opposite tendency was observed below 100 K for all the lattice parameters, corresponding to relaxation III. Generally, the main dielectric relaxation I and II were attributed to flipping and breathing of polar nanoregions along c axis, while the concerted rotations of the oxygen octahedra in the ab plane were suggested as the origin of relaxation III.

Li Zhu, Xiao; Li, Kun; Asif Rafiq, Muhammad; Qiang Liu, Xiao; Ming Chen, Xiang

2013-09-01

78

Microdisplacement characteristics and microstructures of functionally graded piezoelectric ceramic actuator  

Microsoft Academic Search

In this work, we report a functionally gradient piezoelectric ceramic actuator with sandwiched structure prepared by the powder metallurgical method. The functional gradients of piezoelectric activity and dielectric activity vary inversely across the thickness of the actuator. Such functional gradients are obtained by interdiffusion reaction between a high piezoelectric composition [Pb(Zr,Ti)O3\\/PZT] and a high dielectric composition (PbNi1\\/3Nb2\\/3O3\\/PNN). The bending displacement

Xinhua Zhu; Jie Xu; Zhongyan Meng; Jianming Zhu; Shunhua Zhou; Qi Li; Zhiguo Liu; Naiben Ming

2000-01-01

79

Development of novel piezoelectric ceramics and composites for transducer applications  

Microsoft Academic Search

Over the last decade, several methods were utilized to develop novel piezoelectric ceramic\\/polymer composites for transducer applications. Solid freeform fabrication (SFF) is one of the methods that have been emphasized recently. SFF techniques have been used to fabricate polymer, metal or ceramic structures on a fixtureless platform, directly from a computer aided design file. During design verification or the product

Ahmad Safari; Stephen C. Danforth

1998-01-01

80

Piezoelectric ceramics with high dielectric constants for ultrasonic medical transducers  

Microsoft Academic Search

Complex system ceramics Pb(Sc12\\/Nb12\\/)O3-Pb(Mg13\\/Nb23\\/)O3-Pb(Ni12\\/Nb$ d12\\/)O3-(Pb0.965,Sr0.035) (Zr,Ti)O3 (PSN-PMN-PNN-PSZT abbreviated PSMNZT) have been synthesized by the conventional technique, and dielectric and piezoelectric properties of the ceramics have been investigated for ultrasonic medical transducers. High capacitances of the transducers are desired in order to match the electrical impedance between the transducers and the coaxial cable in array probes. Although piezoelectric ceramics that have

Yasuharu Hosono; Yohachi Yamashita

2005-01-01

81

Novel piezoelectric ceramics and composites for sensor and actuator applications  

Microsoft Academic Search

Novel piezoelectric ceramic, and ceramic \\/polymer composite structures were fabricated by solid freeform fabrication (SFF)\\u000a for sensor and actuator applications. SFF techniques including: Fused Deposition of Ceramics (FDC), and Sanders Prototyping\\u000a (SP) were utilized to fabricate a variety of complex structures directly from a computer aided design (CAD) file. Many novel\\u000a and complex composite structures including volume fraction gradients (VFG),

Ahmad Safari

1999-01-01

82

Effects of K/Na ratio on the phase structure and electrical properties of (K{sub x}Na{sub 0.96-x}Li{sub 0.04})(Nb{sub 0.91}Ta{sub 0.05}Sb{sub 0.04})O{sub 3} lead-free ceramics  

SciTech Connect

(K{sub x}Na{sub 0.96-x}Li{sub 0.04})(Nb{sub 0.91}Ta{sub 0.05}Sb{sub 0.04})O{sub 3} (x=0.32-0.56) lead-free piezoelectric ceramics were prepared by conventional sintering. The effects of K/Na ratio on the phase structure and electrical properties of the ceramics were studied. These results indicate that the phase structure undergoes a transition from orthorhombic to tetragonal phase with increase of x. The ceramics with x=0.38 exhibit enhanced electrical properties (d{sub 33}{approx}306 pC/N; k{sub p}{approx}48%; k{sub t}{approx}49%; T{sub c}{approx}337 deg. C; {epsilon}{sub r}{approx}1327; tan {delta}{approx}2.5%; P{sub r}{approx}34.9 {mu}C/cm{sup 2}; E{sub c}{approx}11.3 kV/cm). Enhanced electrical properties of the ceramics should be attributed to the polymorphic phase transition near room temperature. These results show that the ceramic with x=0.38 is a promising lead-free piezoelectric material.

Wu Jiagang; Xiao Dingquan; Wang Yuanyu; Zhu Jianguo; Wu Lang; Jiang Yihang [Department of Materials Science, Sichuan University, Chengdu 610064 (China); Department of Materials Science, Sichuan University, Chengdu 610064 (China) and College of Materials Science and Metallurgy Engineering; Guizhou University, Guizhou 550003 (China); Department of Materials Science, Sichuan University, Chengdu 610064 (China)

2007-12-17

83

Study on the equivalent circuit and coupled vibration for the longitudinally polarized piezoelectric ceramic hollow cylinders  

Microsoft Academic Search

Longitudinally polarized piezoelectric ceramic disks with central holes have been the most commonly used elements in underwater acoustics and ultrasonics. For very thin piezoelectric ceramic disks, its vibration can be regarded as one-dimensional thickness extensional vibration, or plane radial vibration, and the coupling between these two different vibrational modes is neglected. However, for practical piezoelectric ceramic disks with central holes,

Shuyu Lin

2004-01-01

84

Dielectric and piezoelectric properties of 0.95(Na0.5K0.5)NbO3-0.05CaTiO3 ceramics with Ag2O contents  

NASA Astrophysics Data System (ADS)

Lead-Free ceramics 0.95(Na0.5K0.5)NbO3-0.05CaTiO3- x mol. % Ag2O have been fabricated as a function of the amount of Ag2O content. NKN-CT ceramics showed the highest piezoelectric properties and ferroelectric properties at the 0.5 mol. %Ag2O content. The NKN-CT-Ag2O0.5 mol. % ceramics show a good performance with piezoelectric constant d 33 = 221 ?C/N, k p = 0.38%, respectively. The corresponding Curie temperature and remnant polarization reached 370C and 22.5 C/cm2, respectively. These results appear that NKN-CTAg2O ceramics are promising candidate materials for lead-free piezoelectric application.

Lee, Seung-Hwan; Baek, Sang-Don; Kim, Hyun-Ju; Kim, Seung-Hyun; Lee, Sung-Gap; Kim, Dae-Young; Lee, Young-Hie; Nam, Sung-Pill; Lee, Ku-Tak

2012-12-01

85

Effect of Heat Treatment Conditions on Properties of Lead-Free Bi{sub 2}GeO{sub 5} Ferroelectric Glass Ceramics  

SciTech Connect

Nowadays, lead-free ferroelectric materials have attracted much interest among materials scientists as a result of environmental concern. The bismuth germanate (Bi{sub 2}GeO{sub 5}) phase, one of the lead-free ferroelectric crystals, is of particular interest as its composition already contains good glass former (GeO{sub 2}) and can be prepared by an alternative glass ceramic route. In this work, the conventional melt-quenching method was used to produce the parent glass with composition of 60 mol% BiO{sub 1.5}:20 mol% GeO{sub 2}:20 mol% BO{sub 1.5}. The as-received glass pieces were subjected to the heat treatment schedule at various crystallization temperatures and dwell-times. The glass and glass ceramics samples were then investigated by XRD, Raman spectroscopy and their dielectric properties were also measured. The XRD and Raman spectroscopy showed that the crystallinity of the prepared glass ceramics depended very much on crystallization temperature and dwell-time. The larger dielectric constant and lower dielectric loss were obtained as crystallinity of the glass ceramics enhanced. The highest dielectric constant (epsilon{sub r}) was found at 77 with a low dielectric loss of about 0.005.

Kantha, P.; Pengpat, K.; Rujijanagul, G.; Tunkasiri, T.; Eitssayeam, S. [Department of Physics, Faculty of Science, Chiang Mai University, Chiang Mai 50202 (Thailand); Intatha, U. [School of Science, Mae Fha Luang University, Chiang Rai, 57100 (Thailand); Sirisoonthorn, S. [National Metal and Materials Technology Center, Klong Luang, Pathumthani 12120 (Thailand)

2009-07-23

86

Switching characteristics of (Bi1/2Na1/2)TiO3-BaTiO3-(Bi1/2K1/2)TiO3 lead-free ferroelectric ceramics  

NASA Astrophysics Data System (ADS)

The polarization switching characteristics of lead-free a(Bi1/2Na1/2)TiO3-bBaTiO3-c(Bi1/2K1/2)TiO3 (abbreviated as BNBK 100a/100b/100c) ferroelectric ceramics are investigated. This is achieved through examining their polarization and strain hystereses inside and outside the morphotropic phase boundary (MPB). The total induced electrostrain (?33,total) and apparent piezoelectric charge coefficient (d33) first increase dramatically and then decrease gradually as the BNBK composition moves from the tetragonal phase to the MPB and then to the rhombohedral phase. The measured polarization hystereses indicate that the BNBK compositions situated near the rhombohedral side of the MPB typically possess higher coercive field (Ec) and remanent polarization (Pr), while the compositions situated near the tetragonal side of the MPB possess higher apparent permittivity. Adverse effects on the ferroelectric properties are observed when BNBK is doped with donor dopants such as La and Nb. On the contrary, intricate hysteresis behaviors are observed when acceptor dopant Mn is introduced into BNBK. Under an alternating electric field of +/-5.0 MVm-1, BNBK 85.4/2.6/12, a composition well within the MPB, exhibits an ?33,total of ~0.14%, an apparent d33 of 295 pCN-1, an Ec of 2.5 MVm-1 and a Pr of 22.5 ?Ccm-2. These notable ferroelectric property values suggest a candidate material for lead-free actuator applications. The present study provides a systematic set of hysteresis measurements which can be used to characterize the switching behaviors of BNBK-based lead-free ferroelectrics.

Shieh, J.; Wu, K. C.; Chen, C. S.

2007-04-01

87

Large strain response in acceptor- and donor-doped Bi 0.5 Na 0.5 TiO 3 -based lead-free ceramics  

Microsoft Academic Search

Effects of Fe and La addition on the dielectric, ferroelectric, and piezoelectric properties of Bi0.5Na0.5TiO3Bi0.5Li0.5TiO3BaTiO3Mn ceramics were investigated. Similar to the doping effect in lead-based piezoelectric materials, here the Fe-doped ceramic\\u000a created a hard effect with an improved mechanical quality factor (Q\\u000a m)~160, coercive field (E\\u000a c)~2.9kV\\/mm, decreased dielectric constant $$ \\\\left( {\\\\varepsilon_{33}^{T} \\/\\\\varepsilon_{0} } \\\\right)\\\\sim 80 3, $$ and

Tao Wang; Feifei Wang; Chung Ming Leung; Siu Wing; Yanxue Tang; Xinman Chen; Xiaomei Qin; Wangzhou Shi

2011-01-01

88

A Study of Acoustic Emission in Piezoelectric Multilayer Ceramic Actuator  

Microsoft Academic Search

Acoustic emission (AE) in multilayer ceramic actuators (MCA) has been studied. It was observed that AE signals could be concealed by sample's mechanical vibrations under usual MCA driving conditions. These vibrations were caused by an electrical coupling between the sample's piezoelectricity and the power supply's feedback. The AE was observed around the coercive field under bipolar driving. On the contrary,

Hideaki Aburatani; Shoko Yoshikawa; Kenji Uchino; J. W. C. de Vries

1998-01-01

89

Role of Additives on Low Fired High Performance Piezoelectric Ceramics.  

National Technical Information Service (NTIS)

The role of additives on low temperature sintering high performance PMN-PNN-PZT piezoelectric ceramics was studied. ZnO and Li2CO3 can be used as dopants to replace the toxic addition CdCO3. They can reduce the sintering temperature and improve the piezoe...

Z. Gui H. Hu L. Li

1994-01-01

90

Resolution of the ferroelectric domains structure in (K,Na)NbO3-based lead-free ceramics by confocal Raman microscopy  

NASA Astrophysics Data System (ADS)

We highlight some practical aspects in the study of ferroelectric domains in lead-free modified (K,Na)NbO3 piezoceramics through Confocal Raman Microscopy (CRM). In addition, CRM allows the determination of the nature of domain walls and correlation between the structure and piezoelectric properties. The typical configuration of the ferroelectric domain is analyzed in polycrystalline grains of small sizes not exceeding 6 ?m, where tetragonal and orthorhombic domains are coexisting. The accumulated stress produced by the phase coexistence softens the octahedron force constant and reduces the polarization. So, the polarization decrease is associated to the apparition of the orthorhombic phase (O). Finally, we believe that the general strategy and design principles described in this study will open new avenues in developing novel strategies of domains characterization that allow improving the piezoresponse.

Rubio-Marcos, F.; Del Campo, A.; Fernndez, J. F.

2013-05-01

91

Research on micro-displacement driving technology based on piezoelectric ceramic  

NASA Astrophysics Data System (ADS)

Piezoelectric ceramic driving power is one critical technology of achieving the piezoelectric ceramic nano-precision positioning, which has been widely used in precision manufacturing, optical instruments, aerospace and other fields. In this paper, piezoelectric ceramic driving power will be summarized on micro-displacement driving technical development and research. The domestic and overseas piezoelectric-driven ways will be compared and control model algorithms will be discussed. Describe the advantages and disadvantages of piezoelectric ceramic driving power in a different driving and control model, and then show the scope of application of driving power.

Hu, Bo; Tang, Xiaoping; Hu, Song; Yan, Wei; Hu, Zhicheng

2012-10-01

92

Piezoelectric ceramics with high dielectric constants for ultrasonic medical transducers  

Microsoft Academic Search

Complex system ceramics Pb(Sc12\\/Nb12\\/)O3-Pb(Mg13\\/Nb23\\/)O3-Pb(Ni12\\/Nb$ d12\\/)O3-(Pb0.965,Sr0.035)(Zr,Ti)O3 (PSMNZT) have been synthesized by the conventional technique and the dielectric and piezoelectric properties of the ceramics have been investigated for ultrasonic medical transducers. High capacitances of the transducers are desired in order to match the electrical impedance between the transducers and the coaxial cable in array probes with composite transducers. Although high-K ceramics that

Y. Hosono; Y. Yamashita

2004-01-01

93

Morphotropic phase boundary and electrical properties of lead-free (1-x)BaTiO3-xBi(Li1/3Ti2/3)O3 ceramics  

NASA Astrophysics Data System (ADS)

Dense polycrystalline ceramics of lead-free perovskite solid solution (1-x)BaTiO3-xBi(Li1/3Ti2/3)O3 (0.05<=x<=0.20) have been synthesized via the conventional solid state reaction method. A morphotropic phase boundary separating the tetragonal and orthorhombic phases was observed between the compositions x=0.07 and 0.10. With increasing Bi(Li1/3Ti2/3)O3 content, the solid solution displays a stronger frequency dispersion in its dielectric behavior and a significant suppression in the sharp dielectric anomaly at the Curie point as well as the remanent polarization. However, the Curie point of the solid solution is almost independent of x in the composition range studied. These behaviors can be explained by the observed core-shell grain structure. The incorporation of Bi(Li1/3Ti2/3)O3 into BaTiO3 leads to the formation of nanodomains in the shell, which imparts the relaxor characteristics to the dielectric behavior. The core of the grain preserves the large lamellar domains as those in BaTiO3, contributing to the sharp transition at ~130 C. The best piezoelectric coefficient was obtained in the composition x=0.07 with d33=110 pC/N.

Ma, C.; Tan, X.

2010-06-01

94

High-Sensitivity Accelerometer Using Multilayer Piezoelectric Ceramics  

NASA Astrophysics Data System (ADS)

A high sensitivity accelerometer using multilayer piezoelectric ceramics including internal electrodes has been developed. The sensitivity of this accelerometer is about 900 pC/G at the frequency range from 0.01 to 10 Hz. Because the circuit was structed to cancel pyroelectric voltages, the output voltage changes of this accelerometer were decreased to 1/10 compared with the case of a noncanceling circuit.

Ohtsuki, Yasunori; Fuda, Yoshiaki; Yoshida, Tetsuo

1993-09-01

95

Intelligent motion control for linear piezoelectric ceramic motor drive  

Microsoft Academic Search

Since the dynamic characteristics of a linear piezoelectric ceramic motor (LPCM) are highly nonlinear and time varying, it is difficult to design a suitable motor drive and position controller that realizes accurate position control at all time. This study investigates a double-inductance double-capacitance (LLCC) resonant driving circuit and a sliding-mode fuzzy-neural-network control (SMFNNC) system for the motion control of an

Rong-jong Wai; Jeng-dao Lee

2004-01-01

96

Lead-free In{sub 2}O{sub 3}-doped (Bi{sub 0.5}Na{sub 0.5}){sub 0.93}Ba{sub 0.07}TiO{sub 3} ceramics synthesized by direct reaction sintering  

SciTech Connect

Lead-free (Bi{sub 0.5}Na{sub 0.5}){sub 0.93}Ba{sub 0.07}TiO{sub 3}-x wt %In{sub 2}O{sub 3} ceramics synthesized by direct reaction sintering have been studied. X-ray diffraction reveals that all (Bi{sub 0.5}Na{sub 0.5}){sub 0.93}Ba{sub 0.07}TiO{sub 3}-x wt %In{sub 2}O{sub 3} ceramics are of a perovskite structure with coexistence of rhombohedral and tetragonal phases. It is found that the direct reaction sintering promotes growing of ceramic grains while doping of In{sub 2}O{sub 3} contributes to inhibit and homogenize the grain growth, as shown by scanning electron microscopy. The ceramics show excellent piezoelectric and dielectric properties with thickness electromechanical coupling factor k{sub t}=0.503, piezoelectric constant d{sub 33}=205 pC/N, dielectric constant {epsilon}{sub 33}{sup T}/{epsilon}{sub 0}=1046, and loss tangent tan {delta}=0.036.

Zhou Taosheng; Huang Rongxia; Shang Xunzhong; Peng Fei; Guo Jianyong; Chai Liying; Gu Haoshuang; He Yunbin [School of Materials Sciences and Engineering, Hubei University, Wuhan 430062 (China) and Key Laboratory of Ferroelectric and Piezoelectric Materials and Devices of Hubei Province, Hubei University, Wuhan 430062 (China); Department of Physics, Tulane University, New Orleans, Louisiana 70118 (United States)

2007-04-30

97

Piezoelectric properties of Li- and Ta-modified (K{sub 0.5}Na{sub 0.5})NbO{sub 3} ceramics  

SciTech Connect

Lead-free, potassium sodium niobate piezoelectric ceramics substituted with lithium (K{sub 0.5-x/2},Na{sub 0.5-x/2},Li{sub x})NbO{sub 3} or lithium and tantalum (K{sub 0.5-x/2},Na{sub 0.5-x/2},Li{sub x})(Nb{sub 1-y},Ta{sub y})O{sub 3} have been synthesized by traditional solid state sintering. The compositions chosen are among those recently reported to show high piezoelectric properties [Y. Saito, H. Takao, T. Tani, T. Nonoyama, K. Takatori, T. Homma, T. Nagaya, and M. Nakamura, Nature (London) 42, 84 (2004); Y. Guo, K. Kakimoto, and H. Ohsato, Appl. Phys. Lett. 85, 4121 (2004); Mater. Lett. 59, 241 (2005)]. We show that high densities and piezoelectric properties can be obtained for all compositions by pressureless sintering in air, without cold isostatic pressing, and without any sintering aid or special powder treatment. Resonance and converse piezoelectric (strain-field) measurements show a thickness coupling coefficient k{sub t} of 53% and converse piezoelectric coefficient d{sub 33} around 200 pm/V for the Li-substituted ceramics, and a k{sub t} of 52% and d{sub 33} over 300 pm/V for the Li- and Ta-modified samples. The unipolar strain-field hysteresis is small and comparable to that measured under similar conditions in hard Pb(Zr,Ti)O{sub 3}. A peak of piezoelectric properties can be noted close to the morphotropic phase boundary. These ceramics look very promising as possible, practicable, lead-free replacements for lead zirconate titanate.

Hollenstein, Evelyn; Davis, Matthew; Damjanovic, Dragan; Setter, Nava [Ceramics Laboratory, Ecole Polytechnique Federale de Lausanne-EPFL, Lausanne (Switzerland)

2005-10-31

98

Large piezoelectric effect in Pb-free ceramics.  

PubMed

We report a non-Pb piezoelectric ceramic system Ba(Ti(0.8)Zr(0.2))O(3)-(Ba(0.7)Ca(0.3))TiO(3) which shows a surprisingly high piezoelectric coefficient of d(33) approximately 620 pC/N at optimal composition. Its phase diagram shows a morphotropic phase boundary (MPB) starting from a tricritical triple point of a cubic paraelectric phase (C), ferroelectric rhombohedral (R), and tetragonal (T) phases. The high piezoelectricity of the MPB compositions stems from the composition proximity of the MPB to the tricritical triple point, which leads to a nearly vanishing polarization anisotropy and thus facilitates polarization rotation between 001T and 111R states. We predict that the single-crystal form of the MPB composition of the present system may reach a giant d(33) = 1500-2000 pC/N. Our work may provide a new recipe for designing highly piezoelectric materials (both Pb-free and Pb-containing) by searching MPBs starting from a TCP. PMID:20366285

Liu, Wenfeng; Ren, Xiaobing

2009-12-15

99

An investigation of the development of novel piezoelectric actuator designs by fused deposition of ceramics (FDC)  

Microsoft Academic Search

Piezoelectric ceramic materials are widely used in numerous applications for both sensing mechanical force and producing actuation under an applied electric field. In some applications such as manufacturing of optical instruments and semiconductor chips, a displacement of a few hundred microns with a precision positioning of 0.1 mum is required. Piezoelectric ceramics are well suited for such a positioning accuracy,

Farhad Mohammadi

2001-01-01

100

Utilisation of smart polymers and ceramic based piezoelectric materials for scavenging wasted energy  

Microsoft Academic Search

Piezoelectric smart polymer and ceramic materials can be deployed as a mechanism to transform mechanical energy into electrical energy that can be stored and used to power portable devices. This paper focuses on the development and comparison of a micropower based harvesting generator using piezoelectric PZT (lead zirconate titanate) ceramic, PVDF (polyvinylidene fluoride) membrane and PP (polypropylene) foam polymer with

I. Patel; E. Siores; T. Shah

2010-01-01

101

Fabrication of piezoelectric ceramic micro-actuator and its reliability for hard disk drives  

Microsoft Academic Search

A new U-type micro-actuator for precisely positioning a magnetic head in high-density hard disk drives was proposed and developed. The micro-actuator is composed of a U-type stainless steel substrate and two piezoelectric ceramic elements. Using a high-d31 piezoelectric coefficient PMN-PZT ceramic plate and adopting reactive ion etching process fabricate the piezoelectric elements. Reliability against temperature was investigated to ensure the

Yang Jing; Jianbin Luo; Wenyan Yang; Guoxian Ju

2004-01-01

102

Measurement of Micro Vibration of Car by Piezoelectric Ceramics  

NASA Astrophysics Data System (ADS)

Recently, there are various accidents and crimes related to the car. In some cases, the accidents and the crimes can be prevented if it is possible to detect a human who is in the car. For example, we can prevent a baby who is left in a car under the hot weather from dehydration or death occurred by heat inside disease. In another case, it is estimated that the United States currently has as many as 12 million illegal immigrants. In order to prevent further influx of illegal immigrants, the police are physically searching incoming vehicles at national boundaries aiming at finding those who are hiding inside. However, the physical inspections require much manpower cost and time. An inspection method to see inside the vehicles through X-ray images has also been used for this end. But the cost and the installation places are the problems of the large-scale X-ray system. Proposed in this paper is a piezoelectric ceramic system to handily measure the micro vibrations of motor vehicles. And applying the algorithm of Support Vector Machine (SVM), the existence of human body inside vehicles can be detected. The experiment was carried out using four types of vehicles: a mini car; an auto mobile; a van; and a truck weighing 1.5 tons. As the results, the correct determination ratio was 91.2% for the experiment with the piezoelectric ceramic under the front wheels and 97.0% under the rear wheels, when the vehicle used for the examination had also been used together with other three types of vehicles to obtain SVM training data. When the vehicle used for the examination had not been used together with the other three to obtain SVM training data, on the other hand, the correct determination ratio was 93.7% for the experiment with the piezoelectric ceramic under the front wheels and 95.7% under the rear wheels.

Kurihara, Yosuke; Masuyama, Kosuke; Nakamura, Testuo; Bamba, Takeshi; Watanabe, Kajiro

103

Piezoelectric properties of a ferroelectric ceramic  

SciTech Connect

The Michelson interferometer is used for precision measurements of the piezoconstants of a piezoceramic, characterizing the magnitude of the inverse piezoeffect. The authors conclude that the Michelson interferometer has a resolving power of 30 A and ensures an error no greater than 0.05% for the measurement of quasistatic strains, which makes it possible to use the interferometer to study the physiomechanical properties of low-ductility ceramics. Cyclic loading of 3 x 10 x 100 mm specimens of piezoceramics TsTBS-3 at a frequency of about 20 kHz for 60 sec increases the piezoconstant of the material by 8-48% within the range of cyclic-stress amplitudes from 27 to 47 MPa.

Kuz'menko, V.A.; Khavstov, V.K.; Nishchenets, V.N.; Pisarenko, G.G.

1985-08-01

104

Polymorphic phase boundaries and enhanced piezoelectric response in extended composition range in the lead free ferroelectric BaTi1-xZrxO3  

NASA Astrophysics Data System (ADS)

Neutron powder diffraction study of Ba(Ti1-xZrx)O3 at close composition intervals has revealed coexistence of ferroelectric phases: orthorhombic (Amm2) + tetragonal (P4mm) for 0.02 <= x <=0.05 and rhombohedral (R3m) + orthorhombic (Amm2) for 0.07 <= x < 0.09. These compositions exhibit relatively enhanced piezoelectric properties as compared to their single phase counterparts outside this composition region, confirming the polymorphic phase boundary nature of the phase coexistence regions.

Kalyani, Ajay Kumar; Senyshyn, Anatoliy; Ranjan, Rajeev

2013-07-01

105

Raman Spectroscopy Research of Perovskites Lead Free Ferroelectrics  

NASA Astrophysics Data System (ADS)

Recently, lead-free ferroelectrics have been much of interests as an effective alternative to PZT ceramics for the environmental reasons. Notable progress has been made in chemically modified (K0.5Na0.5)NbO3 (KNN) and (Na0.5Bi0.5)TiO3 (NBT)-based lead-free piezoelectric ceramics, which have high piezoelectricity comparable to PZT ceramics. There are many phases and transitions in lead-free ferroelectrics, for instance, ferrolectric, antiferroelectric which are much to be learned from Raman spectroscopy. Some transitions in lead-free ferroelectrics are not sharp but diffuse, or have coexisting phases. Here, there is an introduction to ferroelectricity(FE) and anti-ferroelectricity(AFE). FE is a spontaneous electric polarization of a material that can be reversed by the application of an external electric field or changing temperature. AFE is that materials consist of an ordered array of electric dipoles, but with adjacent dipoles oriented in opposite directions. This can be contrasted with FE, in which the dipoles all point in the same direction. Various spectroscopic techniques have been employed to explore lead-free ferroelectrics, including infrared reflectivity, neutron and x-ray scattering, solid NMR, and Raman scattering, etc. FE type distortions are characterized by unstable or soft phonons, whose frequency decreases on approach transition temperature. Raman is effect for exploring soft mode of FE. For example, for BaTiO3, with temperature change, the body centered Ti atom displaced becoming acentric. Relatively, we can see that when Ti atom moves up while O atoms move down. As a result, dipole moment forms below phase transition. Electron cloud of Ti-O bond changes, with respect to vibration of molecule exhibiting Raman effect. In Raman spectroscopy, a change in molecular polarization potential - or amount of deformation of electron cloud - with respect to vibrational coordinate is required for molecule to exhibit Raman effect. Raman intensity reflects polarizability change and Raman shift stands for proportional to vibrational level involved. Thus from Raman, we can learn much about FE and AFE phase transformations. Raman spectroscopy is effect for researching phase transition in perovskites ferroelectrics.

Luo, L.; Ge, W.; Li, J.; Viehland, D.; Farley, C.; Bodnar, R. J.

2009-12-01

106

Lead-free acoustic emission sensors  

SciTech Connect

Acoustic emission (AE) sensors have been fabricated using both soft- and hard-type lead-free (Na{sub 0.5}K{sub 0.5})NbO{sub 3}-based ceramics. The acoustic and electromechanical properties of the ceramics have been determined using the resonance technique. The lead-free AE sensors were calibrated using a laser source and compared to a commercial sensor. A lead zirconate titanate (PZT) 5H ceramics AE sensor has also been fabricated and calibrated for comparison. It was found that the sensitivity of lead-free AE sensors is comparable to that of the lead-based PZT sensor. To evaluate the sensors for potential application, they have been used in the detection of AE in an impact test. The lead-free sensors can reproduce AE signals accurately without giving artifacts and have potential use in commercial AE systems.

Lam, K. H.; Lin, D. M.; Chan, H. L. W. [Department of Applied Physics, Hong Kong Polytechnic University, Hunghom, Hong Kong, China and Materials Research Centre, Hong Kong Polytechnic University, Hunghom, Hong Kong (China)

2007-11-15

107

Study on the sandwich piezoelectric ceramic ultrasonic transducer in thickness vibration  

NASA Astrophysics Data System (ADS)

A sandwich piezoelectric ceramic ultrasonic transducer in thickness vibration is studied. The transducer consists of front and back metal masses, and coaxially segmented, thickness polarized piezoelectric ceramic thin rings. For this kind of sandwich piezoelectric transducers in thickness vibration, it is required that the lateral dimension of the transducer is sufficiently large compared with its longitudinal dimension so that no lateral displacements in the transducer can occur (laterally clamped). In this paper, the thickness vibration of the piezoelectric ceramic stack consisting of a number of identical piezoelectric ceramic thin rings is analysed and its electro-mechanical equivalent circuit is obtained. The resonance frequency equation for the sandwich piezoelectric ceramic ultrasonic transducer in thickness vibration is derived. Based on the frequency equation, two sandwich piezoelectric ceramic ultrasonic transducers are designed and manufactured, and their resonance frequencies are measured. It is shown that the measured resonance frequencies are in good agreement with the theoretical results. This kind of sandwich piezoelectric ultrasonic transducer is expected to be used in megasonic ultrasonic cleaning and sonochemistry where high power and high frequency ultrasound is needed.

Lin, Shuyu; Tian, Hua

2008-02-01

108

Microstructure Control of Barium Titanate Grain-oriented Ceramics and Their Piezoelectric Properties  

NASA Astrophysics Data System (ADS)

The Barium titanate (BaTiO3, BT) [110] grain-oriented ceramics along [110] direction were prepared by a templated grain growth (TGG) method. The [110] oriented BT platelike particles (t-BT) were used as template particles. The relationship between poling treatment program and piezoelectric constant was investigated. The change in the poling conditions did not greatly influence domain size and the piezoelectric constant. The relationship between piezoelectric properties and domain size in BT grain-oriented ceramics was investigated. The smaller domain size was required to increase the piezoelectric constant.

Mori, Rintaro; Nakashima, Koichi; Fujii, Ichiro; Hayashi, Hiroshi; Nagamori, Yoshitaka; Yamamoto, Yuichi; Wada, Satoshi

2011-10-01

109

Origin of high piezoelectric response in A-site disordered morphotropic phase boundary composition of lead-free piezoelectric 0.93(Na0.5Bi0.5)TiO3-0.07BaTiO3  

NASA Astrophysics Data System (ADS)

Perovskite piezoelectric compositions near the morphotropic phase boundary (MPB) are known to exhibit high piezoelectric response. In lead-based ABO3 compound with B-site disorder, the origin of this enhancement has been associated with the presence of an intermediate monoclinic/orthorhombic state that bridges the adjacent ferroelectric rhombohedral and tetragonal phases. However, the origin of high piezoelectric response in lead-free ABO3 compounds with A-site disorder has not been conclusively established. We describe a microscopic model derived from comparative analyses of high resolution transmission electron microscopy and neutron diffraction that explains the origin of high piezoelectric response in lead-free MPB compositions of 0.93(Na0.5Bi0.5)TiO3-0.07BaTiO3. Direct observation of nanotwins with monoclinic symmetry confirmed the presence of an intermediate bridging phase that facilitates a pathway for polarization reorientation. Monoclinic distortions of an average rhombohedral phase are attributed to localized displacements of atoms along the non-polar directions.

Maurya, Deepam; Murayama, M.; Pramanick, A.; Reynolds, W. T.; An, Ke; Priya, Shashank

2013-03-01

110

Growth and characterization of lead-free piezoelectric BaZr0.2Ti0.8O3Ba0.7Ca0.3TiO3 thin films on Si substrates  

NASA Astrophysics Data System (ADS)

Lead-free piezoelectric BaZr0.2Ti0.8O3Ba0.7Ca0.3TiO3 (BCZT) thin films were grown on La0.7Sr0.3MnO3-buffered Si (0 0 1) by off-axis RF magnetron sputtering at temperatures ranging from 550 to 810 C. In this article, we present the detailed investigation on structure, leakage current behaviors and electromechanical properties of BCZT thin films. The crystallographic texture and grain size of the as-grown thin films are strongly dependent on the growth temperature, which consequently affects the leakage behaviors and local electromechanical properties. The crystallographic orientation becomes better and the grain size increases when increased the substrate temperature. The dominant leakage mechanism is found to be space-charge-limited conduction at low electric field, while a Fowler-Nordheim tunneling is confirmed in high electric field region for the films deposited at 710 C and 810 C. The increasing growth temperature also leads to remarkable improvement in the local electromechanical properties of the films. The BCZT film deposited at an optimal temperature of 810 C exhibits a considerably high effective piezoelectric coefficient d33,f of 94 4 pm/V, which is comparable to that of a typical lead zirconate titanate thin film.

Luo, B. C.; Wang, D. Y.; Duan, M. M.; Li, S.

2013-04-01

111

EFFECT OF BiFeO3 DOPING ON FERROELECTRIC AND PIEZOELECTRIC PROPERTIES OF (Bi0.5Na0.5)TiO3 AND BaTiO3 CERAMICS  

Microsoft Academic Search

The effects of BiFeO3 (BF) doping on the phase transition temperatures especially of lead-free piezoelectric materials were studied. Up to 20 mole% of BFO was doped in (Bi0.5Na0.5)TiO3 (BNT) and BaTiO3 (BT) ceramics synthesized by solid state reactions. In BNT, ferroelectric transition temperature (TC) increased with doping but depolarization temperature (Td) was almost independent of BF contents. In BT, however,

K. H. RYU; T. K. SONG; M.-H. KIM; S. H. LEE; Y. S. SEONG; S. J. JEONG; J. S. SONG

2006-01-01

112

Piezoelectric and Dielectric Properties of Calcium and Samarium Modified Lead Titanate Ceramics for Hydroacoustic Applications.  

National Technical Information Service (NTIS)

Piezoelectric lead titanate ceramics are promising materials for applications in underwater acoustics as well as ultrasound technology. These materials are highly anisotropic and possess high sensitivity to hydroacoustic signals applied under hydrostatic ...

K. M. Rittenmyer R. Y. Ting

1990-01-01

113

Behavior of soft piezoelectric ceramics under high sinusoidal electric fields  

NASA Astrophysics Data System (ADS)

The behavior of piezoelectric, dielectric, and elastic characteristics of soft piezoelectric lead zirconate titanate (PZT) ceramics was investigated under sinusoidal electric field E applied along the poling direction and under mechanical stress-free conditions for a frequency range 10 Hz-10 kHz. Electrical displacement D3 along the poling direction, mechanical strain S1 in the direction perpendicular to the poling direction, and the resonant frequency ?r of electromechanically uncoupled bending vibrations of polarized plates were measured. Commercial ceramics PZT5H, 3203HD, and PKI550 with chemical composition near the morphotropic phase boundary were used in the study. It was found that the amplitude and phase of the first harmonic of the relative strain S1(1)/Em and of the relative electrical displacement D3(1)/Em increase similarly with increasing amplitude Em of the electric field if the amplitude is less than coercive field. The corresponding increase in the square of the resonant frequency is more moderate. The dependencies are described well by linear functions except for low electric fields. The functions S1m(1)/Em and D3m(1)/Em demonstrate frequency dispersion as well. Relative amplitude of the second harmonic of the electrical displacement, D3m(2)/D3m(1), which is polar, also increases almost linearly with increasing Em. The relative third harmonic D3m(3)/D3m(1) demonstrates saturationlike behavior. By means of the electric pulse technique, it was found that irreversible changes in the remnant polarization take place even at electric fields much smaller that the coercive field. A mathematical model of a hysteretic transducer, describing the electric field dependence of electromechanical properties of soft piezoelectric PZT ceramics, was suggested. According to this approach, the response depends not only on the instantaneous magnitude of the input signal (e.g., electric field) but also on its past extreme values. It was shown that the experimental Rayleigh law is a particular case of the suggested approach. The model relates directly electric field dependencies of complex piezoelectric coefficient d31(Em) and S1(1)/Em, of complex dielectric permittivity ?33T(Em) and D3(1)/Em, and of the amplitude of elastic compliance s11E(Em) and ?r2. Application of the model to experimental data showed that the model describes well the first three complex harmonics of D3 and the irreversible change in the remnant polarization. Physical causes of the observed behavior were analyzed. As an alternative to the model based on the 90 polarization reorientation and tetragonal/rhombohedral phase boundary motion, a new approach was suggested. In this model, the observed hysteretic changes in the electromechanical properties are assumed to be caused by the electric field dependency of the mechanical stress acting at interdomain boundaries in the partly constrained crystallites of these ceramics.

Kugel, V. D.; Cross, L. E.

1998-09-01

114

Third order longitudinal mode piezoelectric ceramic transformer and its application to high-voltage power inverter  

Microsoft Academic Search

Color liquid crystal displays (LCD) require low-profile, miniaturized and highly efficient power inverters, replacing conventional electromagnetic transformers, to light up their backlights, which include cold cathode fluorescent lamps (CCFL). The object of this study is to actualize the power inverter, to which a novel multilayered piezoelectric ceramic transformer operating in the third order longitudinal mode is applied. The piezoelectric transformer

S. Kawashima; O. Ohnishi; H. Hakamata; S. Tagami; A. Fukuoka; T. Inoue; S. Hirose

1994-01-01

115

A novel approach to electrochromism in WO3 thin film using piezoelectric ceramics for power supply  

Microsoft Academic Search

Electrochromism was newly realized in a WO3Pb(Zr0.52Ti0.48)O3 (PZT) system which utilized the piezoelectric property of PZT ceramics for power supply. The electric power produced by Mn-doped PZT ceramics enabled the WO3 film to color blue. High piezoelectricity with a peak voltage of 35 V and peak current of 1.2 mA on a 30 k? circuit was observed at a pressure

C. N. Xu; M. Akiyama; P. Sun; T. Watanabe

1997-01-01

116

Electrical properties and sensing ability of novel piezoelectric ceramic fibers with Pt core  

NASA Astrophysics Data System (ADS)

The traditional sintering method was used to sinter the pure and Fe2O3 doped 0.55Pb(Ni0.33Nb0.67)O3-0.45Pb(Zr0.3Ti0.7)O3 (abbreviate as PNN-PZT and PFNN-PZT, respectively) ceramics. The addition of Fe2O3 significantly improved the microstructure and electrical properties. Compared with pure PNN-PZT ceramics, higher dielectric and piezoelectric properties of d31~-390 pC/N, ? r ~6298 were obtained for the PFNN-PZT sample sintered at 1175C for 2 h. Hence, the PFNN-PZT ceramics sample was selected to fabricate piezoelectric ceramic fibers with Pt core (PFC). Both the green fibers and bulk ceramics were sintered at 1150-1225C for 2 h in a closed crucible, respectively. The effect of sintering temperature on the microstructure and electrical properties of the PFNN-PZT fibers was investigated. The optimal piezoelectric properties are obtained for the sample sintered at 1175C for 2 h. The relative dielectric constant and piezoelectric constant show peak values of ? r~3683, d31~-197.4 pC/N, respectively. The PFC is a new type piezoelectric device, which can be used for sensors or actuators. The results of sensing experiment show that the piezoelectric ceramic fiber with Pt core has high sensitivity for the Lamb waves.

Du, Jianzhou; Qiu, Jinhao; Zhu, Kongjun; Ji, Hongli; Zhao, Huayun

2012-03-01

117

Electrical Characteristics of Ultrasonic Nozzle Using Multilayer Ring-Type Piezoelectric Ceramics for Light Oil Spray  

Microsoft Academic Search

In this paper, ultrasonic nozzle and its driving circuit were manufactured. And then, their electrical properties were investigated. Ultrasonic nozzle using multilayer ring-type piezoelectric ceramics was fabricated by Pb[(Mn1\\/3Nb2\\/3)0.02(Ni1\\/3Nb2\\/3)0.12(Zr0.50Ti0.50)0.86]O3 (abbreviated as PMN-PNN-PZT) composition which have excellent piezoelectric characteristics. The multilayer ring-type piezoelectric ceramics using pure Ag inner electrode was sintered at 900C low temperatures. In order to drive ultrasonic nozzle,

Jinhee Kang; Yuhyong Lee; Larkhoon Hwang; Juhyun Yoo; Jaeil Hong

2010-01-01

118

Influence of phase composition on electrostrains of doped (Bi0.5Na0.5)TiO3-BaTiO3-(Bi0.5K0.5)TiO3 lead-free ferroelectric ceramics  

NASA Astrophysics Data System (ADS)

The actuating properties such as the electrostrain and piezoelectric charge coefficient d33 of the lead-free 0.854(Bi0.5Na0.5)TiO3-0.026BaTiO3-0.12(Bi0.5K0.5)TiO3 (abbreviated as BNBK 85.4/2.6/12) ferroelectric ceramic upon manganese (Mn) or cobalt (Co) doping are investigated. These dopants are chosen to improve the sinterability and ferroelectric characteristics of BNBK 85.4/2.6/12. Intricate straining behaviors are observed upon Mn dopingan electrostrain of about 0.1% can be maintained when the Mn doping amount is in between 0.5 and 1.5 mol%. Once outside this doping range, the induced electrostrain is considerably smaller. In contrast, for the Co-doped BNBK 85.4/2.6/12 ceramics, the values of electrostrain and d33 stay relatively constant regardless of the Co doping level. By examining the evolution of crystalline phase composition with increasing doping concentration, the mole content of the rhombohedral phase is shown to be a critical factor in deciding the straining behaviors of the doped BNBK 85.4/2.6/12 ceramics. At each increasing step in Mn or Co doping level, there is a marked similarity in the evolution of the induced electrostrain and rhombohedral phase content.

Shieh, J.; Lin, Y. C.; Chen, C. S.

2010-09-01

119

Effects of one-dimensional compressive stress on the properties of multilayer piezoelectric ceramic actuator  

Microsoft Academic Search

The mechanical characteristics of the multilayer piezoelectric ceramic actuator (MPCA) are discussed, especially the relation between one-dimensional stress and strain. The samples were rectangular solids made of PZT system ceramics. The polarized samples to which the constant electric field was applied were loaded with one-dimensional stress by a universal testing machine and the displacement was measured. The samples to which

M. Kondo; K. Ohya; S. Shimizu

1990-01-01

120

Design and characterization of a carbon-nanotube-reinforced adhesive coating for piezoelectric ceramic discs  

Microsoft Academic Search

The silver paste electrode of piezoelectric (PZT) ceramic discs has been shown to produce a weak interface bond between a bare PZT and its paste coating under a peeling force. In this work, an investigation was conducted to reinforce the bond with a high density array of oriented carbon nanotube nano-electrodes (CNTs-NEA), between a bare PZT ceramic and a metal

G. Lanzara; F.-K. Chang

2009-01-01

121

Piezoelectric Properties of V and Ba Substituted SrBi2Nb2O9 Ceramics  

Microsoft Academic Search

Piezoelectric properties of vanadium and barium-substituted strontium bismuth niobate, Sr1?xBaxBi2Nb2?yVyO9 [SBBNV-x (x = 0.0?0.2, y = 0.05)] ceramics synthesized by a low-temperature ceramic fabrication process were investigated. Grain orientation effects on their piezoelectric properties were also investigated using a hot-forging (HF) method. SBBNV-x ceramics were sintered at 950?1050C. This sintering temperature is about 200C lower than that of non-V-substituted SBBN-x.

Shinya Inai; Jyunpei Sato; Rintaro Aoyagi; Yuji Hiruma; Muneyasu Suzuki; Hajime Nagata; Tadashi Takenaka

2007-01-01

122

Cement-based piezoelectric ceramic composites for sensor applications in civil engineering  

NASA Astrophysics Data System (ADS)

The objectives of this thesis are to develop and apply a new smart composite for the sensing and actuation application of civil engineering. Piezoelectric ceramic powder is incorporated into cement-based composite to achieve the sensing and actuation capability. The research investigates microstructure, polarization and aging, material properties and performance of cement-based piezoelectric ceramic composites both theoretically and experimentally. A hydrogen bonding is found at the interface of piezoelectric ceramic powder and cement phase by IR (Infrared Ray), XPS (X-ray Photoelectron Spectroscopy) and SIMS (Secondary Ion Mass Spectroscopy). It largely affects the material properties of composites. A simple first order model is introduced to explain the poling mechanism of composites and the dependency of polarization is discussed using electromechanical coupling coefficient kt. The mechanisms acting on the aging effect is explored in detail. Dielectrical, piezoelectric and mechanical properties of the cement-based piezoelectric ceramic composites are studied by experiment and theoretical calculation based on modified cube model (n=1) with chemical bonding . A complex circuit model is proposed to explain the unique feature of impedance spectra and the instinct of high-loss of cement-based piezoelectric ceramic composite. The sensing ability of cement-based piezoelectric ceramic composite has been evaluated by using step wave, sine wave, and random wave. It shows that the output of the composite can reflects the nature and characteristics of mechanical input. The work in this thesis opens a new direction for the current actuation/sensing technology in civil engineering. The materials and techniques, developed in this work, have a great potential in application of health monitoring of buildings and infrastructures.

Dong, Biqin

123

Complete set of material constants of 0.95(Na0.5Bi0.5)TiO3-0.05BaTiO3 lead-free piezoelectric single crystal and the delineation of extrinsic contributions  

NASA Astrophysics Data System (ADS)

Lead-free piezoelectric single crystal 0.95(Na0.5Bi0.5)TiO3 (NBT)-0.05BaTiO3 was grown by top-seeded solution growth method, which has rhombohedral symmetry with composition near morphotropic phase boundary. Full set of dielectric, piezoelectric, and elastic constants for [001]c poled domain-engineered single crystal was determined. Excellent electromechanical properties and low dielectric loss (d33 = 360 pC/N, d31 = -113 pC/N, d15 = 162 pC/N, k33 = 0.720, kt = 0.540, and tan ? = 1.1%) make it a good candidate to replace lead-based piezoelectric materials. The depolarization temperature (Td = 135 C) is the highest among all NBT-based materials and its electromechanical coupling properties are very stable below Td. Extrinsic contributions to piezoelectric properties were investigated by Rayleigh analysis.

Zheng, Limei; Yi, Xiujie; Zhang, Shantao; Jiang, Wenhua; Yang, Bin; Zhang, Rui; Cao, Wenwu

2013-09-01

124

Temperature dependences of piezoelectric properties of vanadium substituted SrBi 2Nb 2O 9 ceramics with grain orientation  

Microsoft Academic Search

The temperature dependence of the piezoelectric properties of vanadium substituted strontium bismuth niobate, SrBi2Nb1.95V0.05O9 (SBNV) ceramics, were investigated in various vibration modes. The effects of grain orientation in SBNV ceramics on the piezoelectric properties were also studied by the hot-forging (HF) method. The anisotropy of the piezoelectric properties of each vibration mode was confirmed by observing the grain orientation. In

Shinya Inai; Yuji Hiruma; Muneyasu Suzuki; Hajime Nagata; Tadashi Takenaka

2008-01-01

125

Effect of silver dopant on electrical properties of PMNPNNPZT piezoelectric ceramics by complex impedance spectroscopy  

Microsoft Academic Search

Silver migration has been extensively identified during the preparation of multilayer piezoelectric transformers with silverpalladium inner electrodes. This paper reported on the AC impedance characteristic of silver-doped PMNPNNPZT piezoelectric ceramics. The experimental results showed that a small amount of silver addition changed the electrically conductive process of PMNPNNPZT piezoelectric ceramics from nearly complete grain conductivity to grain and grain boundary

Ruzhong Zuo; Longtu Li; Xiaobing Hu; Zhilun Gui

2002-01-01

126

Realization of high-energy density polycrystalline piezoelectric ceramics  

Microsoft Academic Search

This letter reports a high energy density piezoelectric material in the system given as: Pb[(Zr0.52Ti0.48)O3]1-x[(Zn1\\/3Nb2\\/3)O3]x+yMnCO3, where x=0.1 and y varies from 0.5 to 0.9 wt %. A piezoelectric material with high energy density is characterized by a high product of piezoelectric voltage constant (g) and piezoelectric strain constant (d). The condition for obtaining large magnitude of g constant was derived

Rashed Adnan Islam; Shashank Priya

2006-01-01

127

Direct measurement of the domain switching contribution to the dynamic piezoelectric response in ferroelectric ceramics  

NASA Astrophysics Data System (ADS)

The dynamic piezoelectric response of ferroelectric ceramics is comprised of both intrinsic (piezoelectric lattice strain) and extrinsic (non-180 domain wall motion) components. Here the authors report direct measurements of non-180 domain wall motion in ceramic lead zirconate titanate during application of subcoercive cyclic driving electric fields using an in situ stroboscopic neutron diffraction technique. During unipolar cycling at 1 Hz and half of the coercive field, non-180 domain switching gives rise to approximately 34% of the measured d33 coefficient of 400 pm/V.

Jones, Jacob L.; Hoffman, Mark; Daniels, John E.; Studer, Andrew J.

2006-08-01

128

Piezoelectric properties of x/65/35 PLZT ceramics depended of the lanthanum (x) ions contents  

NASA Astrophysics Data System (ADS)

For many years the PLZT ceramics have been known as a ferroelectric material which has various electro-optic and piezoelectric properties. The aim of this work was to study how the lanthanum dopant (x) influences on the piezoelectric properties of x/65/35 PLZT ceramics. All samples were sintered by the hot uniaxial pressing method, from the sol-gel derived powders. The measurements enclose the complex of electric parameters, such as: \\varepsilon , tg? , k{p}, k31, d31, SE11, g31, VR. The domain structures of unpoled and poled samples were conducted on the FESEM HITACHI S-4700.

P?o?ska, M.; Surowiak, Z.

2006-11-01

129

Temperature behavior of dielectric and piezoelectric properties of samarium-doped lead titanate ceramics  

Microsoft Academic Search

The dielectric and electromechanical coupling properties of Sm-doped and Mn-doped PbTiO3 ceramics were investigated from 4.2 to 300 K. The upper and lower limits of the ceramic dielectric and piezoelectric properties were calculated by averaging the single-domain constants that were determined from a phenomenological theory. Comparisons of the measured and calculated properties were then made. The measured dielectric permittivity ?T33

J. N. Kim; MICHAEL J. HAUN; SEI JOO JANG; L. E. Cross; X. R. Xue

1989-01-01

130

Gamma Ray Irradiation Effects on the Ferroelectric and Piezoelectric Properties of Barium Titanate Ceramics  

NASA Astrophysics Data System (ADS)

The effect of heavy dose gamma ray irradiation on the ferroelectric and piezoelectric properties of barium titanate (BaTiO3) ceramics has been investigated. It is found that on irradiation the ferroelectric property decreases and polarization behavior shows double loop hysteresis. The piezoelectric properties including piezoelectric charge constant ( d 33), electromechanical coupling coefficient ( K p), and electrostrictive strain also decreases. The most probable reason for decreased ferroelectric and piezoelectric properties may be the occurrence of random local strain upon irradiation. The phase transition temperature from ferroelectric to paraelectric decreases and degree of diffuseness increases on irradiation. The thermoluminescence (TL) glow curve showed a peak at 226 C showing that irradiated BaTiO3 has TL properties. Presence of TL clearly indicates that gamma ray irradiation causes trapped holes and electrons and these trapped charges are released at temperature higher than 226 C. The creation of trapped holes and electrons effected the microstrain of BaTiO3 ceramic leading to change in the ferroelectric and piezoelectric properties of BaTiO3 ceramic.

Medhi, Nirmali; Nath, A. K.

2013-09-01

131

Recurrent fuzzy neural network control for piezoelectric ceramic linear ultrasonic motor drive  

Microsoft Academic Search

In this study, a recurrent fuzzy neural network (RFNN) controller is proposed to control a piezoelectric ceramic linear ultrasonic motor (LUSM) drive system to track periodic reference trajectories with robust control performance. First, the structure and operating principle of the LUSM are described in detail. Second, because the dynamic characteristics of the LUSM are nonlinear and the precise dynamic model

Faa-Jeng Lin; Rong-Jong Wai; Kuo-Kai Shyu; Tsih-Ming Liu

2001-01-01

132

A VME Board Prototype of High Voltage Power Supply Incorporating Piezoelectric Ceramic Transformer  

Microsoft Academic Search

A high voltage power supply channel produces a stabilized direct current high voltage, utilizing a piezoelectric ceramic transformer to generate high voltage. With the intention of developing a 16-channel VME board, a single channel VME board was prototyped, where a high voltage power supply was implemented on a VME board so that a computer could control the power supply. The

Masatosi Imori; Takashi Taniguchi; Toshiyuki Kimura; Satoru Imada

133

Supervisory control for linear piezoelectric ceramic motor drive using genetic algorithm  

Microsoft Academic Search

This paper presents a supervisory genetic algorithm (SGA) control system for a linear piezoelectric ceramic motor (LPCM) driven by a two-inductance two-capacitance resonant driving circuit. First, the motor configuration and driving circuit of an LPCM are introduced, and its hypothetical dynamic model is described briefly. Since the dynamic characteristics and motor parameters of the LPCM are highly nonlinear and time

Rong-Jong Wai; Kuo-Ho Su

2006-01-01

134

Transducer Performance for Leaky Wave in Layered Structure of Piezoelectric Ceramic Thin Plate and Acryl Plate  

Microsoft Academic Search

A leaky wave transducer in the combination of a piezoelectric ceramic thin plate and an acryl plate is described, which functions as a transducer for underwater ultrasound. The operation performance of an interdigital transducer in the layered structure is described from the viewpoint of phase velocity, electromechanical coupling constant, mode conversion efficiency and transducer efficiency. The leaky wave transducer has

Kohji Toda; Yasuhiko Akutsu

1994-01-01

135

Electro-elastic properties of porous piezoelectric ceramics obtained by tape casting  

Microsoft Academic Search

The electro-elastic properties of porous piezoelectric ceramics obtained by tape casting have been investigated and related with sample microstructure. The samples obtained by tape casting show very narrow pore size distribution for all porosities up to 60%. Reproducible properties and regular dependence of electro-elastic constants on porosity are consequently obtained. It was found that some material properties are improved with

F. Craciun; C. Galassi; E. Roncari; A. Filippi; G. Guidarelli

1998-01-01

136

Operational principle, fabrication and displacement characteristics of a functionally gradient piezoelectric ceramic actuator  

Microsoft Academic Search

In this paper, the theoretical relationship between the bending displacement at the free end of a functionally gradient material (FGM) actuator and the FGM coefficient of the sandwich has been derived from the structure of an FGM actuator. FGM actuators based on PNN-PZT piezoelectric ceramics have been developed by the powder mould stacking press method and their displacement characteristics have

Xinhua Zhu; Zhongyan Meng

1995-01-01

137

Bending strength of piezoelectric ceramics and single crystals for multifunctional load-bearing applications.  

PubMed

The topic of multifunctional material systems using active or smart materials has recently gained attention in the research community. Multifunctional piezoelectric systems present the ability to combine multiple functions into a single active piezoelectric element, namely, combining sensing, actuation, or energy conversion ability with load-bearing capacity. Quantification of the bending strength of various piezoelectric materials is, therefore, critical in the development of load-bearing piezoelectric systems. Three-point bend tests are carried out on a variety of piezoelectric ceramics including soft monolithic piezoceramics (PZT-5A and PZT-5H), hard monolithic ceramics (PZT-4 and PZT-8), single-crystal piezoelectrics (PMN-PT and PMN-PZT), and commercially packaged composite devices (which contain active PZT-5A layers). A common 3-point bend test procedure is used throughout the experimental tests. The bending strengths of these materials are found using Euler-Bernoulli beam theory to be 44.9 MPa for PMN-PZT, 60.6 MPa for PMN-PT, 114.8 MPa for PZT- 5H, 123.2 MPa for PZT-4, 127.5 MPa for PZT-8, 140.4 MPa for PZT-5A, and 186.6 MPa for the commercial composite. The high strength of the commercial configuration is a result of the composite structure that allows for shear stresses on the surfaces of the piezoelectric layers, whereas the low strength of the single-crystal materials is due to their unique crystal structure, which allows for rapid propagation of cracks initiating at flaw sites. The experimental bending strength results reported, which are linear estimates without nonlinear ferroelastic considerations, are intended for use in the design of multifunctional piezoelectric systems in which the active device is subjected to bending loads. PMID:22711404

Anton, Steven R; Erturk, Alper; Inman, Daniel

2012-06-01

138

Effect of gamma ray irradiation on the ferroelectric and piezoelectric properties of barium stannate titanate ceramics  

NASA Astrophysics Data System (ADS)

Tin doped barium titanate ceramics has been obtained by solid state reaction method followed by high energy ball milling. The effect of heavy dose gamma ray irradiation on the ferroelectric and piezoelectric properties of the synthesized barium stannate titanate ceramics has been observed. It has been found that on irradiation the ferroelectric property decreases with decreasing values of Pr and Ec. The piezoelectric properties including d33, electrostrictive strain and electromechanical coupling coefficient (Kp) also decrease following the same trend of Pr and Ec. Grain size decreases and grain patterns become irregular after irradiation as observed from SEM micrographs. The Thermoluminescence (TL) property of the barium stannate titanate ceramics has also been investigated and reported.

Nath, A. K.; Medhi, Nirmali

2013-10-01

139

High temperature lead-free relaxor ferroelectric: Intergrowth Aurivillius phase BaBi{sub 2}Nb{sub 2}O{sub 9}-Bi{sub 4}Ti{sub 3}O{sub 12} ceramics  

SciTech Connect

Intergrowth BaBi{sub 2}Nb{sub 2}O{sub 9}-Bi{sub 4}Ti{sub 3}O{sub 12} (BaBi{sub 6}Ti{sub 3}Nb{sub 2}O{sub 21}) Aurivillius phase ceramic has been found to be a relaxor ferroelectric (RFE) with the highest reported temperature of the maximum of the dielectric permittivity (T{sub m}) of all of the known RFE systems. Dielectric characterization revealed that it has two dielectric anomalies. The first one is a frequency independent broad dielectric constant peak at {approx}280 deg. C, while the second anomaly shows relaxor behavior at 636 deg. C (100 kHz). There is obvious frequency dispersion of dielectric response at room temperature, which is in agreement with dielectric properties of a typical relaxor. Ferroelectric hysteresis loops and a measurable value of piezoelectric constant d{sub 33} confirmed the ferroelectric nature of BaBi{sub 6}Ti{sub 3}Nb{sub 2}O{sub 21} ceramics. The piezoelectric response remained even after annealing at temperatures above 636 deg. C.

Zhang Hongtao [School of Engineering and Materials Science, Queen Mary University of London, London E1 4NS (United Kingdom); Department of Materials, University of Oxford, Oxford OX1 3PH (United Kingdom); Yan Haixue; Reece, Michael J. [School of Engineering and Materials Science, Queen Mary University of London, London E1 4NS (United Kingdom); Nanoforce Technology Ltd., London E1 4NS (United Kingdom)

2010-05-15

140

Annealing effects on the characteristics of high Tc lead-free barium titanate-based positive temperature coefficient of resistivity ceramics  

NASA Astrophysics Data System (ADS)

Annealing effects on the positive temperature coefficient of resistivity (PTCR) behavior of (Bi1/2Na1/2)TiO3 and (Bi1/2K1/2)TiO3 modified BaTiO3 semiconducting ceramics are investigated. The annealing treatments result in the occurrence of the PTCR effect and the increased resistivity jump. The impedance spectra reveal that the resistivity of grain interior of annealed sample is little influenced by the annealing process, indicating that the increase in the overall resistivity is entirely a grain-boundary effect. A higher annealing temperature leads to an increase in acceptor state density, potential barrier height and barrier layer width, which contributes to the improved PTCR effect in the annealed samples.

Xiang, Ping-Hua; Harinaka, Hisashi; Takeda, Hiroaki; Nishida, Takashi; Uchiyama, Kiyoshi; Shiosaki, Tadashi

2008-11-01

141

Study on piezoelectric ceramic\\/metal composite thin plate of driving stator for travelling-wave motor  

Microsoft Academic Search

In this paper the solution of general problems of the bending vibration of the thin piezoelectric ceramic\\/metal composite plate of a driving stator for a travelling-wave motor was analysed. Considering the electromechanical coupling effect, the concepts of generalized stress and strain and generalized piezoelectric equations were introduced. The relation of generalized stress and strain, satisfying the differential motion equation of

Shuxiang Dong; Longtu Li; Xiaowen Zhang

1994-01-01

142

Low temperature sintering of lead magnesium nickel niobate zirconate titanate (PMN-PNN-PZT) piezoelectric ceramic, with high performances  

Microsoft Academic Search

Low temperature sintering of quarternary system lead magnesium nickel niobate zirconate titanate (PMN-PNN-PZT) piezoelectric ceramics has been investigated. This ceramic with proper additives could be sintered at about 900C and exhibited excellent piezoelectric properties: Kp = 0.610.65, Qm ? 1000, ?T\\/33\\/?0 = 23002800, d33 = 430465 10 C\\/N, tg? ? 50 10, ? = 7.98.01 g\\/cm. The microstructure

Gui Zhilun; Li Longtu; Lin Hongqing; Zhang Xiaowen

1990-01-01

143

Low temperature sintering and high piezoelectric properties of strontium doped PNZTPNN ceramics processed via the columbite route  

Microsoft Academic Search

This study investigated the influence of strontium doping on both the sintering behavior and the piezoelectric properties of PNZTPNN ceramics. The piezoelectric ceramics was produced by solid state reaction between metallic oxides, strontium carbonates (SrCO3) and oxides precursors. NiNb2O6 precursors were mixed with the oxides to avoid the large-scale formation of pyrochlore phases during the sintering process and to favor

Franois Bamire; Katrin Benkert; Morgane Radanielina; Carsten Schuh; Michael J. Hoffmann

2007-01-01

144

Modified cofiring behaviors between PMN-PNN-PZT piezoelectric ceramics and PZT-doped 70Ag30Pd alloy metallization  

Microsoft Academic Search

The cofiring behaviors between PMN-PNN-PZT piezoelectric ceramics and 70Ag30Pd electrode paste were investigated in view of sintering densification behavior, thermal expansion coefficients (TEC) and interfacial physical integrity. The results showed that mismatched cofiring characteristics have greatly affected the reliability of multilayer piezoelectric ceramic devices. The application of a PZT additive to 70Ag30Pd electrode technology has markedly improved the above-mentioned cofiring

Ruzhong Zuo; Longtu Li; Zhilun Gui

2002-01-01

145

Electrostrictive and relaxor ferroelectric behavior in BiAlO3-modified BaTiO3 lead-free ceramics  

NASA Astrophysics Data System (ADS)

The crystal structure of (1-x)BaTiO3-xBiAlO3 (x = 0, 0.02, 0.05, 0.08, and 0.1) ceramics was determined using X-ray diffraction and Raman spectroscopy at room temperature, which revealed a phase transition from tetragonal to rhombohedral with increasing x. The dielectric properties were studied as a function of temperature at different frequencies, which indicated that the phase transition temperature (Tm) decreased with increasing x. The relaxor behavior was observed by frequency and temperature dependent dielectric permittivity. The Lorenz-type quadratic law was used to characterize the dielectric permittivity peaks near Tm of high-temperature slopes at 1 MHz. The temperatures Tm of dielectric permittivity peaks fit very well with the Vogel-Fulcher law in x = 0.05 and x = 0.1. The polarization hysteresis loops and electrostrictive were displayed at room temperature. The sample for x = 0.1 exhibits a slim loop with negligible hysteresis and a subtle linear feature, which is a promising transducer material for use as an active element.

Zheng, Shaoying; Odendo, Erika; Liu, Laijun; Shi, Danping; Huang, Yanming; Fan, Longlong; Chen, Jun; Fang, Liang; Elouadi, Brahim

2013-03-01

146

Effect of lanthanum doping on the structural, ferroelectric, and strain properties of Bi1/2(Na0.82K0.18)1/2TiO3 lead-free ceramics  

NASA Astrophysics Data System (ADS)

To clarify the effect of A-site donor doping on the phase transition and the strain enhancement, we investigated the crystal structure, as well as the piezoelectric, ferroelectric and electric-field-induced strain (EFIS) properties of La-doped Bi1/2(Na0.82K0.18)1/2TiO3 (BNKT) ceramics. Similarly to our previous studies on BNKT doped with B-site donors such as Nb and Ta, La doping was found to induce a ferroelectric-to-nonpolar (FE-NP) phase transition, leading to a large enhancement in EFIS just after the transition. The result provides strong evidence that a close relationship exists between the Goldschumidt's tolerance factor and the FE-NP transition in BNKT, which has been observed in B-site-donor or isovalent impurity-doped BNKT.

Dinh, Thi Hinh; Lee, Hyun-Young; Yoon, Chang-Ho; Malik, Rizwan Ahmed; Kong, Young-Min; Lee, Jae-Shin; Tran, Vu Diem Ngoc

2013-04-01

147

Adaptive hybrid control for linear piezoelectric ceramic motor drive using diagonal recurrent CMAC network  

Microsoft Academic Search

This work presents an adaptive hybrid control system using a diagonal recurrent cerebellar-model-articulation-computer (DRCMAC) network to control a linear piezoelectric ceramic motor (LPCM) driven by a two-inductance two-capacitance (LLCC) resonant inverter. Since the dynamic characteristics and motor parameters of the LPCM are highly nonlinear and time varying, an adaptive hybrid control system is therefore designed based on a hypothetical dynamic

Rong-Jong Wai; Chih-Min Lin; Ya-Fu Peng

2004-01-01

148

Study on controller designs for high-precisely linear piezoelectric ceramic motor (LPCM)  

Microsoft Academic Search

The aim of this paper is an observation of PID, fuzzy, sliding mode (SM) and fuzzy-sliding mode (FSM) controllers for high-precisely linear piezoelectric ceramic motor (LPCM). By understanding the characteristics of each single controller, one of the advantages is well-knowledge, when those controllers will be used, and what drawbacks they have. This paper exhibit a comparison of their error-reduction performance.

Hendro Nurhadi; Whei-Ming Kuo; Yeong-Shin Tarng

2010-01-01

149

Effects of static electric field on the fracture behavior of piezoelectric ceramics  

Microsoft Academic Search

The paper gives an overview on experimental observations of the failure behavior of electrically insulating and conducting\\u000a cracks in piezoelectric ceramics. The experiments include the indentation fracture test, the bending test on smooth samples,\\u000a and the fracture test on pre-notched (or pre-cracked) compact tension samples. For electrically insulating cracks, the experimental\\u000a results show a complicated fracture behavior under electrical and

Tong-Yi Zhang

2002-01-01

150

Analysis of Thin-Shell Piezoelectric Ceramics with Engineered Resonance Characteristics and Vibration Modes  

Microsoft Academic Search

Piezoelectric ceramic transducers with hollow thin shell forms (cylinder, tube, and cone) were fabricated by slip casting method. Characteristic vibration modes of the thin-shell structures were identified using finite element analysis method. Various vibration modes, such as length extension, radial expansion were obtained from the thin-shell transducers at 50-200 kHz frequencies. The resonance frequencies of these modes were engineered by

Sedat Alkoy

2006-01-01

151

Interdiffusion reaction in the PZT\\/PNN functionally gradient piezoelectric ceramic materials  

Microsoft Academic Search

The interfacial diffusion reaction between lead zirconate titanate (PZT) and lead nickel niobate (PbNi1\\/3Nb2\\/3O3:PNN) phases in the PZT\\/PNN functionally gradient piezoelectric ceramics were investigated as a function of the diffusion temperature and time, respectively. The ionic composition distribution profiles in the interdiffusion region were examined by electron probe microbeam analysis (EPMA). Based on a diffusion model of the overlapped diffusion

XINHUA ZHU; JIE XU; ZHONGYAN MENG

1998-01-01

152

Effect of (Mn, F) and (Mg, F) co-doping on dielectric and piezoelectric properties of lead zirconate titanate ceramics  

NASA Astrophysics Data System (ADS)

The influence of (Mn, F) and (Mg, F) dopants on the piezoelectric properties of lead zirconate titanate (PZT) ceramic compositions close to the morphotropic phase boundary is investigated. PZT ceramics are prepared by a chemical route based on co-precipitation of oxalates and hydroxides. The acceptor is incorporated into the B site of the materials and the fluorine ion is introduced into anionic sites. The d33 coefficient, the mechanical quality factor Qm and other properties are measured. Scanning electron microscopy is used to determine the grain size of the materials. Electron spin resonance is used to determine the valency state of Mn in fluorinated PZT ceramics. In Mn doped PZT, the introduction of a fluorine ion makes the poling process easier and increases the piezoelectric coefficients whereas the fluorination of Mg doped PZT constantly leads to hard materials with a lower piezoelectric response. This study shows that (Mn, F) co-doping produces semihard materials with high piezoelectric coefficients.

Boucher, E.; Guyomar, D.; Lebrun, L.; Guiffard, B.; Grange, G.

2002-11-01

153

Research on key technique of microscopy three-dimensional image reconstruction based on piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

Due to the limited depth of focus of microscope objective, a series of images taken from different sections and directions are needed to reconstruct 3D microscopy image. In this paper, we present a novel method which utilizes piezoelectric actuator, high magnification microscopy system without mirror and single CCD to observe micro-objects and reconstruct its three-dimensional image. Inverse piezoelectric effect of piezoelectric ceramics have some superior characteristics, such as high positioning resolution, high positioning accuracy, etc. And piezoelectric actuator possess the advantage of small-size, strong-power and easy- to-integrated as well. Based on these points, we designed a 360 rotation and tilt positioning platform. In this platform, Piezoelectric actuator is employed to ensure the positioning accuracy at axis-Z direction. At the same time, Motion of 360 rotation and tilt can be controlled precisely using stepping motor controlling technology. Furthermore, finite element methods (FEM) analyze software--ANSYS is used to analyze the rigidity, stress and structure optimization of the platform. This rotation and tilt mechanical positioning platform can help the single CCD to get clear, complete-view two dimensional images. This method paves the way for three-dimensional reconstruction of micro objects. Experiments demonstrate that this 360 rotation and tilt positioning stage is structure-simple and high-accurate. It can be widely used in micro-structure observing and three-dimensional image reconstruction among mechanics, materials and biology, etc.

Wang, Jianhua; Xiao, Zexin

2011-11-01

154

Enhanced ferroelectric and piezoelectric properties in doped lead-free (Bi0.5Na0.5)0.94Ba0.06TiO3 thin films  

Microsoft Academic Search

Doping effects with respect to the electrical properties of morphotropic phase boundary (Bi0.5Na0.5)0.94Ba0.06TiO3 thin films epitaxially grown on CaRuO3 electroded (LaAlO3)0.3(Sr2AlTaO6)0.35 (001) substrates were investigated. Substantial enhancement of ferroelectricity and piezoelectricity has been achieved in La+Ce codoped films with a remanent polarization Pr of 29.5 muC\\/cm2 and a remanent piezoelectric coefficient d33,f of 31 pm\\/V, whereas Mn doping seems more

D. Y. Wang; N. Y. Chan; S. Li; S. H. Choy; H. Y. Tian; H. L. W. Chan

2010-01-01

155

Enhanced ferroelectric and piezoelectric properties in doped lead-free (Bi0.5Na0.5)0.94Ba0.06TiO3 thin films  

Microsoft Academic Search

Doping effects with respect to the electrical properties of morphotropic phase boundary (Bi0.5Na0.5)0.94Ba0.06TiO3 thin films epitaxially grown on CaRuO3 electroded (LaAlO3)0.3(Sr2AlTaO6)0.35 (001) substrates were investigated. Substantial enhancement of ferroelectricity and piezoelectricity has been achieved in La+Ce codoped films with a remanent polarization Pr of 29.5 ?C\\/cm2 and a remanent piezoelectric coefficient d33,f of 31 pm\\/V, whereas Mn doping seems more

D. Y. Wang; N. Y. Chan; S. Li; S. H. Choy; H. Y. Tian; H. L. W Chan

2010-01-01

156

Electrical power generation characteristics of PZT piezoelectric ceramics  

Microsoft Academic Search

The electrical power generation characteristics of Mn-doped PZT ceramics responding to slow mechanical stress as well as to impact stress have been investigated. Although both the slow and impact stresses induce a reversible electrical response, the generation properties are distinctly different. Slow stress releases two output current peaks with opposite directions, responding to the increasing and decreasing part of the

Chao-Nan Xu; Morito Akiyama; Kazuhiro Nonaka; Tadahiko Watanabe

1998-01-01

157

Robust control for LLCC resonant linear piezoelectric ceramic motor drive  

Microsoft Academic Search

This study presents a robust control system for a linear ceramic motor (LCM) that is driven by a high-frequency voltage source inverter using LLCC resonant technique. Since the dynamic characteristics and motor parameters of the LCM are nonlinear and time varying, a robust control system is designed based on the hypothetical dynamic model to achieve high-precision position control. The presentation

Rong-Jong Wai; Rou-Yong Duan; Kuan-Yun Hsieh; Jeng-Dao Lee

2001-01-01

158

Grain Oriented Perovskite Layer Structure Ceramics for High-Temperature Piezoelectric Applications  

NASA Astrophysics Data System (ADS)

The perovskite layer structure (PLS) compounds have the general formula (A^{2+}) _2(B^{5+})_2 O_7, or (A^ {3+})_2(B^{4+ })_2O_7, and crystallize in a very anisotropic layered structure consisting of parallel slabs made up of perovskite units. Several of these compounds possess the highest Curie temperatures (T_{rm c} ) of any known ferroelectrics. Two examples are Sr_2Nb_2O _7 with T_{rm c} of 1342^circC, and La_2Ti_2O _7 with T_{rm c} of 1500^circC. This thesis is an investigation of PLS ceramics and their feasibility as a high temperature transducer material. Piezoelectricity in single crystals has been measured, but the containerless float zone apparatus necessary to grow high quality crystals of these refractory compounds is expensive and limited to a small number of research groups. Previous attempts to pole polycrystalline Sr_2Nb _2O_7 have failed, and to this point piezoelectricity has been absent. The initiative taken in this research was to investigate PLS ceramics by way of composition and processing schemes such that polycrystalline bodies could be electrically poled. The ultimate objective then was to demonstrate piezoelectricity in PLS ceramics, especially at high temperatures. Donor-doping of both La_2Ti _2O_7 and Sr_2Nb_2O _7 was found to increase volume resistivities at elevated temperatures, an important parameter to consider during the poling process. Sr_2Ta _2O_7 (T _{rm c} = -107 ^circC) was used to make solid solution compositions with moderately high Curie temperatures, of about 850^circC, and lower coercive fields. A hot-forging technique was employed to produce ceramics with high density (>99% of theoretical) and high degree of grain orientation (>90%). Texturing was characterized by x-ray diffraction and microscopy. Considerable anisotropy was observed in physical and electrical properties, including thermal expansion, resistivity, dielectric constant, and polarization. The direction perpendicular to the forging axis proved to be the ferroelectric "easy" direction, indicating that the polar axis lies in the plane of the plate-like grains. Hot-forged samples were poled at 40 to 50 KV/cm at 200^circC. Several compounds in the La_2Ti_2O _7-Sr_2Nb _2O_7-Sr _2Ta_2O_7 ternary system were shown to be piezoelectric. From appropriately oriented cuts, the dielectric, elastic, and piezoelectric coefficients were determined by the resonance method. Relative to commercial piezoelectric ceramics such as Pb(ZrTi)O_3, hot-forged PLS ceramics were found to have high frequency constants, low compliance, low electromechanical coupling, low piezoelectric coefficients, and high mechanical quality factors. For Sr_2(Nb_{0.5 }Ta_{0.5})_2 O_7, N_{32 } = 2216 Hz-m, s_{32} = 8.37 times 10^ {-12} m^2/N, k _{32} = 3.60%, d _{32} = 2.40 pC/N, and Q _{rm m} = 5290. This material was also shown to resist depoling when exposed to temperatures as high as 650^circC. Hot-forged PLS compounds offer a new family of ferroelectric ceramics that may prove to be useful as high temperature materials for electronic transducers or filters.

Fuierer, Paul Anton

159

Piezoelectric and dielectric aging of Bi0.5(Na0.82K0.18)0.5TiO3 lead-free ferroelectric thick films  

NASA Astrophysics Data System (ADS)

Ferroelectric Bi0.5(Na0.82K0.18)0.5TiO3 (NKBT) thick films have been prepared using screen printing on Pt electroded alumina substrates. The room-temperature dielectric constant of resulting 60 ?m thick NKBT film reaches as high as 823 at 1 kHz and the depolarization temperature, Td, locates at 130 C. The effect of amplitude and frequency of the applied ac field and the aging temperature as well as the Bi excess on the dielectric and piezoelectric aging characteristics are systemically studied. The results show that the dielectric and piezoelectric aging are associated with the reorientation of defect dipoles which stabilized the non-180 domain walls. By this reorientation the domain wall motions are clamped by a time dependent force resulting in the observed decrease in the dielectric and piezoelectric properties during the aging procedural. Moreover, the aging in NKBT thick films exhibits strong frequency dependence, which is caused by that the reorientation and alignment of the defect dipoles with the local polar domains provide a pinning field to the micropolar region, where the regions with larger micropolar volume will experience stronger pinning potential. The NKBT thick films added with 0.5 mol % Bi2O3 exhibit relative lower aging rate of the dielectric constant and piezoelectric coefficient, resulting from the compensation of the Bi3+ vacancies by the addition of small amount of excess Bi2O3.

Zhang, Haibo; Jiang, Shenglin; Xiao, Jianzhong; Kajiyoshi, Koji

2010-06-01

160

Piezoelectric Ceramics with Zero Temperature Coefficients of Radial Mode Resonance Frequencies  

NASA Astrophysics Data System (ADS)

Piezoelectric ceramics with zero temperature coefficients of radial mode resonance frequencies were developed. The chemical formula of these ceramics is (Pb0.91(La1-?Nd?)0.08)(Ti0.92Mn0.02In0.06)O3. In the ceramic system, the temperature coefficient varies from -25 10-6/C to +40 10-6/C as the molar ratio of Nd changes from 0 to 1. When ?{=}0.5, the temperature coefficient is less than 1 10-6/C over the temperature range -10 to +50C. The electromechanical coupling factor of radial mode is 0.1; mechanical qualityfactor is 1400; and dielectric constant \\varepsilon33T is 225.

Takeuchi, Hiroshi; Ito, Yukio; Nagatsuma, Kazuyuki; Jyomura, Shigeru; Ashida, Sakichi

1980-08-01

161

Dielectric and piezoelectric properties of microwave processed Sm substituted PCT ceramics  

NASA Astrophysics Data System (ADS)

The effect of samarium substitution on the structural, dielectric and piezoelectric properties of lead calcium titanate ceramics was investigated. Dense ceramics with nominal composition Pb0.76-3x/2SmxCa0.24Ti0.98Mn0.02O3 (x = 0-0.08) were fabricated by a novel, simple, energy and time efficient, and environment friendly microwave sintering process. The samples were sintered at 1100C for 30 min. All the compositions show single phase with tetragonal structure. Tetragonality decreases and relative density increases with increase in samarium substitution. The variation of the dielectric constant with temperature shows a ferroelectric phase transition and the transition temperature decreases with increase in the amount of samarium. Diffusivity increases with samarium substitution. All the compositions show well-defined ferroelectric behaviour. The electromechanical thickness coupling coefficient (kt) and piezoelectric longitudinal coefficient (d33) showed an increasing trend whereas the electromechanical planar coupling coefficient (kp) and the magnitude of the piezoelectric transverse longitudinal coefficient (d31) showed a decreasing trend with increase in samarium substitution level, which in turn results in an increase in electromechanical anisotropy.

Singh, Sarabjit; Thakur, O. P.; Prakash, Chandra

2005-05-01

162

Enhanced ferroelectric and piezoelectric properties in doped lead-free (Bi0.5Na0.5)0.94Ba0.06TiO3 thin films  

NASA Astrophysics Data System (ADS)

Doping effects with respect to the electrical properties of morphotropic phase boundary (Bi0.5Na0.5)0.94Ba0.06TiO3 thin films epitaxially grown on CaRuO3 electroded (LaAlO3)0.3(Sr2AlTaO6)0.35 (001) substrates were investigated. Substantial enhancement of ferroelectricity and piezoelectricity has been achieved in La+Ce codoped films with a remanent polarization Pr of 29.5 ?C/cm2 and a remanent piezoelectric coefficient d33,f of 31 pm/V, whereas Mn doping seems more favorite to reduce the leakage current by two order of magnitude. Both doped films exhibited diodelike I-V characteristics, which are correlated with resistance switching effect.

Wang, D. Y.; Chan, N. Y.; Li, S.; Choy, S. H.; Tian, H. Y.; Chan, H. L. W.

2010-11-01

163

Orientation-dependent piezoelectric properties in lead-free epitaxial 0.5BaZr0.2Ti0.8O3-0.5Ba0.7Ca0.3TiO3 thin films  

NASA Astrophysics Data System (ADS)

Orientation-engineered 0.5BaZr0.2Ti0.8O3-0.5Ba0.7Ca0.3TiO3 (BZT-BCT) thin films were deposited on La0.7Sr0.3MnO3-coated SrTiO3 single-crystalline (001), (110), and (111) substrates by off-axis radio-frequency magnetron sputtering. X-ray diffraction confirmed a highly epitaxial growth of all the as-deposited films. It is believed the strong orientation dependence of ferroelectric and piezoelectric properties on the films is attributed to the relative alignment of crystallites and spontaneous polarization vector. The optimal ferroelectric response lies in the [001] direction, whereas a comparatively large effective piezoelectric coefficient d33,eff of 100.1 +/- 5 pm/V was attained in [111] BZT-BCT thin film, suggesting its potential application for high-performance lead-free piezoelectric devices.

Luo, B. C.; Wang, D. Y.; Duan, M. M.; Li, S.

2013-09-01

164

Design and characterization of a carbon-nanotube-reinforced adhesive coating for piezoelectric ceramic discs  

NASA Astrophysics Data System (ADS)

The silver paste electrode of piezoelectric (PZT) ceramic discs has been shown to produce a weak interface bond between a bare PZT and its paste coating under a peeling force. In this work, an investigation was conducted to reinforce the bond with a high density array of oriented carbon nanotube nano-electrodes (CNTs-NEA), between a bare PZT ceramic and a metal substrate. The ensuing design and fabrication of a carbon-nanotube-coated piezoelectric disc (CPZT) is presented along with a study of the bondline integrity of a CPZT mounted on a hosting structure. The CPZT has its electrode silver paste coating replaced with a high density array of CNTs-NEA. Mechanical tests were performed to characterize the shear strength of the bondline between CPZT discs and the substrate. The test results were compared with shear strengths of the bondlines made of pure non-conductive adhesive and adhesive with randomly mixed CNTs. The comparison showed the oriented CNT coating on PZTs could significantly enhance the interfacial shear strength. Through the microscopic examination, it was evident that the ratio between the CNT length (Lc) and the bond thickness (H) significantly influenced the bond strength of CPZT discs. Three major interface microstructure types and their corresponding failure modes for specific Lc/H values were identified. The study also showed that failure did not occur along the interface between the PZT ceramic element and the CNT coating.

Lanzara, G.; Chang, F.-K.

2009-12-01

165

Dielectric and Piezoelectric Properties of 10% KF-Doped BaTiO3 Ceramics  

NASA Astrophysics Data System (ADS)

10% KF-doped barium titanate powders, Ba0.9K0.1TiO2.9F0.1, were synthesized through a sol-gel process. The powders, calcined at 650 C, consist of cubic crystalline particles of 70 nm in length; the particle size increases to 200 nm as the firing temperature increases to ca. 800 C, above which F2 begins to evaporate. Dense ceramics were fabricated by the spark plasma sintering (SPS) method; the average grain size is 2 ?m in lengths. The ceramics, well annealed at 1,000 C in an O2 gas flow, have good dielectric and piezoelectric properties; the piezoelectric d33 value is 230 pC/N at room temperature. At the ferroelectric Curie temperature TC = 47 C, the dielectric constant and loss \\tan? are 10,000 and <5% at 10 kHz, respectively. The Curie-Weiss relation holds in the fully disordered cubic and ordered rhombohedral phases, showing the second order 1:2 relation. Below 10 kHz, large dielectric dispersion caused by a domain-wall motion appears at the temperature range of -50 to 107 C. Some discussions are made for these dielectric properties of the ceramics.

Akishige, Yukikuni; Hiraki, Yuuta; Tsukada, Shinya; Xu, Jun; Morito, Shigekazu; Ohba, Takuya; Lee Walker, Ezekiel; Neogi, Arup

2010-08-01

166

Design of Translation Rotary Ultrasonic Motor with Slanted Piezoelectric Ceramics  

NASA Astrophysics Data System (ADS)

We designed and manufactured a multi-degree-of-freedom (MDoF) ultrasonic motor (USM) by using a single actuator. Although there have been numerous MDoF USMs reported in the literature, only a few of them cover the combined rotary and translational motions in a cylindrical-joint type configuration. Combining these two motions in one joint and controlling this combined motion through a novel USM is the main aim of this work. Here, we use smooth impact drive method (SIDM) with two distinct modes obtained at two distinct frequencies by the help of slanted ceramics and uneven square shaped excitation signals. The translational-rotary dual-mode motor can be driven by single source. The prototype of the motor (5 mm diameter, 25 mm total length) has 5 mm/s translational and 3 rad/s rotary speed under 4 mN blocking force, when the input signal is 20 Vp--p square wave.

Tuncdemir, Safakcan; Ural, Seyit O.; Koc, Burhanettin; Uchino, Kenji

2011-02-01

167

Transducer Performance for Leaky Wave in Layered Structure of Piezoelectric Ceramic Thin Plate and Acryl Plate  

NASA Astrophysics Data System (ADS)

A leaky wave transducer in the combination of a piezoelectric ceramic thin plate and an acryl plate is described, which functions as a transducer for underwater ultrasound. The operation performance of an interdigital transducer in the layered structure is described from the viewpoint of phase velocity, electromechanical coupling constant, mode conversion efficiency and transducer efficiency. The leaky wave transducer has multiple modes with velocity dispersion. Using the second-order anti-symmetrical mode with high transducer efficiency value, a liquid-delay line oscillation is demonstrated.

Toda, Kohji; Akutsu, Yasuhiko

1994-09-01

168

Impedance-spectroscopy analysis and piezoelectric properties of Pb 2KNb 5O 15 ceramics  

Microsoft Academic Search

Preparation, dielectric, piezoelectric, hysteresis, impedance spectroscopy and AC conductivity studies in the Pb0.8K0.4Nb2O6 ferroelectric ceramic have been presented. The Pb1?xK2xNb2O6 (PKN) characterized for ferroelectric and impedance spectroscopy studies from room temperature to 600C. The sample shows a single phase with orthorhombic structure from X-ray diffraction studies. The ColeCole plots and electric modulus plots at different temperatures are drawn. The results

K. Sambasiva Rao; P. Murali Krishna; T. Swarna Latha; D. Madhava Prasad

2006-01-01

169

Piezoelectric and Dielectric Properties of PMN-PNN-PZT Ceramics with the Variation of High Energy Ball Milling Time  

Microsoft Academic Search

In this study, in order to develop the composition ceramics for low temperature sintering multilayer piezoelectric actuator, Pb(Mn1\\/3Nb2\\/3)O3?Pb(Ni1\\/3Nb2\\/3)O3? Pb(Zr0.48Ti0.51)O3 (abbreviated as PMN-PNN-PZT) ceramics were fabricated using Li2CO3, Na2CO3 and ZnO as sintering aids and according to the Ball milling time. And also, their dielectric and piezoelectric properties were investigated. At the High Energy Ball Milling (HEBM) time of 9 h

Yu Hyong Lee; Ju Hyun Yoo

2010-01-01

170

Dielectric and piezoelectric properties in the lead-free system Na0.5K0.5NbO3-BiScO3-LiTaO3.  

PubMed

Phase relations, dielectric and piezoelectric properties are reported for the ternary system 98%[(1 - x) (Na(0.5)K(0.5)NbO(3))-x(LiTaO(3))]-2%[BiScO(3)] for compositions x ? 10 mol% LiTaO(3). The phase content at room-temperature changed from mixed phase, monoclinic + tetragonal, for unmodified 98%(Na(0.5)K(0.5)NbO(3))-2%(BiScO(3)), to tetragonal phase for compositions >2 mol% LiTaO(3). Curie peaks at 360 to 370C were observed for all compositions, but peaks became diffuse at x ? 3 mol%, and two dielectric peaks, at 370 and 470C, were observed for 5 mol% LiTaO(3). Phase segregation, and finite size affects associated with the core-shell structure, account for the occurrence of two dielectric peaks in 5 mol% LiTaO(3), and diffuse dielectric behavior. The value of d(33) piezoelectric charge coefficient increased from ~160 pC/N for 0 mol% LiTaO(3) to 205 to 214 pC/N for 1 to 2 mol% LiTaO3 solid solutions, before falling sharply at 3 mol% LiTaO(3). TEM-EDX analysis revealed core-shell grain structures with segregation of Bi, Sc, and Ta in the outer ~100-nm shell of the 5 mol% LT sample. PMID:21937312

Zhu, Fangyuan; Ward, Michael B; Comyn, Tim P; Bell, Andrew J; Milne, Steven J

2011-09-01

171

Characterization of piezoelectric ceramics and 1-3 composites for high power transducers  

PubMed Central

The high power characteristics of various piezoelectric ceramics and 1-3 composites were investigated. In contrast to hard Pb(Zr,Ti)O3, modified (Bi0.5Na0.5)TiO3 based ceramics were found to show a relatively linear electromechanical response under high drive conditions due to their high stability of mechanical quality factor. The effects of high drive field and duty cycle on the behavior of 1-3 composites were analyzed by varying active and passive components. Improved high power characteristics of 1-3 composites were achieved by selection of optimized composite components, with enhanced electromechanical efficiency and thermal stability under high drive conditions.

Jae Lee, Hyeong; Zhang, Shujun; Meyer, Richard J.; Sherlock, Nevin P.; Shrout, Thomas R.

2012-01-01

172

Enhanced ferroelectric and piezoelectric response in Mn-doped Bi0.5Na0.5TiO3BaTiO3 lead-free film by pulsed laser deposition  

NASA Astrophysics Data System (ADS)

Mn-doped Bi0.5Na0.5TiO3BaTiO3 thin film with the composition around the morphotropic phase boundary was grown on Pt-electrodized Si substrate by pulsed laser deposition. Highly (1 0 0)-oriented film with pure perovskite structure was obtained through carefully controlling the growth conditions. Well-defined ferroelectric PE loop was obtained with the average remnant polarization Pr and coercive field Ec of 11.3 ?C/cm2 and 6.5 kV/mm, respectively. Polycrystalline structures and multidomain states were revealed by piezoresponse force microscopy and large local strain response was obtained with the normalized strain Smax/Emax up to 92 pm/V. The excellent global electrical properties make it quite promising in environmental-friendly ferroelectric and piezoelectric devices.

Jin, Chengchao; Wang, Feifei; Leung, Chung Ming; Yao, Qirong; Tang, Yanxue; Wang, Tao; Shi, Wangzhou

2013-10-01

173

Structural, dielectric relaxation and piezoelectric characterization of Sr2+ substituted modified PMS-PZT ceramic  

NASA Astrophysics Data System (ADS)

Pyrochlore phase free [Pb0.94Sr0.06] [(Mn1/3Sb2/3)0.05(Zr0.53Ti0.47)0.95] O3 ceramics has been synthesized with pure Perovskite phase by semi-wet route using the columbite precursor method. The field dependences of the dielectric response and the conductivity have been measured in a frequency range from 50 Hz to 1 MHz and in a temperature range from 303 K to 773 K. An analysis of the real and imaginary parts of the dielectric permittivity with frequency has been performed, assuming a distribution of relaxation times. The scaling behavior of the dielectric loss spectra suggests that the distribution of the relaxation times is temperature independent. The SEM photographs of the sintered specimens present the homogenous structures and well-grown grains with a sharp grain boundary. The material exhibits tetragonal structure. When measured at frequency (100 Hz), the polarization shows a strong field dependence. Different piezoelectric figures of merit (kp, d33 and Qm) of the material have also been measured obtaining their values as 0.53, 271 pC/N and 1115, respectively, which are even higher than those of pure PZT with morphotropic phase boundary (MPB) composition. Thus the present ceramics have the optimal overall performance and are promising candidates for the various high power piezoelectric applications.

Brajesh, Kumar; Himanshu, A. K.; Sharma, Himanshu; Kumari, Kiran; Ranjan, Rajeev; Bandhopadhyay, S. K.; Sinha, T. P.

2012-02-01

174

Ultrasound radiation into water by a Lamb wave device using a piezoelectric ceramic plate with spatially varying thickness  

Microsoft Academic Search

The operation of a Lamb wave device, using an interdigital transducer and a piezoelectric ceramic plate with spatially varying thickness, is investigated both theoretically and experimentally to understand the characteristics of ultrasound radiation into water that accompanies Lamb wave propagation. A new calculation model for Lamb wave propagation in a water-loaded inhomogeneous plate is established and the Lamb wave velocities

Kenji Motegi

1999-01-01

175

Development of lead-free single-element ultrahigh frequency (170-320MHz) ultrasonic transducers.  

PubMed

This paper presents the design, fabrication and characterization of single-element ultrahigh frequency (UHF) ultrasonic transducers in which the center frequency ranged from 170 to 320MHz. The center frequency of >300MHz is the highest value of lead-free ceramic ultrasonic transducers ever reported. With concern in the environmental pollution of lead-based materials, the transducer elements presented in this work were lead-free K0.5Na0.5NbO3/Bi0.5Na0.5TiO3 (KNN/BNT) composite thick films. All transducers were evaluated in a pulse-echo arrangement. The measured -6dB bandwidth of the transducers ranged from 35% to 64%. With the optimized piezoelectric properties of the composite film, the insertion loss of the UHF transducers was measured and determined to range from -50 to -60dB. In addition to the pulse-echo measurement, a 6?m tungsten wire phantom was also imaged with a 205MHz transducer to demonstrate the imaging capability. The measured -6dB axial and lateral resolutions were found to be 12?m and 50?m, respectively. The transducer performance presented in this work is shown to be better or comparable to previously reported results even though the frequency is much higher. PMID:23485349

Lam, Kwok Ho; Ji, Hong Fen; Zheng, Fan; Ren, Wei; Zhou, Qifa; Shung, K Kirk

2013-02-08

176

Phase diagram and structure-property relationships in the lead-free piezoelectric system: Na0.5K0.5NbO3-LiTaO3.  

PubMed

A phase-diagram for the Na(0.5)K(0.5)NbO(3)-LiTaO(3) solid solution series (NKN-LT) is presented for compositions ? 10 mol% LT, based on the combined results of temperaturevariable X-ray powder diffraction and dielectric measurements. In addition to the reported orthorhombic and tetragonal polymorphs of NKN-LT, a monoclinic phase is revealed. Changes to electrical properties as a function of LT substitution are correlated to phase content. Increasing the LT content from 5 to 7 mol% LT led to improved temperature stability of piezoelectric properties because of the avoidance of the monoclinic-tetragonal polymorphic phase transition during thermal cycling (at >25C). For 7 mol% LT samples: d(33) = 200 pC/N; T(c) = 440C; ?(r) = 550 and tan ? = 0.02 (at 20C). Modification of this composition by solid solution with BiScO(3) led to a decrease in d(33) values. Transmission electron microscopy of a sample of 0.95[0.93 NKN-0.07LT]-0.05BiScO(3) indicated a core-shell grain structure which led to temperature-stable dielectric properties. PMID:21937313

Skidmore, Thomas A; Comyn, Timothy P; Bell, Andrew J; Zhu, Fangyuan; Milne, Steven J

2011-09-01

177

High temperature (NaBi)0.48?0.04Bi2Nb2O9-based piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

The effect of (LiCe) substitution for A site on the properties of (NaBi)0.48?0.04Bi2Nb2O9 (NB?N)-based ceramics was investigated. The coercive fields (EC) of NB?N)-based ceramics were significantly decreased from 61.0 to 32.5 kV/cm and the Curie temperature (TC) gradually decreases from 820 to 803 C with increasing the (LiCe) modification. The piezoelectric coefficient d33, planar coupling factor kp, and mechanical quality factor Q of (NaBi)0.38(LiCe)0.05?0.14Bi2Nb2O9 ceramic were found to be 27 pC/N, 11.2%, and 2600, respectively, together with the high TC (~809 C) and stable piezoelectric properties, demonstrating that the (LiCe) modified NB?N-based material a promising candidate for high temperature applications.

Gai, Zhi-Gang; Wang, Jin-Feng; Zhao, Ming-Lei; Wang, Chun-Ming; Zang, Guo-Zhong; Ming, Bao-Quan; Qi, Peng; Zhang, Shujun; Shrout, Thomas R.

2006-07-01

178

Assessing lead-free intellectual property  

Microsoft Academic Search

This paper presents the analysis of information collected from numerous patent searches on lead-free alloys. The significance of claim structure and content is discussed in view of the growing number of lead-free patents. Patent analysis software was developed to effectively compare over 350 lead-free alloy patents. A case study was conducted to assess Sn-Ag-Cu and special purpose lead-free candidate alloy

Paul Casey; Michael Pecht

2004-01-01

179

Feasibility study of shape control with zero applied voltage utilizing hysteresis in strain-electric field relationship of piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

To keep a shape of a smart structure controlled by piezoelectric actuators attached to it, electric voltage must be also continued to be applied. To reduce amount of electricity usage, a new control method is proposed. In this method strains of the piezoelectric actuators generated by pulses of voltages are kept with zero/less applied voltage by utilizing the hysteresis in strain versus electric field relationship effectively. In this paper to examine feasibility of this control method residual strains of piezoelectric ceramic plates are measured for combinations of amplitude and period of the applied pulse of voltages. Moreover, a cantilever beam on which a piezoelectric ceramic plate is bonded is made as a simple example of applications to the smart structures, and its deformation behavior after a pulse of voltage is observed. The result shows that the present control method is useful from viewpoint of applied energy, although the strain generated by the piezoelectric actuator is less than the conventional control method where the electric voltage is continued to be applied.

Ikeda, T.; Takahashi, T.

2013-04-01

180

Lead-free electric matches.  

SciTech Connect

Electric matches are used in pyrotechnics to initiate devices electrically rather than by burning fuses. Fuses have the disadvantage of burning with a long delay before igniting a pyrotechnic device, while electric matches can instantaneously fire a device at a user's command. In addition, electric matches can be fired remotely at a safe distance. Unfortunately, most current commercial electric match compositions contain lead as thiocyanate, nitroresorcinate or tetroxide, which when burned, produces lead-containing smoke. This lead pollutant presents environmental exposure problems to cast, crew, and audience. The reason that these lead containing compounds are used as electric match compositions is that these mixtures have the required thermal stability, yet are simultaneously able to be initiated reliably by a very small thermal stimulus. A possible alternative to lead-containing compounds is nanoscale thermite materials (metastable intermolecular composites or MIC). These superthermite materials can be formulated to be extremely spark sensitive with tunable reaction rate and yield high temperature products. We have formulated and manufactured lead-free electric matches based on nanoscale Al/MoO{sub 3} mixtures. We have determined that these matches fire reliably and to consistently ignite a sample of black powder. Initial safety, ageing and performance results are presented in this paper.

Son, S. F. (Steven F.); Hiskey, M. A. (Michael A.); Naud, D. (Darren); Busse, J. R. (James R.); Asay, B. W. (Blaine W.)

2002-01-01

181

Investigation on piezoelectric ceramics with high d33, d 31 for a new type of rotational stepper motor  

Microsoft Academic Search

A quarternary system ceramic with high piezoelectric constants, particularly a high d31 and high d33, was studied. The composition of the materials is PMN-PNN-PZT doped with oxides of Sr, Bi, Sn and La etc. The properties of the materials are as follow: d33=(600-750)10-12C\\/N, d31=(-300-398)10-12C\\/N, Kp=0.68-0.75. By using this material, a new type of rotational stepper motor, a piezoelectric electro-rheological motor

Zhilun Gui; Wei Zhong; Shuxiang Dong; Longtu Li; Xiaowen Zhang

1994-01-01

182

Dielectric, piezoelectric, and pyroelectric properties of lead zirconate-lead zinc niobate ceramics  

SciTech Connect

This paper reports on piezoelectric and pyroelectric ceramics consisting of antiferroelectric lead zirconate (PZ) and relaxor ferroelectric lead zinc niobate (PZN) studied from an application viewpoint of the field-induced antiferroelectric-to-ferroelectric phase transition. An antiferroelectric-to-ferroelectric phase transition. An antiferroelectric-ferroelectric phase boundary exists in PbZr{sub x}(Zn{sub 1/3}Nb{sub 2/3}){sub 1 {minus} x}O{sub 3}(PZZN-1000x) close to x = 0.93 to 0.94 at room temperature. A new ferroelectric rhombohedral phase change, F{alpha}-F'{alpha} at low temperature is found and studied by the temperature dependence of the pyroelectric coefficient. Electrical poling in these ceramics is easy, and the coercive field E{sub c} {approx} 8 to 10 kV/cm is rather low. Samples with compositions in the range PZZN-86 to PZZN-92 have a large electromechanical coupling constant, k (k, and k {sub 15} {approx} 50% to 60%), and a low dielectric constant, {epsilon}{sub s}, ({epsilon}{sup T}{sub 33}/{epsilon}{sub 0} = 260 to 320, {epsilon}{sup T}{sub 11} {epsilon}{sub 0} = 380). PZZN ceramics appear to be potential candidates for high-frequency ultrasonic transducers used in the thickness shear mode. The pyroelectric figure of merit (F{sub v}) of these ceramics is comparable to the values published for the PZT-based or PbTiO{sub 3}-based materials.

Takenaka, T. (Science Univ. of Tokyo (Japan)); Bhalla, A.S.; Cross, L.E. (Pennsylvania State Univ., University Park, PA (United States). Materials Research Lab.); Sakata, K. (Science Univ. of Tokyo, Noda, Chiba (Japan). Faculty of Science and Technology)

1989-06-01

183

Piezoelectric Properties of Low Loss and Low Temperature sintering PMN-PNN-PZT Ceramics According to the Amount of MnO2 Addition  

Microsoft Academic Search

In this study, in order to develop the composition ceramics for low loss and low temperature sintering multilayer piezoelectric actuator, PMN-PNN-PZT ceramics were fabricated using Li2CO3 and Na2CO3 as sintering aids, and their piezoelectric and dielectric characteristics were investigated according to the amount of MnO2 addition. At the sintering temperature of 900 , density and mechanical quality factor (Qm) of

Juhyun Yoo; Sangho Lee; Lakhoon Hwang; Yeongho Jeong

2006-01-01

184

The effect of high energy mechanochemical processing on the microstructure, piezoelectric, ferroelectric and mechanical properties of PLZT ceramics.  

PubMed

Lead lanthanum zirconate titanate (PLZT) ceramics were synthesized using a high energy mechanochemical processing technique, using tungsten carbide grinding vials and balls. The ceramic powders were prepared using the constituent oxide powders, which were subjected to high energy milling, without the use of any excess PbO in the starting composition. TEM studies revealed the formation of very fine particles of the order of 30nm, due to the milling effect. Highly dense ceramics could be prepared via sintering which resulted in ultra-high strains in these piezoelectric samples of up to 0.25%, a value which has not been reported hitherto by any other known process. The effect of the reduction in particle size on the microstructure, mechanical and electrical properties of PLZT ceramics were studied and are discussed herein. PMID:21825708

James, A R; Chandra Rao, B S S; Pathak, Mohan; Kamat, S V; Subrahmanyam, J

2008-04-07

185

EPMA and TEM investigations on the interdiffusion layer of the PNN\\/PZT functionally gradient piezoelectric ceramics  

Microsoft Academic Search

The compositional profile, distribution of the phases and the ordering behavior in the interdiffusion layer of the PNN\\/PZT functionally gradient piezoelectric ceramics have been investigated by electron probe microbeam analyses (EPMA) and transmission electron microscopy (TEM) respectively. The results show that the thickness of the interdiffusion layers (d) for Ni2+, Nb5+, Ti4+ and Zr4+ ions are ordered as dNi2+ >

Xinhua Zhu; Jianmin Zhu; Shunhua Zhou; Qi Li; Zhiguo Liu; Naiben Ming; Zhongyan Meng

2000-01-01

186

Microstructure, Phase Transition, and Electrical Properties of K x Na1- x NbO3 Lead-Free Piezoceramics  

NASA Astrophysics Data System (ADS)

The microstructure, phase transition, and electrical properties of lead-free K x Na1- x NbO3 ( x = 0.46 to 0.51, abbreviated as KNN) piezoceramics prepared by a conventional solid-state reaction method were investigated with an emphasis on the influence of the K/Na ratio. Scanning electron microscopy (SEM) images showed that the grain growth was slightly improved by increasing x. However, all ceramic samples possessed high densifications with fine grains from several hundred nanometers to several micrometers. X-ray diffraction (XRD) results showed that a discontinuous change of lattice parameters appeared between x = 0.49 and 0.50, which suggested a typical morphotropic phase boundary (MPB) separating two different orthorhombic phases O I and O II. The sample with composition x = 0.49 had the peak values of the piezoelectric constant d 33 of 146 pC/N and the planar electromechanical coupling coefficient k p of 43%. These results indicated that improving the piezoelectric properties in KNN ceramics could be achieved by optimizing the K/Na ratio.

Li, Y. M.; Shen, Z. Y.; Jiang, L.; Liao, R. H.; Wang, Z. M.; Hong, Y.

2012-03-01

187

Effects of the Calcining Temperature on the Piezoelectric and Dielectric Properties of 0.55PNN-0.45PZT Ceramics  

Microsoft Academic Search

The 0.55Pb(Ni1\\/3Nb2\\/3)O30.45Pb(Zr0.3Ti0.7)O3 (0.55PNN-0.45PZT) ceramics were prepared by conventional solid state reactions. The effects of calcining temperature on the particle size and piezoelectric properties of 0.55PNN-0.45PZT piezoelectric ceramics were investigated. The particle size and crystallinity of 0.55PNN-0.45PZT ceramic powders are influenced by calcining temperature, and therefore the microstructure and final piezoelectric properties of 0.55PNN-0.45PZT are different. The highest piezoelectric properties (d33

Jun Luo; Jinhao Qiu; Kongjun Zhu; Jianzhou Du; Xuming Pang; Hongli Ji

2011-01-01

188

Crystal structure analysis of lead free Ba1-xLax[Ti0.5(Fe0.5Nb0.5)0.5]1-x/4O3 Ceramics  

NASA Astrophysics Data System (ADS)

Single phase Ba1-xLax[Ti0.5(Fe0.5Nb0.5)0.5]1-x/4O3 [referred as BT-LFN]; x=0, 0.02, 0.04 and 0.06 ceramics have been synthesized by solid - state reaction process and were characterized by X-ray diffraction technique. The microstructure of the ceramics was examined by field emission-scanning electron microscopy (FE-SEM).

Patel, Piyush Kumar; Rani, Jyoti; Yadav, K. L.

2012-06-01

189

Recurrent fuzzy neural network control for piezoelectric ceramic linear ultrasonic motor drive.  

PubMed

In this study, a recurrent fuzzy neural network (RFNN) controller is proposed to control a piezoelectric ceramic linear ultrasonic motor (LUSM) drive system to track periodic reference trajectories with robust control performance. First, the structure and operating principle of the LUSM are described in detail. Second, because the dynamic characteristics of the LUSM are nonlinear and the precise dynamic model is difficult to obtain, a RFNN is proposed to control the position of the moving table of the LUSM to achieve high precision position control with robustness. The back propagation algorithm is used to train the RFNN on-line. Moreover, to guarantee the convergence of tracking error for periodic commands tracking, analytical methods based on a discrete-type Lyapunov function are proposed to determine the varied learning rates of the RFNN. Then, the RFNN is implemented in a PC-based computer control system, and the LUSM is driven by a unipolar switching full bridge voltage source inverter using LC resonant technique. Finally, the effectiveness of the RFNN-controlled LUSM drive system is demonstrated by some experimental results. Accurate tracking response and superior dynamic performance can be obtained because of the powerful on-line learning capability of the RFNN controller. Furthermore, the RFNN control system is robust with regard to parameter variations and external disturbances. PMID:11477782

Lin, F J; Wai, R J; Shyu, K K; Liu, T M

2001-07-01

190

A study of electromechanical properties of PMN-PT ceramics and analysis of the effects of loss on frequency response of piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

Two areas of piezoelectric ceramic research are discussed. First, a study of structure-property relations in PMN-PT is presented. Then, results of a study of effects of various loss mechanisms in ceramic resonators are given. Ceramic lead magnesium niobate-lead titanate ((1-x)PMN-xPT) of different compositions was prepared by the columbite precursor method. This study covers compositions ranging from 0.94PMN-0.06PT to 0.60PMN-0.40PT, focusing on two areas of the (1-x)PMN-xPT system: compositions that exhibit electrostrictive behavior and those that show piezoelectric behavior. Optimal electromechanical properties are obtained with the composition 0.82PMN-0.18PT, measured at T=Tsb{m}=80spC and with a DC bias of 5 kV/cm. Under these conditions the dielectric constant is 32000 and the planar coupling coefficient is 0.55. X-ray diffraction is used to study crystal structure of the (1-x)PMN-xPT system near the morphotrophic phase boundary (MPB). In this study, it is shown that the (1-x)PMN-xPT system has a compositionally wide two-phase region surrounding the MPB. The compositions 0.72PMN-0.28PT and 0.60PMN-0.40PT correspond to the rhombohedral and tetragonal single phase boundaries of the two-phase region, respectively, and 0.655PMN-0.345PT is the MPB composition. Electromechanical property evaluation shows that the optimal piezoelectric properties (dsb{33}=720 pC/N, K = 5400, ksb{p} = 62%, and ksb{t} = 46%) are obtained at the MPB composition. A review of work involving loss in ceramic resonators represented via complex material constants and equivalent circuits from past literature is presented. The concept of a complex electromechanical coupling coefficient is presented, and its connection to complex material constants is discussed. The complex electromechanical coupling coefficient results directly from the complex material constants from which it is comprised. As a consequence of the complex electromechanical coupling coefficient, complex resonance frequencies arise and are presented. This means that the natural resonance frequencies of a lossy piezoelectric material are in complex frequency space and, if stimulated near a complex frequency, will exhibit typical piezoelectric frequency response profiles. An example, using computer simulation, is presented using the MPB composition of PMN-PT to show its complex resonance frequency and behavior when subject to excitation by complex frequencies. When excited with a complex frequency voltage source, the measured current response attains a maximum value at the natural (complex) resonance frequency.

Kelly, Joseph Martin

191

The effects of porosity, electrode and barrier materials on the conductivity of piezoelectric ceramics in high humidity and dc electric field  

NASA Astrophysics Data System (ADS)

Prolonged operation of piezoelectric ceramic devices under high dc electric fields promotes leakage currents between the electrodes. This paper investigates the effects of ceramic porosity, edge conduction and electrode materials and geometry in the development of low resistance conduction paths through the ceramic. Localized changes in the ceramic structure and corresponding microscopic breakdown sites are shown to be associated with leakage currents and breakdown processes resulting from prolonged operation in harsh environments. The role of barrier coatings in mitigating the effects of humidity is studied, and results are presented on improved performance using composite diamond-like carbon/polymer coatings. In contrast to the changes in the electrical properties of the ceramic, the measurements of the piezoelectric properties showed no significant effect of humidity.

Weaver, P. M.; Cain, M. G.; Stewart, M.; Anson, A.; Franks, J.; Lipscomb, I. P.; McBride, J. W.; Zheng, D.; Swingler, J.

2012-04-01

192

Processing and properties of bismuth sodium titanate-based piezoelectric ceramics for transducer applications  

NASA Astrophysics Data System (ADS)

Piezoelectric ceramics have been key materials for transducer applications. Most practical materials are developed from the binary and ternary systems of lead-based perovskite piezoceramics. The main drawbacks of these lead-based materials include processing of PbO and, also, PbO evaporation during sintering, leading to a serious pollution problem. The toxicity and volatility of lead oxide are critical environmental issues which cannot be overlooked. Through the concept of Smolenskii, it is possible to replace Pb with elements having similar electron configuration and still obtain a material exhibiting similar behavior in spontaneous polarization. The Bisb{0.5}Nasb{0.5}TiOsb3 (BNT) composition has a perovskite structure and presents ferroelectric behavior with a Curie temperature of 320spC. However, the random displacement between the Nasp+ and Bisp{3+} ions at elevated temperature results in the abnormal dielectric permittivity and loss as functions of temperature and frequency. Additionally, the high coercive field of this BNT composition (Esbc = 70 kV/cm) leads to a difficulty in successful poling. In this research, the structure-processing-properties relations of BNT and solid solutions of BNT with Pbsb{0.75}Casb{0.25}TiOsb3 were assessed. Based on the flexibility of the perovskite structure in allowing an incorporation of various cation sizes, isovalent and aliovalent substitutions were utilized in the compositional modification of BNT. These modified BNT compositions were formulated by the conventional mixed oxide method, following optimized powder processing, specimen fabrication, and sintering procedures. Two kinds of distortion from the ideal perovskite structure, the packing and off-center effects, were expected to be involved in this modification. A series of the modified BNT piezoceramics encompassing various dielectric and piezoelectric properties was prepared by the addition of three rare-earth ions, Lasp{3+}, Ndsp{3+}, and Smsp{3+}, and a pentavalent ion, Nbsp{5+}. These modified BNT compositions were calcined in the range of 800-900spC for 2-5 hrs and then sintered at 1050-1200spC for 1-4 hrs. Conventional poling was performed at 50spC with an applied field of 40-70 kV/cm for 5 minutes. A composition of the BNT with 0.5 at% La yielded a K value of 515, ksb{t} of 45%, dsb{33} of 100 pC/N, dsb{h} of 65 pC/N and ksb{t}/ksb{p} of 3.5, which is considerable promising for transducer applications.

Herabut, Aree

1997-11-01

193

New lead-free solder alloy  

Microsoft Academic Search

As the electronics industry is moving towards lead-free manufacturing processes, a new lead-free solder alloy based on Sn9Zn1Bi2CuIn is described. The quaternary alloy with indium additions exhibits melting, wetting, and mechanical properties superior to those in binary, ternary, and quaternary alloys. Indium as a penternary addition decreases the melting point of this alloy to 181C which it is a lower

Mustafa Kamal; M. S. Meikhail; Abu Bakr El-Bediwi; El-Said Gouda

2005-01-01

194

High piezoelectric properties and domain configuration in BaTiO3 ceramics obtained through the solid-state reaction route  

NASA Astrophysics Data System (ADS)

BaTiO3 ceramics with a high piezoelectric coefficient have been successfully obtained through the conventional solid-state reaction route starting from ordinary BaCO3 and TiO2 powders. The ceramics sintered at 1210 C exhibit excellent piezoelectric properties of d33 = 419 pC N-1 and kp = 0.453 with tan ? = 1.36% at room temperature. The crystallographic structure, the microstructure and the domain pattern were investigated. It has been revealed that d33 increases and the average domain width in the poled BaTiO3 ceramics remains approximately constant at around 240 nm with the decrease in the average grain size from 9.5 to 2.0 m. From the analysis, we suggest that the largeness of the domain wall is an important factor, which significantly influences the piezoelectric properties.

Shao, Shoufu; Zhang, Jialiang; Zhang, Zong; Zheng, Peng; Zhao, Minglei; Li, Jichao; Wang, Chunlei

2008-06-01

195

Piezoelectric and dielectric characteristics of low temperature sintering Pb(Ni 1\\/3 Nb 2\\/3 )O 3 Pb(Mn 1\\/3 Nb 2\\/3 )O 3 Pb(Zr 1\\/2 Ti 1\\/2 )O 3 ceramics for multilayer piezoelectric actuator  

Microsoft Academic Search

In this study, in order to develop the composition ceramics for multilayer piezoelectric actuator, PNN substituted PMN-PZT\\u000a ceramics were fabricated using Li2CO3 and Na2CO3 as sintering aids, and their piezoelectric and dielectric characteristics were investigated. With the increase of the amount\\u000a of PNN substitution, dielectric constant (?r), electromechanical coupling factor (k\\u000a p), and piezoelectric constant (d\\u000a 33) of specimens showed

Juhyun Yoo; Jungmin Hwang; Sangho Lee; Kwanghyun Chung; Hyunggyu Lee

2006-01-01

196

A phenomenological model for pre-stressed piezoelectric ceramic stack actuators  

NASA Astrophysics Data System (ADS)

In order to characterize the hysteretic characteristics between the output displacement and applied voltage of pre-stressed piezoelectric ceramic stack actuators (PCSAs), this paper considers that a linear force and a hysteretic force will be generated by a linear extension and a hysteretic extension, respectively, due to the applied voltage to a pre-stressed PCSA and the total force will result in the forced vibration of the single-degree-of-freedom (DOF) system composed of the mass of the pre-stressed PCSA and the equivalent spring and damper of the pre-stressed mechanism, which lets the PCSA be pre-stressed to endure enough tension. On this basis, the phenomenological model to characterize the hysteretic behavior of the pre-stressed PCSA is put forward by using the Bouc-Wen hysteresis operator to model the hysteretic extension. The parameter identification method in a least-squares sense is established by identifying the parameters for the linear and hysteretic components separately with the step and periodic responses of the pre-stressed PCSA, respectively. The performance of the proposed phenomenological model with the corresponding parameter identification method is experimentally verified by the established experimental set-up. The research results show that the phenomenological model for the pre-stressed PCSA with the corresponding parameter identification method can accurately portray the hysteretic characteristics of the pre-stressed PCSA. In addition, the phenomenological model for PCSAs can be deduced from the phenomenological model for pre-stressed PCSAs by removing the terms related to the pre-stressed mechanisms.

Wang, D. H.; Zhu, W.

2011-03-01

197

Piezoelectric ceramic-polymer composites for weigh-in-motion sensors  

Microsoft Academic Search

Piezoelectric materials produce a voltage proportional to an applied pressure. Using this phenomenon, piezoelectric polymer sensors are already being used for collecting traffic data including weight-in-motion, measuring speeds and counting axles. The polymer sensors are usually in the form of a long tape or cable embedded within long blocks of elastomeric material. These sensor assemblies are then installed into grooves,

Rajesh K. Panda; Patrick J. Szary; Ali Maher; Ahmad Safari

1998-01-01

198

Influence of zirconium substitution on dielectric, ferroelectric and field-induced strain behaviors of lead-free 0.99[Bi1/2(Na0.82K0.18)1/2(Ti1- x Zr x )O3]-0.01LiSbO3 ceramics  

NASA Astrophysics Data System (ADS)

The Crystal structure, dielectric, ferroelectric and field-induced strain behaviors of lead-free 0.99[Bi1/2(Na0.82K0.18)1/2(Ti1- x Zr x )O3]-0.01LiSbO3 (BNKTZ-LS) ceramics were investigated in the composition range x = 0 - 0.040. XRD patterns revealed the formation of a pure perovskite phase with no apparent structural phase transition. The temperature-dependent dielectric peaks of the BNKTZ-LS ceramics broadened and the ferroelectric polarizations decreased with increasing Zr concentration. Ferroelectric and bipolar field induced-strain curves indicated a disruption of ferroelectric order upon Zr addition into the BNKT-LS ceramics. This destabilization of the ferroelectric order was accompanied by an enhanced field-induced strain. A high field-induced strain ( S = 0.30%) with a normalized strain ( d*33 = S max / E max = 500 pm/V) was observed at an applied electric field of 6 kV/mm at x = 0.020.

Zaman, A.; Iqbal, Y.; Hussain, A.; Ryu, G. H.; Song, T. K.; Kim, M. H.; Kim, W. J.

2012-09-01

199

HDPUG's Design for Lead-Free Solder Joint Reliability of High-Density Packages  

Microsoft Academic Search

The lead-free solder-joint reliability of the high-density packages, 256-pin PBGA (plastic ball grid array), 388-pin PBGA, and 1657-pin CCGA (ceramic column grid array), on PCB (printed circuit board) subjected to temperature cycling is investigated. Emphasis is placed on the determination of the creep responses (e.g., stress, strain, and strain energy density) of the lead-free solder joints of these packages. The

John Lau; Walter Dauksher; Joe Smetana; Dongkai Shangguan; Irv Menis; Dave Love; Bob Sullivan

200

Studies on lead-free multiferroic magnetoelectric composites  

NASA Astrophysics Data System (ADS)

Lead-free multiferroic magnetoelectric composites consisting of ferrimagnetic Ni0.93Co0.02Mn0.05Fe1.95O4 (NMF) and ferroelectric Na0.5Bi0.5TiO3 (NBT) phases were synthesized by the solid-state sintering method. The presence of constituent phases in composites was confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). A systematic study of dc conductivity as a function of temperature (RT -450 C) revealed that the conduction is due to small polarons. The effect of constituent phase variation on the dielectric constant and piezoelectric strength (d33) was examined. The composites exhibited typical magnetic hysteresis (M-H) loops at room temperature. Furthermore, magnetoelectric (ME) output was evaluated as a function of applied magnetic field, which is a product property of the constituent phases. The compound 50% NMF-50%NBT is a new lead-free magnetoelectric composite with 155 ?V/cm ME output, which may have potential applications.

Babu, S. Narendra; Srinivas, K.; Bhimasankaram, T.

2009-11-01

201

Plate-like structure health monitoring based on ultrasonic guided wave technology by using bonded piezoelectric ceramic wafers  

NASA Astrophysics Data System (ADS)

Piezoelectric ceramic wafers are applied for the excitation and detection of ultrasonic guided waves to determine the health state of plate-like structures. Two PZT wafers, whose diameter is 11mm and thickness is 0.4mm respectively, are bonded permanently on the surface of a 1mm thick aluminum plate. One of these wafers is actuated by sinusoidal tone burst at various frequencies ranging from 100kHz to 500kHz, the other one is used as a receiver for acquiring ultrasonic guided wave signals. According to the amplitudes and shapes of these received signals, guided wave modes and their proper frequency range by using these wafers are determined. For the improvement of the signal-to-noise ratio, the Daubechies wavelet of order 40 is used for signal denoising as the mother wavelet. Furthermore, the detection of an artificial cylindrical through-hole defect is achieved by using S0 at 300kHz. Experimental results show that it is feasible and effective to detect defects in plate-like structures based on ultrasonic guided wave technology by using bonded piezoelectric ceramic wafers.

Liu, Zenghua; Zhao, Jichen; He, Cunfu; Wu, Bin

2008-11-01

202

Piezoelectric activity of relaxor-PbTiO(3) based single crystals and polycrystalline ceramics at cryogenic temperatures: Intrinsic and extrinsic contributions.  

PubMed

The piezoelectric activity in [001] poled Pb(In(12)Nb(12))O(3)-Pb(Mg(13)Nb(23))O(3)-PbTiO(3) crystals was investigated as a function of composition and temperature. The level of intrinsic andor extrinsic contribution to the total piezoelectric activity was analyzed using Rayleigh method. The results revealed that though 95% of the observed piezoelectric activity in rhombohedral crystals was intrinsic (lattice), the properties decreased significantly with decreasing temperature. At -150 degrees C, the piezoelectric response decreased by 40%-55% for the compositions close to a morphotropic phase boundary (rhombohedral-monoclinic or monoclinic-tetragonal), while decreasing only 20%-30% for the compositions in the rhombohedral region. The piezoelectric properties of Pb(Mg(13)Nb(23))O(3)-PbTiO(3) polycrystalline ceramics were found to decrease by 75%, showing both intrinsic and extrinsic contributions play important role in the reduction in piezoelectricity at cryogenic temperatures for ceramics. PMID:20531980

Li, Fei; Zhang, Shujun; Xu, Zhuo; Wei, Xiaoyong; Luo, Jun; Shrout, Thomas R

2010-05-13

203

High Tc lead-free BaTiO3-(Bi1/2Na1/2)TiO3 positive temperature coefficient of resistivity ceramics with electrically heterogeneous structure  

NASA Astrophysics Data System (ADS)

A distinct positive temperature coefficient of resistivity effect has been observed in BaTiO3-(Bi1/2Na1/2)TiO3 (BT-BNT) ceramics sintered in a N2 flow with low O2 concentration. With the addition of BNT, the samples exhibit resistivity jumps of ~103-105 starting at ~190-210 C. X-ray diffraction results indicate that the BNT phase and BT phase formed a solid solution during sintering. An electrically heterogeneous structure, consisting of the grain interiors, outer grain shells, and grain boundaries, is revealed by the complex impedance analyses. The observed dc resistivity jump is attributed to the rapid resistivity rise in both grain boundaries and grain shells.

Xiang, Ping-Hua; Takeda, Hiroaki; Shiosaki, Tadashi

2007-10-01

204

Structural characteristics of Mg-doped (1-x)(K0.5Na0.5)NbO3-xLiSbO3 lead-free ceramics as revealed by Raman spectroscopy  

NASA Astrophysics Data System (ADS)

This paper presents a Raman spectroscopic study of compositional-change-induced structure variation and of the related mechanism of Mg doping in LiSbO3 (LS)-modified (K0.5Na0.5)NbO3 (KNN) ceramics. With increasing LS content from 0 to 0.06, a discontinuous shift towards higher wavenumbers was found for the band position of the A1g(v1) stretching mode of KNN, accompanied by a clearly nonlinear broadening of this band and a decrease in its intensity. Such morphological changes in the Raman spectrum result from two factors: (i) changes in polarizability/binding strength of the O-Nb-O vibration upon incorporation of Li ions in the KNN perovskitic structure and (ii) a polymorphic phase transition (PPT) from orthorhombic to tetragonal (O ? T) phase at x > 0.04. Upon increasing the amount, w, of Mg dopant incorporated into the (1-x)KNN-xLS ceramic structure, the intensity of the Raman bands are enhanced, while the peak position and the full width at half maximum of the A1g(v1) mode was found to experience a clear dependence on both w and x. Raman characterization revealed that the mechanism of Mg doping is strongly correlated with the concentration of Li in the perovskite structure: Mg2+ ions will preferentially replace Li+ ions for low Mg doping while replace K/Na ions for higher doping of Mg. The PPT O ? T was also found to be altered by the introduction of Mg and the critical value of LS concentration, xO-T, for incipient O ? T transition in the KNN-xLS-wMT system was strongly dependent on Mg content, with xO ? T being roughly equal to 0.04 + 2w, for the case of dilute Mg alloying.

Zhu, W. L.; Zhu, J. L.; Meng, Y.; Wang, M. S.; Zhu, B.; Zhu, X. H.; Zhu, J. G.; Xiao, D. Q.; Pezzotti, G.

2011-12-01

205

Roadmap of Lead-free Soldering  

Microsoft Academic Search

In this presentation is profiled in short form roadmap of Lead-free soldering process, which has a general character and sums the most important parameters and factors that concern achievements of good solder joint quality. This course is involved in the 5th semester of the Bachelor study program as well in extended form in Master Study program at Brno University of

Ivan Szendiuch

2007-01-01

206

Interface failure in lead free solder joints  

Microsoft Academic Search

The phenomenon of interface failure in lead free solder joints was explored using solder joint array tensile testing. The effects of pad metallization, solder alloy, reflow conditions, and post reflow thermal aging were quantified. The joint strength ranged from 5 to 115MPa. The joint ductility dropped to zero in some cases. The interface microstructure and failure mode were characterized for

Robert Darveaux; Corey Reichman; Nokibul Islam

2006-01-01

207

Dielectric and piezoelectric properties of Bi2O3 added (Pb,Ca,Sr)(Ti,Mn,Sb)O3 ceramics sintered at low temperature  

NASA Astrophysics Data System (ADS)

In this study, in order to develop low temperature sintering ceramics for a thickness mode multilayer piezoelectric transformer, (Pb,Ca,Sr)(Ti,Mn,Sb)O3 ceramics were fabricated using Na2CO3, Li2CO3, MnO2, and Bi2O3 as sintering aids at 870, 900, and 930 C. Their respective dielectric and piezoelectric properties were investigated according to the amount of Bi2O3 addition. At the sintering temperature of 900 C, the optimum value was shown for the density of 6.94 g/cm3, thickness vibration mode electromechanical coupling factor (henceforth, kt) of 0.497, thickness vibration mode mechanical quality factor (henceforth, Qmt) of 3162, and dielectric constant (henceforth, ?r) of 209 for thickness mode multilayer piezoelectric transformer application.

Kim, Dohyung; Yoo, Juhyun; Kim, Insung; Song, Jaesung

2009-03-01

208

Piezoelectric and dielectric properties of Pb(Ni13\\/Nb23\\/)O3 Pb(Mn13\\/Nb23\\/)O3Pb(Zr,Ti)O3 ceramics for piezoelectric transformer  

Microsoft Academic Search

In this study, the structural, dielectric and piezoelectric properties of Pb[(Ni13\\/Nb23\\/)x - (Mn13\\/Nb23\\/)0.09-x (Zr0.505Ti0.495)0.91]O3 (x = 0, 0.01, 0.02, 0.03, 0.04, 0.05) system ceramics were investigated to develop the composition for piezoelectric transformers. All the specimens were sintered at 1250C and their physical properties were measured, and the results are as follows; With increasing PNN substitution for PMN-PZT system, the

S. M. Hwang; J. H. Yoo; L. H. Hwang; J. I. Hong; S. R. Ryu; S. I. Lee; M. S. Lee

2002-01-01

209

Dielectric and Piezoelectric Properties of Low-Temperature-Sintering Pb(Mg1\\/2W1\\/2)O3Pb(Ni1\\/3Nb2\\/3)O3Pb(Zr,Ti)O3 Ceramics for Multilayer Piezoelectric Actuator  

Microsoft Academic Search

In this study, in order to develop low-temperature-sintering ceramics for a multilayer piezoelectric actuator, Pb(Mg1\\/2W1\\/2)O3-Pb(Ni1\\/3Nb2\\/3)O3-Pb(Zr,Ti)O3 (PMW-PNN-PZT) ceramics were fabricated using Li2CO3 and CaCO3 as sintering aids and their dielectric and piezoelectric properties were investigated in relation to the amount of Bi substitution. Piezoelectric actuators require both a high piezoelectric constant (d33) and a high electromechanical coupling factor (kp). Accordingly, in

Juhyun Yoo; Kyungjin Yoo; Hyunseok Lee; Sangho Lee; Kwanghyun Chung; Hyeunggyu Lee; Hyungwon Kang

2005-01-01

210

Electromechanical properties of A-site (LiCe)-modified sodium bismuth titanate (Na{sub 0.5}Bi{sub 4.5}Ti{sub 4}O{sub 15}) piezoelectric ceramics at elevated temperature  

SciTech Connect

The Aurivillius-type bismuth layer-structured (NaBi){sub 0.46}(LiCe){sub 0.04}Bi{sub 4}Ti{sub 4}O{sub 15} (NBT-LiCe) piezoelectric ceramics were synthesized using conventional solid-state processing. Phase analysis was performed by x-ray diffraction and microstructural morphology was assessed by scanning electron microscopy. The dielectric, piezoelectric, ferroelectric, and electromechanical properties of NBT-LiCe ceramics were investigated. The piezoelectric activities were found to be significantly enhanced compared to NBT ceramics, which can be attributed to the lattice distortion and the presence of bismuth vacancies. The dielectric and electromechanical properties of NBT-LiCe ceramics at elevated temperature were investigated in detail. The excellent piezoelectric, dielectric, and electromechanical properties, coupled with high Curie temperature (T{sub c}=660 deg. C), demonstrated that the NBT-LiCe ceramics are the promising candidates for high temperature applications.

Wang Chunming; Wang Jinfeng [School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100 (China); Zhang Shujun; Shrout, Thomas R. [Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

2009-05-01

211

Electromechanical properties of A-site (LiCe)-modified sodium bismuth titanate (Na0.5Bi4.5Ti4O15) piezoelectric ceramics at elevated temperature  

NASA Astrophysics Data System (ADS)

The Aurivillius-type bismuth layer-structured (NaBi)0.46(LiCe)0.04Bi4Ti4O15 (NBT-LiCe) piezoelectric ceramics were synthesized using conventional solid-state processing. Phase analysis was performed by x-ray diffraction and microstructural morphology was assessed by scanning electron microscopy. The dielectric, piezoelectric, ferroelectric, and electromechanical properties of NBT-LiCe ceramics were investigated. The piezoelectric activities were found to be significantly enhanced compared to NBT ceramics, which can be attributed to the lattice distortion and the presence of bismuth vacancies. The dielectric and electromechanical properties of NBT-LiCe ceramics at elevated temperature were investigated in detail. The excellent piezoelectric, dielectric, and electromechanical properties, coupled with high Curie temperature (Tc=660 C), demonstrated that the NBT-LiCe ceramics are the promising candidates for high temperature applications.

Wang, Chun-Ming; Wang, Jin-Feng; Zhang, Shujun; Shrout, Thomas R.

2009-05-01

212

THE PROLIFERATION OF LEAD-FREE ALLOYS  

Microsoft Academic Search

The advent of the EU's RoHS law has encouraged a significant amount of research to find an alloy, for electronic assembly, that will satisfy RoHS's lead-free requirement and have optimum process ability and field reliability. The resulting research, much of it lead by iNEMI, resulted in the near eutectic tin-silver-copper alloy SAC387 (Sn95.5Ag3.8Cu 0.7) as an initial favorite to fill

Eric Bastow; Timothy Jensen

2009-01-01

213

Electrochemical migration of lead free solder joints  

Microsoft Academic Search

Electrochemical migration (ECM) tests on lead bearing and lead free solder joints on Cu lamination on FR-4 board were conducted\\u000a by applying constant voltage. This paper first studied the ECM of the soldered joints under distilled water after removing\\u000a the fluxes. In addition, conditions under high temperature and high humidity were also set up to investigate the changes of\\u000a the

D. Q. Yu; W. Jillek; E. Schmitt

2006-01-01

214

Lead free tin based solder composition  

US Patent & Trademark Office Database

Lead-free solder alloys based on a Sn--Ag--Mg system are disclosed. The alloy compositions have a melting temperature close to 183.degree. C. and a similar surface tension to that of Sn--Pb solder, and can thus be a readily substituted for conventional Sn--Pb solders. P may be added to the alloy compositions to reduce its tendency of oxidation.

2004-11-30

215

Reduction of the piezoelectric performance in lead-free (1-x)Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)TiO3 piezoceramics under uniaxial compressive stress  

NASA Astrophysics Data System (ADS)

The effect of a uniaxial compressive stress on the properties of BZT-BCT samples across the morphotropic phase boundary (MPB) is investigated using direct piezoelectric coefficient measurements. In contrast to many lead zirconate titanate compositions, the piezoelectric coefficient decreases monotonically with increasing stress and does not show an initial increase or plateau. Electrically softer rhombohedral and MPB compositions are found to be more susceptible to a decrease in piezoelectric coefficient under an increasing pre-stress than tetragonal compositions. Depoling due to ferroelastic domain switching alone, as observed by x-ray diffraction, does not explain this reduction, but instead a decreasing domain wall density is proposed to be responsible for reduced piezoelectric coefficients under increasing compressive stress. The relaxation of the piezoelectric response after complete unloading supports this proposed mechanism.

Ehmke, Matthias C.; Daniels, John; Glaum, Julia; Hoffman, Mark; Blendell, John E.; Bowman, Keith J.

2012-12-01

216

Accurate Characterization And Modeling of Piezoelectric And Electrostrictive Ceramics And Single Crystals  

NASA Astrophysics Data System (ADS)

The continuing need for large actuation and a continually increasing variety of applications has seen the use of piezoelectric materials under a growing range of conditions. These include large applied AC fields, DC bias fields, applied stresses as well as a wider range of frequencies and temperatures. Under these conditions the behaviour of the materials becomes non-linear and is not described well by the small signal parameters supplied by material manufacturers. It is therefore necessary to know and understand the behaviour of piezoelectric materials under these conditions. This presentation reviews the work that has been carried out at the Laboratory for Ferroelectric Materials in the Royal Military College of Canada where we have been studying the non-linear properties of piezoelectric and electrostrictive materials by observing their strain, dielectric and elastic behaviour under the various conditions mentioned above.

Mukherjee, Binu

2008-07-01

217

Piezoelectric properties of nonstoichiometric Sr1-xBi2+2x/3Ta2O9 ceramics  

NASA Astrophysics Data System (ADS)

The effect of poling on the structural, dielectric, and piezoelectric properties has been investigated for sol-gel-derived strontium bismuth tantalate (SBT) [Sr1-xBi2+2x/3Ta2O9] ceramics with x=0.0,0.15,0.30,0.45. The dielectric and ferroelectric properties are found to improve with increase in x up to 0.3. Beyond x>0.3 the properties are found to degrade due to the limited solid solubility and the presence of a mixed phase of bismuth tantalate (BiTaO4) is detected with x=0.45. Poling treatment reduces the dielectric dispersion and dielectric loss in the frequency range (0.1-100 kHz). The resonance and antiresonance frequencies increase with increase in x (x=0-0.30), and the corresponding minimum impedance decreases. The measured coupling coefficients (kp) are small (0.0967-0.1) for x=0-0.30, and the electromechanical quality factor (Qm=915) is a maximum for the Sr0.7Bi2.2Ta2O9 composition (x=0.30). The estimated piezoelectric charge coefficient (d31) and piezoelectric voltage coefficient (g31) are 5.2 pC/N and 5.810-3 V m/N, respectively. The positive values of d31 and g31 and the low dielectric permittivity of SBT yield a high value for the hydrostatic coefficients, despite the low charge coefficient of d33=24 pC/N. The maximum values of charge coefficient (dh=34 pC/N) and voltage coefficient (gh=3910-3 V m/N) are obtained for Sr0.7Bi2.2Ta2O9 composition, and the estimated hydrostatic figure of merit (dhgh10-15=1215 m2/N) is high.

Jain, Rajni; Chauhan, Arun Kumar Singh; Gupta, Vinay; Sreenivas, K.

2005-06-01

218

First-Principles Calculation of Lead-Free Perovskite SnTiO3  

NASA Astrophysics Data System (ADS)

The phonon spectra, band structure and density of states of cubic perovskite SnTiO3 were investigated using first-principles density functional theory (DFT) computation. The potential energy curves of cations displacement and the formation energy of Sn substitution to B-site were calculated to estimate the structure stability. The results indicate that perovskite SnTiO3 is a promising ferroelectric end member for lead-free piezoelectric materials and applications.

Ye, Hongjun; Zhang, Ruizhi; Wang, Dawei; Cui, Yu; Wei, Jie; Wang, Chunlei; Xu, Zhuo; Qu, Shaobo; Wei, Xiaoyong

2013-09-01

219

Fabrication of Lead-Free Ferroelectric Microstructures by Electron-Beam-Induced Patterning Process  

Microsoft Academic Search

300 nm to 50 ?m-sized circular dots of Bi4Ti3O12 (BIT) and BaTiO3 (BT), lead-free ferroelectric materials, micropatterns were fabricated by electron-beam-induced micropatterning process using scanning electron microscope (SEM)-based electron beam lithography system. Obtained micro dots were characterized using optical microscope and atomic force microscope. The piezoelectric property of the BIT and BT micro dots were examined by piezoresponse scanning force

Tadashi Fujii; Sugure Hirabayashi; Masatoshi Adachi

2009-01-01

220

Acoustical Imaging Using a Leaky Wave Transducer Composed of a Piezoelectric Ceramic Plate and an Acryl Plate  

NASA Astrophysics Data System (ADS)

An interdigital transducer (IDT) for leaky waves in a layered substrate composed of a piezoelectric ceramic thin plate and an acryl plate is incorporated into a C-mode acoustical imaging system. The transducer performance in the layered structure is described from the viewpoint of ultrasound radiation at an interface between an acryl plate and a water layer. The leaky wave transducer has frequency-dependent radiation angles, corresponding to the leaky wave velocity, under multiple operation modes. The bulk wave direction in a test sample via the longitudinal wave in the water layer is easily controlled by frequency change. A reflection type C-mode acoustical imaging system is successfully demonstrated for nondestructive testing.

Toda, Kohji; Motegi, Kenji

1995-05-01

221

Research on the displacement function and equivalent circuit of circular flexural vibration mode piezoelectric ceramic composite transducers.  

PubMed

Flexural vibration mode piezoelectric ceramic transducers can be used in many application fields because of their ability to develop large displacement at low levels of electrical excitation, or conversely, to generate high output from sources of low mechanical impedance. Many flexural transducers are very thin, and their behavior can be analyzed and predicted accurately by the current theory based on thin-plate assumptions. However, for those flexural transducers with moderate thickness, the thin-plate assumptions are no longer valid. To analyze and predict the behaviors of the flexural transducers with moderate thickness, we must establish a new theory. In this paper, by introducing Mindlin's assumptions and theory, the displacement function and equivalent circuit for circular flexural composite transducers with moderate thickness are derived. Through the displacement function and the equivalent circuit, the vibration characteristics and the electrical impedance of circular flexural composite transducers with moderate thickness can be predicted directly. PMID:23287927

Yihua, Huang; Wenjin, Huang

2013-01-01

222

Effects of ZnO\\/Li 2O codoping on microstructure and piezoelectric properties of low-temperature sintered PMNPNNPZT ceramics  

Microsoft Academic Search

Pb(Mg1\\/3Nb2\\/3)O3Pb(Ni1\\/3Nb2\\/3)O3Pb(Zr1\\/2Ti1\\/2)O3 (designated as PMNT) piezoelectric ceramics codoping with Zn2+\\/Li+ were prepared and the effects of ZnO\\/Li2O (Z\\/L) additive on microstructure, piezoelectric and dielectric properties were investigated. The results show that the pure perovskite phase is formed and the phase structure changes from tetragonal to rhombohedral with different Z\\/L weight ratios. The Curie temperature Tc, dielectric constant ?, electromechanical coupling factor

Gao Feng; Hong Rongzi; Liu Jiaji; Li Zhen; Tian Chang-sheng

2009-01-01

223

Piezoelectric ceramic bimorph coupled to thin metal plate as cooling fan for electronic devices  

Microsoft Academic Search

Several types of piezoelectric fans for cooling electronic devices were constructed and tested at 60 Hz, 110 V and 220 V, respectively. The aim of the work is to investigate the possibility of replacing the rotary type of fan in some noise-sensitive electronic devices. Different vibrating metal plates were tested and analyzed theoretically. It is found that the resonant frequency

Ju Hyun Yoo; Jae Il Hong; Wenwn Cao

2000-01-01

224

Simple model for piezoelectric ceramic\\/polymer 1-3 composites used in ultrasonic transducer applications  

Microsoft Academic Search

A theoretical model is presented for combining parameters of 1-3 ultrasonic composite materials in order to predict ultrasonic characteristics such as velocity, acoustic impedance, electromechanical coupling factor, and piezoelectric coefficients. Hence, the model allows the estimation of resonance frequencies of 1-3 composite transducers. This model has been extended to cover more material parameters, and they are compared to experimental results

H. L. W. Chan; JOSEPH UNSWORTH

1989-01-01

225

Lead-free piezoceramics with giant strain in the system Bi{sub 0.5}Na{sub 0.5}TiO{sub 3}-BaTiO{sub 3}-K{sub 0.5}Na{sub 0.5}NbO{sub 3}. I. Structure and room temperature properties  

SciTech Connect

Lead-free piezoelectric ceramics (1-x-y)Bi{sub 0.5}Na{sub 0.5}TiO{sub 3}-xBaTiO{sub 3}-yK{sub 0.5}Na{sub 0.5}NbO{sub 3} (0.05{<=}x{<=}0.07 and 0.01{<=}y{<=}0.03), have been synthesized by a conventional solid state sintering method. The room temperature ferroelectric and piezoelectric properties of these ceramics were studied. Based on the measured properties, the ceramics were categorized into two groups: group I compositions having dominant ferroelectric order and group II compositions displaying mixed ferroelectric and antiferroelectric properties at room temperature. A composition from group II near the boundary between these two groups exhibited a strain as large as {approx}0.45% at an electric field of 8 kV/mm. Polarization in this composition was not stable in that the piezoelectric coefficient d{sub 33} at zero electric field was only about 30 pm/V. The converse piezoelectric response becomes weaker when the composition deviated from the boundary between the groups toward either the ferroelectric or antiferroelectric compositions. These results were rationalized based on a field induced antiferroelectric-ferroelectric phase transition.

Zhang, S.-T.; Kounga, Alain Brice; Aulbach, Emil; Granzow, Torsten; Jo, Wook; Kleebe, Hans-Joachim; Roedel, Juergen [Institute of Materials Science, Technische Universitaet Darmstadt, Petersenstr. 23, 64287 Darmstadt (Germany)

2008-02-01

226

Effects of rare earth metal substituents on the high power piezoelectric properties in lead zirconate titanate-lead (antimony,manganese)O(3) ceramics  

NASA Astrophysics Data System (ADS)

Improved piezoelectric materials with higher vibrational velocities are needed to meet the demands of advanced high power electromechanical applications. In this thesis, the effects of the rare earth (RE) metal substituents on the vibrational velocity, the piezoelectric properties and polarization behavior of Pb(Zr,Ti)O3-Pb(Sb,Mn)O3 ceramics have been investigated. Under high drive levels, the mechanical quality factor and the vibrational velocity were both significantly improved by RE substitution. For a longitudinal vibrator, driven under the d31 mode, root mean square value (rms value) of vibration velocity as high as 0.9 m/s under an electric field of 10 kV/m (rms value) has been found for Yb-substituted specimens, which is 1.5 times higher than that of base Pb(Zr,Ti)O3-Pb(Sb,Mn)O 3 ceramics. For most of rare earth substituents investigated in this system, regardless of the species ionic radii, the piezoelectric properties were observed to have combinative "hard" and "soft" characteristics. "Hard" piezoelectrics have higher Qm values, but lower k31 values. On the other hand, "soft" piezoelectrics have lower Qm values, but higher k31 values. The increased mechanical quality factor Qm (typical of "hard" piezoelectrics) and increased electromechanical coupling coefficient k31 (typical of "soft" ones) were both achieved by RE substitution. With increasing rare earth substituent ionic size, there was no absolute proportional relationship between k31/Qm and dopant ionic size observed. Polarization-electric field (P-E) measurements revealed a significant relaxational polarization similar to a "soft" piezoelectric, in addition to an internal dipolar field similar to a "hard" piezoelectric. A possible explanation for the combinative "hardening" and "softening" effects is the coexistence of randomly quenched and mobile defects. The time dependences after poling of the mechanical quality factor Q m, electromechanical coupling coefficient k31 and dielectric constant K have been investigated for both "soft" and "hard" lead zirconate titanate (PZT) ceramics. A significant increase of Qm with time was observed for "hard" PZTs, however "soft" ones did not exhibit any changes during the same time period. The aging rate after poling was found to be related to the degree of "hard" characteristics. Polarization versus electric field (P-E) measurements of "hard" PZTs revealed the development of a shift of the response along the E axis with time. It is believed that an internal dipolar field develops with time, due to a reorientation of defect dipoles along the direction of spontaneous polarization through oxygen diffusion. (Abstract shortened by UMI.)

Gao, Yongkang

227

A three-phase magnetoelectric composite of piezoelectric ceramics, rare-earth iron alloys, and polymer  

NASA Astrophysics Data System (ADS)

A class of multiferroic, three-phase particulate composites of Tb-Dy-Fe alloy, lead-zirconate-titanate (PZT), and polymer are investigated, in which a small volume fraction f of Tb-Dy-Fe alloy particles are dispersed in a PZT/polymer mixture. The measured dielectric, piezoelectric, and magnetoelectric properties demonstrate that a percolation transition occurs at f~0.12 in the composites. When f is low (e.g., f<0.07), the composites exhibit piezoelectric and increasing magnetoelectric response. In the critical f range of 0.07

Nan, C.-W.; Liu, L.; Cai, N.; Zhai, J.; Ye, Y.; Lin, Y. H.; Dong, L. J.; Xiong, C. X.

2002-11-01

228

Inharmonic Overtone Spurious Mode Suppression by Partial Mass-Loading onto the Electrode for Energy-Trapped-Type Thickness-Extensional-Mode Piezoelectric Ceramic Resonators  

Microsoft Academic Search

Experimental studies have been performed on the suppression of the inharmonic overtone responses for realizing piezoelectric ceramic resonators with low resonance impedance compatible with a wide-area electrode(>phi15lambda). The circumferential mass-loading onto the electrode is effective for the fabrication of an oscillator with a low oscillation startup voltage, without any jump to spurious frequencies. In addition, this technique results in a

Yoshinari Yamashita; Yasunobu Oikawa; Masanobu Sugimoto

1998-01-01

229

Unusual pyroelectric and piezoelectric properties of fresnoite (Ba2TiSi2O8) single crystal and polar glass-ceramics  

Microsoft Academic Search

The dielectric, piezoelectric and pyroelectric properties of fresnoite (Ba2TiSi2Os) single crystal and polar glass-ceramics were studied in the temperature range - 150 to 200C. The sign of pyroelectric coefficient is positive at room temperature and becomes negative at 190C. The dielectric constant, pyroelectric coefficient and planar coupling coefficient show a maximum value at 160C and the frequency constant shows a

A. Halliyal; A. S. Bhalla; S. A. Markgraf; L. E. Cross; R. E. Newnham

1985-01-01

230

Dielectric, piezoelectric and pyroelectric properties of Sr 2 TiSi 2 O 8 polar glass-ceramic: A new polar material  

Microsoft Academic Search

Polar Sr2TiSi2O8 glass-ceramics were prepared by recrystallizing glasses in a steep temperature gradient. The dielectric, piezoelectric and pyroelectric properties were studied as a function of temperature in the temperature range -150 to 200 C. The sign of the pyroelectric coefficient is positive at room temperature and is attributed to the dominance of the secondary pyroelectric effect over the primary effect.

A. Halliyal; A. S. Bhalla; L. E. Cross; R. E. Newnham

1985-01-01

231

Fabrication of Pb(Nb,Ni)O3Pb(Zr,Ti)O3 Piezoelectric Ceramic Fibers by Extrusion of a Sol-Powder Mixture  

Microsoft Academic Search

A study on the fabrication of Pb(Nb,Ni)O3-Pb(Zr,Ti)O3 (PNN-PZT) piezoelectric ceramic fibers by extrusion of a powder-sol mixture is presented. The process using extrusion of a powder-sol mixture was first applied to the fabrication of PZT fibers and its advantages were discussed in the former study. In this study, the process is applied to the fabrication of PNN-PZT fibers, and the

Jinhao Qiu; Junji Tani; Naoki Yanada; Yoshimasa Kobayashi; Hirofumi Takahashi

2004-01-01

232

Investigation of high Curie temperature (1-x)BiSc1-yFeyO3-xPbTiO3 piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

Ceramics around the morphotropic phase boundary (MPB) in the (1-x)BiSc1-yFeyO3-xPbTiO3 solid solution were fabricated. For y=0.5, ceramics were single phase, and piezoelectric coefficients (d33) and electromechanical coupling coefficients (kp) for MPB compositions were 300 pC/N and 0.49, respectively; a level of piezoelectric activity similar to that of hard, lead zirconate titanate compositions but with TC~60 C higher at ~440 C. For ceramics with y>=0.7, dielectric measurements in combination with diffraction contrast transmission electron microscopy revealed the existence of two ferroelectric phases for most PbTiO3 contents studied. The presence of two ferroelectric phases was associated with a decrease in piezoelectric activity and although raw materials costs for y=0.7 and 0.8 with respect to y=0 were significantly lower (less Sc2O3) and TC greater (~500 C), d33 (~100 pC/N) and kp (0.18) were too low to be commercially useful for actuator applications.

Sterianou, I.; Sinclair, D. C.; Reaney, I. M.; Comyn, T. P.; Bell, A. J.

2009-10-01

233

Development of the Lead Free Soldering Process for Portable Applications  

Microsoft Academic Search

In the frame of European Union founded IMECAT-project the lead free soldering process for portable electronic devices has been developed. For the evaluation suppose a special PCB testboard has been designed. The lead free components which are selected to this testboard are commonly used in portable applications. The smallest components are 0201-type lead free resistors which are assemblied in groups

Jarmo Mttnen; Pori Greta Maakannas

234

Incorporation of piezoelectric Pb(Zr,Ti)O3 fibers into ceramic/polymer composites  

NASA Astrophysics Data System (ADS)

The processing of Pb(Zr,Ti)O3, or PZT, fiber and fiber/polymer composites for transducer applications is discussed. Green PZT fibers, 80 to 100 micrometers in diameter, were formed at Advanced Cerametrics, Inc., using the Viscous Suspension Spinning Process (VSSP). In this process, fine PZT powder is intimately mixed with polymer precursor by high shear mixing. The powder and precursor mixture is spun through a spinneret into a coagulation bath to form fibers. The fibers are washed, dried, and collected on a spool. Yarns containing between 10 and 500 individual fibers were collimated by applying a polymeric sizing to the yarns, and passing the yarns through sizing dies. Yarn bundle tightness and flexibility were controlled by the sizing chemistry. Continuous green yarns were cut to short lengths, or woven in different architectures to create composites with novel microstructures. The short yarns were fired to product PZT straight rods for `pick and place' piezoelectric composites. The woven structures were heat treated and backfilled with polymer to create composites with 1-3, 2-3, and 3-3 connectivity. After heat treatment, the diameter of the individual PZT fibers was 10 to 20 micrometers . Electromechanical characteristics of a number of composites were determined, and will be reported. The PZT VSSP fibers can be used to form fine-scale, large area piezoelectric fiber/polymer composites for use in hydrophones, transducers for medical ultrasonic imaging and non-destructive evaluation, and as sensors and actuators in vibration and noise control.

Safari, Ahmad; Janas, Victor; Jadidian, Bahram; French, Jonathan; Weitz, Greg; Luke, John; Cass, Bud

1996-05-01

235

Machining piezoelectric (PZT) ceramics using an electrochemical spark machining (ECSM) process  

Microsoft Academic Search

Machining of advanced engineering materials such as composites and ceramics is important but it is very difficult and uneconomical to do so by conventional methods of machining. A need for new techniques for machining these advanced engineering materials cannot be over-emphasized. In this study, the authors have attempted to explore the feasibility of using an electrochemical spark machining (ECSM) process

Y. P. Singh; Vijay K. Jain; Prashant Kumar; D. C. Agrawal

1996-01-01

236

Passive Vibration Damping Materials: Piezoelectric Ceramic Composites for Vibration Damping Applications.  

National Technical Information Service (NTIS)

The study to produce ultra-fine (less than 50 micrometers in diameter) lead zirconate titanate (PZT) ceramic fibers for passive damping application has been carried out under several aspects. Sol-gel chemistry was undertaken to produce stable spinnable so...

S. Yoshikawa

1994-01-01

237

The use of the ultrasonic compaction method for the PZT piezoelectric ceramics fabrication  

Microsoft Academic Search

The method of ultrasonic (US) compaction for the fabrication of Pb(ZrTi)O3 PZT piezoceramics was approved. The values of density, granularity, shrinkage of ceramic samples, sintered from the compacts compacted by traditional uniaxial pressing and by ultrasound action are compared. It is shown that US compaction contributes to sintering temperature lowering and to PZT piezoceramics granularity reduction

O. L. Khasanov; J. S. Lee; Yu. P. Pokholkov; V. M. Sokolov; E. S. Dvilis; M. S. Kim; B. G. An

1999-01-01

238

Effect of SHI irradiation on NBT-BT ceramics: Transformation of relaxor ferroelectric to ferroelectric nature  

NASA Astrophysics Data System (ADS)

The lead free NBT-BT ceramics prepared by conventional solid state reaction method were irradiated with 120 MeV Au9+ ions with different fluences. The structural, dielectric and piezoelectric studies were carried out before and after irradiation. The agglomeration and increase of grain size are observed in SEM analysis after the irradiation. The diffuse phase transition disappeared after high fluence of irradiation and the material becomes ferroelectric in nature. The piezoelectric properties were decreased due to the reduced stability of the ferroelectric domains after the irradiation.

Shanmuga Sundari, S.; Kumar, Binay; Asokan, K.; Dhanasekaran, R.

2013-01-01

239

Properties of Cerium Containing Lead Free Solder  

NASA Astrophysics Data System (ADS)

With increasing concerns of the intrinsic toxicity of lead (Pb) in electronics, a series of tin (Sn) based alloys involving silver (Ag) and copper (Cu) have been proposed as replacements for Pb-Sn solder and widely accepted by industry. However, they have a higher melting point and often exhibit poorer damage tolerance than Pb-Sn alloys. Recently, a new class of alloys with trace amount of rare-earth (RE) elements has been discovered and investigated. In previous work from Prof. Chawla's group, it has been shown that cerium (Ce)-based Pb-free solder are less prone to oxidation and Sn whiskering, and exhibit desirable attributes of microstructural refinement and enhanced ductility relative to lanthanum (La)-based Sn-3.9Ag-0.7Cu (SAC) alloy. Although the formation of RESn3 was believed to be directly responsible for the enhanced ductility in RE-containing SAC solder by allowing microscopic voids to nucleate throughout the solder volume, this cavitation-based mechanism needs to be validated experimentally and numerically. Additionally, since the previous study has exhibited the realistic feasibility of Ce-based SAC lead-free solder alloy as a replacement to conventional SAC alloys, in this study, the proposed objective focuses on the in in-depth understanding of mechanism of enhanced ductility in Ce-based SAC alloy and possible issues associated with integration of this new class of solder into electronic industry, including: (a) study of long-term thermal and mechanical stability on industrial metallization, (b) examine the role of solder volume and wetting behavior of the new solder, relative to Sn-3.9Ag-0.7Cu alloys, (c) conduct experiments of new solder alloys in the form of mechanical shock and electromigration. The research of this new class alloys will be conducted in industrially relevant conditions, and the results would serve as the first step toward integration of these new, next generation solders into the industry.

Xie, Huxiao

240

Dielectric, ferroelectric and mechanical Properties of Microwave Sintered Bi based High temperature Piezoelectric Ceramics  

NASA Astrophysics Data System (ADS)

The sintering of advanced ceramics requires fast heating in order to avoid both grain growth and inter diffusion. In this context, the microwave sintering is a powerful method since it enables sintering in a short time. This paper reports the synthesis and characterization of Strontium Bismuth Titanate (SBTi) system. The material powder was prepared by solid state route and sintering was carried out by both conventional and microwave furnaces. Morphological, dielectric, ferroelectric and mechanical properties were studied for both samples. The dielectric constant and loss tangent of the conventional and microwave sintered samples have ranged between (185-195) & (0.005-0.007) and (195-220) & (0.004-0.006) respectively when measured at 1MHz frequency. The microwave sintering of the SBTi ceramics leads to higher densification (97% of the theoretical density), fine microstructure, and good mechanical and ferroelectric properties in much shorter duration of time compared to that of the conventional sintering process.

Angalakurthi, Rambabu; Raju, K. C. James

2011-10-01

241

The piezoelectric properties of low-temperature sintered PNN-PZT-based ceramics and their applications  

Microsoft Academic Search

0.25Pb(Ni1\\/3Nb2\\/3)O30. 75Pb(Zr0.52Ti0.48)O3 (PNN-PZT) piezoceramics, doped and undoped with BiFeO3 and Ba(Cu0.5W0.5)O3 oxides, were prepared by conventional mixed-oxide technique, using sintering temperature at 850C-950C. Microstructural and compositional analyses of these low-temperature sintered PNN-PZT-Based ceramics have been carried out using XRD and SEM. The effects of dopants on the sintering temperature and dielectric properties of the PNN-PZT ceramics have been investigated. In

Sheng-Yuan Chu; Cheng-Shung Hsieh

1999-01-01

242

Dielectric and piezoelectric properties of PNN-PZN-PZT ceramics for actuator application  

Microsoft Academic Search

In the fields of optics, precision machinery and semiconductor processing, microposition actuators are required for the control of position in the submicron range. In this paper, 0.5PNN-(0.5-x)PZN-xPZT(x:0.0~0.5) ceramics were fabricated with various mole ratios of the PZT powders prepared by a molten-salt synthesis method and PNN, PZN powders prepared by a columbite precursor method. The formation rate of perovskite phase

Su-Ho Lee; Han-Geun Kim; Hun-Il Choi; Geon Sa-Gong

1997-01-01

243

Dielectric and piezoelectric properties of ZnO and SnO2 co-doping K0.5Na0.5Nbo3 ceramics  

NASA Astrophysics Data System (ADS)

A series of (1-x)K0.5Na0.5NbO3-x(ZnO and SnO2) ceramics were prepared by solid state reaction method and their structures, dielectric and piezoelectric properties were investigated. All samples show pure perovskite phase with typical orthorhombic symmetry at x?0.6%. However, a trace amount of ZnSnO3 was detected at x?0.8%, in addition to the ZnSnO3, some Zn2SnO4 and SnO2 were presented at x?1.0%. The phase transition temperature of orthorhombic-tetragonal (TO-T) and tetragonal-cubic (Tc), the remnant polarization (Pr) and the coercive field (Ec) decreased with increasing x. The dielectric constant (?r), piezoelectric constant (d33) and electromechanical coupling factor (kp) increased with increasing x until x=0.8%, and then decreased with further increasing x. And the optimum piezoelectric properties of ?r=503, d33=124 pC/N and kp=0.398 were obtained. The increase in piezoelectric properties might be due to the increase in density and ZnSnO3 doping.

Li, Z.; Xu, G.; Li, Y.; Sun, A.; Duan, L.; Jiang, J.; Cui, P.

2010-01-01

244

The history of ceramic filters  

Microsoft Academic Search

The history of ceramic filters is surveyed. Included is the history of piezoelectric ceramics. Ceramic filters were developed using technology similar to that of quartz crystal and electro-mechanical filters. However, the key to this development involved the theoretical analysis of vibration modes and material improvements of piezoelectric ceramics. The primary application of ceramic filters has been for consumer-market use. Accordingly,

Satoru Fujishima

2000-01-01

245

Lifetime Modeling based on an Advanced Test Chip Configuration for Lead-free Solder Joints  

Microsoft Academic Search

This paper presents the results of thermo-mechanical lifetime tests. A novel test vehicle was employed to characterize solder joint reliability of miniaturized lead-free tin-silver-copper solder bumps. The test vehicle consists of a stiff ceramic chip (AI2O3) with four corner solder joints assembled on a FR-4 PWB. The distance between the solder joint centers is variable (d= 800\\/1600\\/2400\\/3200 mum). This allows

Bjrn Bhme; Mike Rllig; Steffen Wiese; Klaus-Jrgen Wolter

2006-01-01

246

Failure analysis of lead-free solder joints for high-density packages  

Microsoft Academic Search

Failure analyses of the lead-free and SnPb solder joints of high-density packages such as the plastic ball grid array and the ceramic column grid array soldered on SnCu hot-air solder levelling electroless nickel-immersion gold or NiAu, and organic solderability preservative Entek printed circuit boards are presented. Emphasis is placed on determining the failure locations, failure modes, and intermetallic compound composition

John Lau; Dongkai Shangguan; Todd Castello; Rob Horsley; Joe Smetana; Nick Hoo; Walter Dauksher; Dave Love; Irv Menis; Bob Sullivan

2004-01-01

247

Origin of temperature independent piezoelectric coefficient in Pb(Mg1/3Nb2/3)O3-BaTiO3-PbTiO3 ceramics  

NASA Astrophysics Data System (ADS)

The temperature dependence of piezoelectric resonance frequency, dielectric, and piezoelectric properties of (65-x)[Pb(Mg1/3Nb2/3)O3]-xBaTiO3-35PbTiO3 (x = 0, 1, 2, 3) ceramics has been investigated. Sample compositions with x = 2 and 3 were found to exhibit a large piezoelectric response. Particularly, d31 value was nearly a constant over a temperature range from 150 to 325 K. A broad ferroelectric phase transition tuned by BaTiO3 ratio in the sample was deduced from the dielectric constant, piezoelectric resonance frequency, and Raman spectra. The temperature dependence of the Raman modes wavenumber positions and intensities provides a clear evidence for the occurrence of the phase transition. The temperature-stable piezoelectric response was attributed to the counter-balance of contributions from the dielectric and elastic responses.

Huang, Lizhu; Bulou, Alain; Kassiba, Abdelhadi; Zeng, Jiangtao; Fu, Desheng; Errien, Nicolas; Zheng, Liaoying; Li, Guorong

2013-08-01

248

Available thermal budget in lead-free reflow process  

Microsoft Academic Search

The electronics industry will have to implement lead-free soldering in the near future. Lead-free technology implementation phases are divided into lead-free processes and leadfree product. The prime issue is the component availability and component heat tolerance with the higher soldering temperatures. There is concern about the stability and heat resistance of a range of plastic encapsulated devices, capacitors, filters, connectors

Aulis Tuominen; Pekka Nummenpaa; Timo Liukkonen

2004-01-01

249

Reliability and Leachate Testing of Lead-Free Solder Joints  

Microsoft Academic Search

A test program was started in 2000 at Boeing for the evaluation of the reliability of lead -free solder joints. One lead-free solder was tested for reflow operations (tin\\/3.8%silver\\/0.7%copper) and one solder was tested for wave soldering operations (tin\\/0.7%copper). Three lead-free circuit board finishes were also tested: immersion silver; electrolytic gold on top of nickel; and an OSP (organic solderability

Thomas A. Woodrow

250

Dielectric and piezoelectric properties of SrBi4-xHoxTi4O15 (x=0.00, 0.02, 0.04 and 0.06) ceramics  

NASA Astrophysics Data System (ADS)

The dielectric and piezoelectric properties of SrBi4-xHoxTi4O15 (x=0.00, 0.02, 0.04 and 0.06) ceramics were investigated. SrBi4-xHoxTi4O15 (x=0.00, 0.02, 0.04 and 0.06; SBHT-x) ceramics were synthesized by the conventional solid state reaction sintering method. An X-ray diffraction measurement indicated that a single phase layered perovskite was obtained for all compositions. Studies of dielectric properties with temperature at different frequencies and piezoelectric properties have been carried out.

Mamatha, B.; James, A. R.; Sarah, P.

2010-12-01

251

Ferroelectric and Piezoelectric Properties of Pb(Ni1\\/3Nb2\\/3)0.5(Ti0.7Zr0.3)0.5O3 Ceramics Fabricated by Tape-Casting Process  

Microsoft Academic Search

Pb(Ni1\\/3Nb2\\/3)0.5(Ti0.7Zr0.3)0.5O3 (PNN-PZT) ceramic powders were pre-calcined by solid-state reaction method. PNN-PZT piezoelectric ceramics were fabricated by tape-casting process. The effects of sintering temperature on physical and electrical properties of the PNN-PZT ceramics were studied. The results show that the ceramics sintered at 1225C have the best overall properties, d33 = 780 pC\\/N, ?r = 6.18 10, kp = 0.6,

Hui Wang; Kongjun Zhu; Jinhao Qiu; Jun Luo; Hongli Ji

2010-01-01

252

Modeling of material properties of piezoelectric ceramics taking into account damage development under static compression  

NASA Astrophysics Data System (ADS)

We have carried out static compression tests in the poling direction for PZT ceramics and evaluated the material properties by measuring the resonance and anti-resonance frequencies and electrostatic capacity at regular intervals. Then the variation in the material properties up to fracture was clarified. Also, the development of internal damage was also clarified quantitatively by evaluating a damage variable on the basis of the continuum damage mechanics. The damage variable was calculated from the ratio of the elastic coefficient to its initial value. In the present paper, the development of internal damage was formulated as an evolution equation of the damage variable. In the formulation, a threshold stress leading to the onset of damage was considered. Moreover, the variation in material properties was related to the damage variable and formulated as material functions of the damage variable. The development of internal damage and the variation in material properties were simulated by the equations proposed in the present paper and the validity of the equations was verified by comparing the predictions with experimental results.

Mizuno, M.; Nishikata, T.; Okayasu, M.

2013-10-01

253

Liquid Tin Corrosion and Lead Free Wave Soldering  

Microsoft Academic Search

Corrosion of solder pots and solder pot components in wave soldering equipment has been reduced with the introduction of corrosion resistant coatings and improved lead free solder alloys. The latest trends in protecting wave solder machine components from liquid metal corrosion by lead free solder alloys will be presented in order to provide guidelines for evaluating existing equipment as well

Jim Morris; Matthew J. O'Keefe; Martin Perez

254

NanoComposite Lead-Free Interconnect and Reliability  

Microsoft Academic Search

Lead free solder bumping requirements have challenged researchers to develop new technologies to achieve fine pitch interconnects. ITRS has predicts that by 2017 the industry will require 70 micron pitch area array lead free interconnects for flip chips. This paper describes bumping, assembly and reliability evaluation of a new nano composite 20 micron pitch interconnect technology. Nanoparticles are the most

Ravi Doraiswami; Rao Tummala

2005-01-01

255

Infant mortality failures of lead free solder joints  

Microsoft Academic Search

Two goals of the work - verification of suitability of mechanical tests of solder joints reliability and infant mortality (early failures) of lead-free joints are selected. The results of reliability tests of lead - free solder joints of SMT resistors showed a tendency to increase of infant mortality failure rate comparing to SnPb eutectic joints. These new results are presented.

M. Szwech; W. Niedzwiedz; Z. Drozd

2009-01-01

256

Study of Constant Torsion Assembly Method of Piezoelectric Transducer Based on PC Control  

Microsoft Academic Search

The piezoelectric transducer plays a key role in the ultrasonic equipment. In the assembly process of piezoelectric transducer with traditional method, the torsion and the pressure have some fluctuations, and as a result, in the process of using the piezoelectric transducer, the electric-acoustic transformation efficiency of the piezoelectric transducer gets lower, the temperature of the piezoelectric transducer rises, piezoelectric ceramic

Zhang Yundian; Yu Fang; Chen Yan; Zhang Zhixiao

2006-01-01

257

Piezoelectric materials used in underwater acoustic transducers  

SciTech Connect

Piezoelectric materials have been used in underwater acoustic transducers for nearly a century. In this paper, we reviewed four different types of piezoelectric materials: piezoelectric ceramics, single crystals, composites, and polymers, which are widely used in underwater acoustic transducers nowadays. Piezoelectric ceramics are the most dominant material type and are used as a single-phase material or one of the end members in composites. Piezoelectric single crystals offer outstanding electromechanical response but are limited by their manufacturing cost. Piezoelectric polymers provide excellent acoustic impedance matching and transducer fabrication flexibility although their piezoelectric properties are not as good as ceramics and single crystals. Composites combined the merits of ceramics and polymers and are receiving increased attention. The typical structure and electromechanical properties of each type of materials are introduced and discussed with respect to underwater acoustic transducer applications. Their advantages and disadvantages are summarized. Some of the critical design considerations when developing underwater acoustic transducers with these materials are also touched upon.

Li, Huidong; Deng, Zhiqun; Carlson, Thomas J.

2012-07-07

258

Prototyping of radially oriented piezoelectric ceramic-polymer tube composites using fused deposition and lost mold processing techniques  

NASA Astrophysics Data System (ADS)

Piezoelectric tube composite hydrophones of 3-1, 3-2, and 2-2 connectivity were developed using Fused Deposition (FD) and lost mold processing (LMP). In this work, a new series of thermoplastic binder formulations, named the ECG series, were developed for the FD process. The ECG-9 formulation exhibits mechanical, thermal, and rheological properties suitable for the Fused Deposition of functional lead zirconate titanate ceramic devices. This binder consists of 100 parts (by weight) Vestoplast 408, 20 parts Escorez 2520, 15 parts Vestowax A-227, and 5 parts Indopol H-1500. Oleic acid, oleyl alcohol, stearic acid, and stearyl alcohol (in toluene) were tested for use as a dispersant in the PZT/ECG-9 system. It was found that stearic acid adsorbs the most onto PZT powder, adsorbing 8.1 mg/m2. Using stearic acid, solutions of increasing concentration (5.0--50.0 g/l) were measured for adsorption. It was found that 30.0 g/l is the minimum concentration necessary for optimum surface coverage. The surfactant-coated powder was compounded with ECG-9 binder to create a 54 vol.% mix. The mix was extruded using a single screw extrusion apparatus into continuous lengths (>30 m) of 1.78 mm diameter filament. Fused Deposition was used to create composite designs of 3-1, 3-2, and 2-2 connectivity. After sintering, samples exhibit a sintered density greater than 97%. Sanders Prototyping (SPI) was used to manufacture molds for use with LMP techniques. Molds of 3-1, 3-2, and 2-2 connectivity were developed. The molds were infiltrated with a 55 vol.% aqueous based PZT slurry. The parts were subjected to a binder decomposition cycle, followed by sintering. Resultant samples were highly variable due to random macro-pores present in the samples after sintering. The resultant preforms were embedded in epoxy, and polished to dimensions of 8.0 mm inside diameter (ID), 14.0 mm outside diameter (OD), and 10.0 mm length (l) the OD and l dimensions are accurate to +/--2%, while the ID is accurate to +/--5%. Samples were corona poled, and the electromechanical properties were evaluated. Dielectric constant (K), hydrostatic charge coefficients (dh), and radial displacements (ur) were measured. Of the seven composite types studied, the FD-based composites with 3-2 connectivity exhibited the highest average dh of 42.4 pCN. The same 3-2 composites exhibited the highest dhgh (FOM) of 140 fm2/N.

McNulty, Thomas Francis

259

An integrated microfluidic chip with 40 MHz lead-free transducer for fluid analysis  

SciTech Connect

The design, fabrication, and evaluation of a high-frequency transducer made from lead-free piezoceramic for the application of microfluidic analysis is described. Barium strontium zirconate titanate [(Ba{sub 0.95}Sr{sub 0.05})(Zr{sub 0.05}Ti{sub 0.95})O{sub 3}, abbreviated as BSZT] ceramic has been chosen to be the active element of the transducer. The center frequency and bandwidth of this high-frequency ultrasound transducer have been measured to be 43 MHz and 56.1%, respectively. The transducer was integrated into a microfluidic channel and used to measure the sound velocity and attenuation of the liquid flowing in the channel. Results suggest that lead-free high-frequency transducers could be used for in situ analysis of property of the fluid flowing through the microfluidic system.

Lee, S. T. F.; Lam, K. H.; Lei, L.; Zhang, X. M.; Chan, H. L. W. [Department of Applied Physics and Materials Research Centre, The Hong Kong Polytechnic University, Kowloon (Hong Kong)

2011-02-15

260

Development of lead-free solders for hybrid microcircuits  

SciTech Connect

Extensive work has been conducted by industry to develop lead-free solders for electronics applications. The driving force behind this effort is pressure to ban or tax the use of lead-bearing solders. There has been further interest to reduce the use of hazardous chemical cleaners. Lead-free soldering and low-residue, ``no clean`` assembly processing are being considered as solutions to these environmental issues. Most of the work has been directed toward commercial and military printed wiring board (PWB) technology, although similar problems confront the hybrid microcircuit (HMC) industry, where the development of lead-free HMC solders is generally lagging. Sandia National Laboratories is responsible for designing a variety of critical, high reliability hybrid components for radars. Sandia has consequently initiated a project, as part of its Environmentally Conscious Manufacturing program, to develop low-residue, lead-free soldering for HMCs. This paper discusses the progress of that work.

Hosking, F.M.; Vianco, P.T.; Frear, D.R.; Robinson, D.G.

1996-01-01

261

Lead-Free Experiment in a Space Environment.  

National Technical Information Service (NTIS)

This Technical Memorandum addresses the Lead-Free Technology Experiment in Space Environment that flew as part of the seventh Materials International Space Station Experiment outside the International Space Station for approximately 18 months. Its intent ...

J. F. Blanche S. M. Strickland

2012-01-01

262

Development of Sn-Zn-Cu lead free solder  

Microsoft Academic Search

Sn-Zn based lead free solder is one type of promising candidate to replace Sn-Pb eutectic solder due to its low cost and melt temperature which near to Sn-Pb eutectic solder. The Sn-Zn-Cu lead free solder was developed by alloying Sn with Zn and Cu in this paper. The effect of Zn and Cu content on the wettability of solder to

Yang Min; Liu Xiuzhong; Liu Xinghong; Dai Jiahui

2010-01-01

263

Failure analysis techniques for lead-free solder joints  

Microsoft Academic Search

Purpose This paper aims to describe and document the application of commonly utilized solder joint failure analysis techniques to lead-free solder joints. Design\\/methodology\\/approach Traditional failure analysis techniques, including visual inspection, X-ray radiography, mechanical strength testing, dye and pry, metallography, microscopy and photomicrography, are reviewed. These techniques are demonstrated as applied to lead-free and tin lead solder joints. Common

Todd Castello; Dan Rooney; Dongkai Shangguan

2006-01-01

264

Lead-Free Soldering - Where The World Is Going  

Microsoft Academic Search

Lead-free soldering for electronic industry is a segment of glob al trend toward lead-free environment. Although initiated in U.S. in early 1990's, it advanced much more rapidly in Japan and Europe. This differentiation in Pb -free progress triggered great concerns of users of Pb -containing solders about maintaining busi ness opportunity, therefore further expedites the advancement of Pb -free soldering

Ning-Cheng Lee

265

High drop test reliability: lead-free solders  

Microsoft Academic Search

Recently, preventing environmental pollution, lead-free (Pb-free) solders are about to replace tin-lead (Sn-Pb) eutectic solders. Sn-Ag-Cu alloys are leading candidates for lead free solders. Sn-Ag-Cu-P was developed last year, but Sn-Ag-Cu-P alloys were not satisfactory to meet severe customer requirements like thermal aging process followed by drop tests. To improve drop test performance after the thermal aging process, a combination

M. Amagai; Yoshitaka Toyoda; Tsukasa Ohnishi; Satom Akita

2004-01-01

266

Fatigue Life Assessment for Lead-Free Solder Joints  

Microsoft Academic Search

\\u000a The authors will indicate the basic reliability problems associated with use of lead-free solder joints. They investigated\\u000a the thermal fatigue reliability of lead-free solder joints, and focused their attention on the formation of the intermetallic\\u000a compound and its effect on the initiation and propagation of the fatigue cracks. An isothermal fatigue test method was used\\u000a to improve the efficiency of

Masaki Shiratori; Qiang Yu

267

Lead-free solder assembly: impact and opportunity  

Microsoft Academic Search

Tlicrc Ius been major interest in Lead-free soldcring within the electronics assembly industry for the last scvcral years. and tlds will continue with the agrccmcnt on the languagc and implementation dates of the WEEWROHS lcgisliltiou in the EU. This paper will focus on several topics critical lo the implementation of lead-free soldering. Thesc topics include tlie impact of Tin-silver-copper as

E. Bradley

2003-01-01

268

Novel Testing Instrument for Lead-Free Solder Characterization  

Microsoft Academic Search

The European Union Restriction of Hazardous Sub- stances Directive of 2006 has revolutionized the use of materials for electronic packaging: tin-lead solder has had to be replaced with lead-free solder. While years of experience and data acquired in the field are available for tin-lead solder, the same cannot be said for lead-free solder. The lack of data on these new

D. Di Maio; O. Thomas; M. Dusek; C. Hunt

2011-01-01

269

LEAD-FREE REWORK PROCESS FOR CHIP SCALE PACKAGES  

Microsoft Academic Search

Legislation against the use of lead in electronics has been the driving force behind the use of lead-free solders, surface finishes, and component lead finishes. The major concern in using lead-free solders in the assembly and rework Chip Scale Packages (CSPs) is the relatively high temperatures that the components and the boards experience. Fine-pitch CSPs have very low standoff heights

Arun Gowda; K. Srihari

270

Topics in electronic ceramics  

Microsoft Academic Search

Four topics in the field of electronic ceramics are reviewed: multilayer ceramic capacitors, piezoelectric ceramics, electrooptic ceramics, and ferroelectric thin films. They all are related to ferroelectric ceramic materials. The scope of this review is limited to oxide compounds, because oxide ferroelectrics, for the most part, exhibit the most useful properties and have found the most applications. The underlying physical

S. L. Swartz

1990-01-01

271

SINTERING OF LEAD-FREE (K0.5Na0.5)NbO3 BASED SOLID SOLUTION  

Microsoft Academic Search

In this study lead-free solid solution (K0.5Na0.5)NbO3 was prepared, structure, dielectric parameters of ceramics were investigated. The doping of sintering aids did not affect the crystallographic structure of the ceramics significantly; all ceramic samples had a single-phase perovskite structure. Added elements CdO, ZnO, MnO2, V2O5 effectively decreased the sintering temperature of KNN by 5080C. All sintering aids influenced sinterability, microstructure

I. SMELTERE; M. DAMBEKALNE; M. LIVINSH; M. DUNCE; A. MISHNOV; V. ZAULS

2009-01-01

272

Rapid Prototyping of Novel Piezoelectric Composites  

Microsoft Academic Search

Piezoelectric ceramic-polymer composites have been conceptualized, prototyped, fabricated by rapid prototyping in order to surpass those fabricated with traditional processing methods in novelty as well as performance. Rapid prototyping offers unmatched design and fabrication flexibility in achieving structural complexity and hierarchy in developing piezoelectric composites. A detailed account of all salient aspects of Fused Deposition of Ceramics (FDC) and Fused

A. Safari; E. K. Akdogan

2006-01-01

273

Enhanced piezoelectric properties of (Na0.5+y+zK0.5-y)(Nb1-xTax)O3 ceramics  

NASA Astrophysics Data System (ADS)

A- and B-site ratios in (Na0.5+y+zK0.5-y)(Nb1-xTax)O3 ceramics with ABO3 structure were investigated to differentiate the effects of polymorphic phase transition (PPT), morphotropic phase boundary (MPB), and Na nonstoichiometry on piezoelectric coefficient (d33). MPB was intrinsically determined by the ratio between Na and K, whereas PPT was extrinsically controlled by Ta substitution. PPT temperature between orthorhombic and tetragonal phases (TO-T) was reduced to room temperature at x = 0.45. d33 was increased to 310 pC/N at y = 0.03 and z = 0 by the combined effects of PPT and MPB and was further enhanced to 333 pC/N by the Na nonstoichiometry at z = 0.015 with improved density.

Sung, Y. S.; Baik, S.; Lee, J. H.; Ryu, G. H.; Do, D.; Song, T. K.; Kim, M. H.; Kim, W. J.

2012-07-01

274

High-field and high-Tc piezoelectric ceramics based on Bi(Ga,Fe)O3-PbTiO3 crystalline solutions  

Microsoft Academic Search

The gallium-modified bismuth ferrite-lead titanate compositions of 0.4Bi(Ga0.4Fe0.6)O3-0.6PbTiO3 (0.4BGF-0.6PT), has been investigated for the potential as a high-field and high-temperature piezoelectric ceramic. The crystalline solutions of 0.4BGF-0.6PT were fabricated by using the solid-state reaction method. X-ray diffraction analysis revealed that 0.4BGF-0.6PT has a tetragonal perovskite structure. The Curie temperature Tc of 0.4BGF-0.6PT was determined to be 540 C. Our 0.4BGF-0.6PT

Jinrong Cheng; Zhongyan Meng; L. Eric Cross

2005-01-01

275

Lead-free nanogenerator made from single ZnSnO3 microbelt.  

PubMed

We demonstrated a single-microbelt nanogenerator first made using a ZnSnO(3) microbelt that generated an output power of ?3 nW under a compressive and releasing strain of 0.8-1%. The ZnSnO(3) nanobelts/microbelts were synthesized using a vapor transfer process at 1173 K. The X-ray diffraction pattern shows that the microbelts belong to ZnSnO(3) with rhombohedral structure. An individual ZnSnO(3) microbelt was bonded at its ends on a flexible polystyrene substrate as a nanogenerator, which gives an output voltage and current of 100 mV and 30 nA, respectively, corresponding to an energy conversion efficiency of 4.2-6.6% (based on 0.8-1% strain). Our results show that ZnSnO(3) microbelts are one of the highly promising materials for lead-free piezoelectric energy harvesting. PMID:22482511

Wu, Jyh Ming; Xu, Chen; Zhang, Yan; Wang, Zhong Lin

2012-04-11

276

EFFECT OF CALCINATION TEMPERATURE ON THE PIEZOELECTRIC CHARACTERISTICS OF Pb(Mn1\\/3Nb2\\/3)O3Pb(Ni1\\/3Nb2\\/3)O3Pb (Zr0.50Ti0.50)O3 CERAMICS  

Microsoft Academic Search

PMN-PNN-PZT ceramics doped with sintering aids such as Li2CO3 and Na2CO3 were fabricated using two-stage calcination method and their structural and piezoelectric properties were investigated according to the 1 calcination temperature in order to develop ceramic composition for low loss and low temperature sintering multilayer piezoelectric actuator. The coulombite phase was successfully synthesized at 1050C, resulting in increase of perovskite

Juhyun Yoo; Dohyung Kim; Hyunsun Song; Dong Soo Paik; Dong Heon Kang

2008-01-01

277

EFFECT OF CALCINATION TEMPERATURE ON THE PIEZOELECTRIC CHARACTERISTICS OF Pb(Mn1\\/3Nb2\\/3)O3Pb(Ni1\\/3Nb2\\/3)O3Pb(Zr0.50Ti0.50)O3 CERAMICS  

Microsoft Academic Search

PMN-PNN-PZT ceramics doped with sintering aids such as Li2CO3 and Na2CO3 were fabricated using two-stage calcination method and their structural and piezoelectric properties were investigated according to the 1st calcination temperature in order to develop ceramic composition for low loss and low temperature sintering multilayer piezoelectric actuator. The coulombite phase was successfully synthesized at 1050C, resulting in increase of perovskite

JUHYUN YOO; DOHYUNG KIM; HYUNSUN SONG; DONG SOO PAIK; DONG HEON KANG

2007-01-01

278

High temperature piezoelectric drill  

NASA Astrophysics Data System (ADS)

The current NASA Decadal mission planning effort has identified Venus as a significant scientific target for a surface in-situ sampling/analyzing mission. The Venus environment represents several extremes including high temperature (460C), high pressure (~9 MPa), and potentially corrosive (condensed sulfuric acid droplets that adhere to surfaces during entry) environments. This technology challenge requires new rock sampling tools for these extreme conditions. Piezoelectric materials can potentially operate over a wide temperature range. Single crystals, like LiNbO3, have a Curie temperature that is higher than 1000C and the piezoelectric ceramics Bismuth Titanate higher than 600C. A study of the feasibility of producing piezoelectric drills that can operate in the temperature range up to 500C was conducted. The study includes the high temperature properties investigations of engineering materials and piezoelectric ceramics with different formulas and doping. The drilling performances of a prototype Ultrasonic/Sonic Drill/Corer (USDC) using high temperate piezoelectric ceramics and single crystal were tested at temperature up to 500C. The detailed results of our study and a discussion of the future work on performance improvements are presented in this paper.

Bao, Xiaoqi; Scott, James; Boudreau, Kate; Bar-Cohen, Yoseph; Sherrit, Stewart; Badescu, Mircea; Shrout, Tom; Zhang, Shujun

2009-03-01

279

Wettability analysis of tin-based, lead free solders  

SciTech Connect

The overall program is comprised of two efforts. The first effort studies the wettability of tin-based, lead free solders on two commonly used substrate materials: copper and gold-nickel plated Kovar{trademark}. The evaluation is being conducted by the meniscometer/wetting balance technique which uses the contact angle as the primary metric to quantify wettability. Information about the rate of wetting is also obtainable with this test. The second part of the program is comprised of an assessment of the solderability of actual circuit board assemblies (surface mount and through-hole). This report will describe data from the wettability analysis of lead free solders on copper.

Vianco, P T; Hosking, F M; Rejent, J A

1992-01-01

280

Ceramicelectrode interaction in PZT and PNNPZT multilayer piezoelectric ceramics with AG\\/PD 70\\/30 inner electrode  

Microsoft Academic Search

Pb(Zr0.53Ti0.47)O3(PZT) and PbNi1\\/3Nb2\\/3O3-PZT (PNNPZT) multilayers with Ag\\/Pd 70\\/30 inner electrodes have been studied from the point of view of the ceramicelectrode interaction. PZT multilayers have shown silver free ceramic layers, and no lead has been detected in the electrode after sintering. Silver transport through the ceramic is avoided because of low open porosityclose porosity transition temperature. This transition seems to

A. C Caballero; E Nieto; P Duran; C Moure; M Kosec; Z Samardzija; G Drazic

1997-01-01

281

High Energy, Lead-Free Ignition Formulation for Thermate.  

National Technical Information Service (NTIS)

An efficient ignition formulation for thermate was developed during the XM89 Enhanced Incendiary Grenade program to use as an alternative to the standard lead oxide-containing formulation used in the AN-Ml4 thermate grenade. This lead-free formulation has...

G. V. Tracy E. Song

2002-01-01

282

Minimizing flux spatter during lead-free reflow assembly  

Microsoft Academic Search

Purpose The leaching of lead from electronic components in landfills to ground water is harmful to health and to the environment. Increasing concern over the use of lead in electronics manufacturing has led to legislation to restrict its use as a joining material. Consequently, significant recent research efforts have been geared to identification of suitable lead-free solder pastes. Typically,

Deepak Manjunath; Satyanarayan Iyer; Shawn Eckel; Purushothaman Damodaran; Krishnaswami Srihari

2006-01-01

283

Reliability of the aging lead free solder joint  

Microsoft Academic Search

Solder materials demonstrate evolving microstructure and mechanical behavior that changes significantly with environmental exposures such as isothermal aging and thermal cycling. These aging effects are greatly exacerbated at higher temperatures typical of thermal cycling qualification tests for harsh environment electronic packaging. In the current study, mechanical measurements of thermal aging effects and material behavior evolution of lead free solders have

Hongtao Ma; Jeffrey C. Suhling; Pradeep Lall; Michael J. Bozack

2006-01-01

284

Investigation of high Curie temperature (1-x)BiSc{sub 1-y}Fe{sub y}O{sub 3}-xPbTiO{sub 3} piezoelectric ceramics  

SciTech Connect

Ceramics around the morphotropic phase boundary (MPB) in the (1-x)BiSc{sub 1-y}Fe{sub y}O{sub 3}-xPbTiO{sub 3} solid solution were fabricated. For y=0.5, ceramics were single phase, and piezoelectric coefficients (d{sub 33}) and electromechanical coupling coefficients (k{sub p}) for MPB compositions were 300 pC/N and 0.49, respectively; a level of piezoelectric activity similar to that of hard, lead zirconate titanate compositions but with T{sub C}approx60 deg. C higher at approx440 deg. C. For ceramics with y>=0.7, dielectric measurements in combination with diffraction contrast transmission electron microscopy revealed the existence of two ferroelectric phases for most PbTiO{sub 3} contents studied. The presence of two ferroelectric phases was associated with a decrease in piezoelectric activity and although raw materials costs for y=0.7 and 0.8 with respect to y=0 were significantly lower (less Sc{sub 2}O{sub 3}) and T{sub C} greater (approx500 deg. C), d{sub 33} (approx100 pC/N) and k{sub p} (0.18) were too low to be commercially useful for actuator applications.

Sterianou, I.; Sinclair, D. C.; Reaney, I. M. [Department of Engineering Materials, The University of Sheffield, Sheffield S1 3JD (United Kingdom); Comyn, T. P.; Bell, A. J. [Institute for Materials Research, University of Leeds, Leeds LS2 9JT (United Kingdom)

2009-10-15

285

Highly textured (Na 1\\/2Bi 1\\/2) 0.94Ba 0.06TiO 3 ceramics prepared by the screen-printing multilayer grain growth technique  

Microsoft Academic Search

The screen-printing multilayer grain growth (MLGG) technique was successfully applied to perovskite-structured lead-free piezoelectric ceramics. Highly textured (Na1\\/2Bi1\\/2)0.94Ba0.06TiO3 ceramics with (100) orientation were firstly fabricated by MLGG method with (or without) template particles. The MLGG approach using anisotropic Bi4Ti3O12 templates resulted in >90% grain orientation, whereas the same approach without template particles resulted in high orientation degree. The grain orientation

Mengjia Wu; Yongxiang Li; Dong Wang; Qingrui Yin

2008-01-01

286

Creep Analysis of a Lead-free Surface Mount Device  

Microsoft Academic Search

In this paper finite element analysis (FEA) is used to understand the effect of a non-uniform temperature distribution on the creep and fatigue behaviour of lead-free solder joints in an electronic assembly comprising of a chip resistor mounted on printed circuit board (PCB). Solder joints in surface mount devices (SMDs) operate over a temperature range as extreme as -55degC to

Pradeep Hegde; David Whalley; V. V. Silberschmidt

2007-01-01

287

An Approach for Impression Creep of Lead Free Microelectronic Solders  

Microsoft Academic Search

Currently, the microelectronics industry is transitioning from lead-containing to lead-free solders in response to legislation in the EU and Japan. Before an alternative alloy can be designated as a replacement for current Pb-Sn extensive testing must be accomplished. One major characteristic of the alloy that must be considered is creep. Traditionally, creep testing requires numerous samples and a long tin,

Onofrio A. Anastasio

2002-01-01

288

Development of fluxes for lead-free solders containing zinc  

Microsoft Academic Search

New lead-free solders based on the Sn-Zn eutectic (92 wt. pct Sn - 8 wt. pct Zn) are promising candidates to replace near-eutectic tin-lead solders because these solders are less expensive than alternatives such as Sn-Ag eutectic base solders and the melting point of the tin-zinc eutectic (198 C) is much closer to melting point of commonly used tin-lead eutectic

S. Vaynman; M. E. Fine

1999-01-01

289

Analysis of intermetallic compounds in lead-free solders  

Microsoft Academic Search

Intermetallic compounds (IMCs) are essential part of lead-free solders microstructure. In 96.5Sn3Ag0.5Cu (SAC305) solder is dominant element tin (Sn). But despite this Sn dominancy only 3% weight contain of silver (Ag) has influence on final structure of solid solder joint. Fundamental impact on strength properties of solder joint has also interaction between the solder and printed circuit board (PCB) pad.

A. Pietrikova; J. Durisin; J. Urbancik; J. Bansky

2009-01-01

290

Finite element analysis of lead-free drop test boards  

Microsoft Academic Search

Lead-free CSP assemblies were drop tested according to the JEDEC standard (JESD-B111) and the finite element analysis of the test assembly was carried out to simulate the strain and stress distributions generated in the assemblies. The vibration of the board during the test was measured with strain gauges and the results were compared to the FE model predictions. The eigenfrequency

Pekka Marjamki; Toni Mattila; Jorma Kivilahti

2005-01-01

291

Lead-free wave soldering development for pcb assembly  

Microsoft Academic Search

The scope of work entailed determining the performance of Sn0.7Cu and Sn3.8Ag0.7Cu lead-free alloys for wave soldering applications in combination with lead-he components, board fmishes, different flux types and operating atmospheres using a production scale wave soldering machine. The vertical solder filling of througb holes using passive components such as connecton was excellent for PCBs with NiAu, Ag and OSP

Vasudivan Sunappan; Peter Collier

2003-01-01

292

Failure of lead-free solder joint under thermal cycling  

Microsoft Academic Search

Microelectronic devices are often subjected to environmental and power cycling thermal loads. Thermal cycling and the shear forces lead to many failures in microelectronic devices. The most common failure is an open in one or more of the input\\/output (I\\/O). The open is the result of a cracked or damaged interconnects, whether it is a lead-free solder joint. Thermal cycling

Yung-Wen Wang; Mei-Ling Wu

2011-01-01

293

Constitutive models of creep for lead-free solders  

Microsoft Academic Search

The constitutive modeling of creep has been extensively studied due to the important of the creep failure mode in solder joints.\\u000a However, there are very few studies that considered room temperature aging contributions in their creep modeling studies.\\u000a This study investigated constitutive modeling of creep of solders by taking into account the possible contribution room temperature\\u000a aging. Lead-free solder (Sn4.0Ag0.5Cu)

Hongtao Ma

2009-01-01

294

NEW MEXICO TECH LEAD-FREE SOLDER RESEARCH  

Microsoft Academic Search

In recent years a growing concern for lead-free solder has propelled industry to re-evaluate surface mount technology (SMT) production. This is based on the European Union's reduction of hazardous substances (RoHS) directive for a cleaner environment. Military and Aerospace industries, though they have been given exemption from this directive, are very dependent upon commercial industry that must be RoHS compliant.

Stephen Bracht; Aghavni Ball; Lisa Salerno

295

Aging of piezoelectric properties in Pb(MgNb)O3-Pb(ZrTi)O3 multilayer ceramic actuators  

NASA Astrophysics Data System (ADS)

Aging characteristics of 0.2(PbMg1/3Nb2/3O3)-0.8(PbZr0.475Ti0.525O3) multilayer ceramic actuators have been investigated by applying rectified ac bias. Multilayer ceramic actuators 555 mm3 in size were fabricated by tape-casting methods. X-ray diffraction analyses were performed to compare crystalline structures and lattice parameters. Effective electromechanical coupling coefficient keff and pseudopiezoelectric constant d33 were calculated and discussed. Different rectified ac electric biases were applied to the actuators to investigate aging behavior in the multilayer ceramic actuators. The aging dependencies of cycles and electric fields were simulated and fitted to the linear logarithmic stretched exponential law.

Koh, Jung-Hyuk; Jeong, Soon-Jong; Ha, Mun-Su; Song, Jae-Sung

2004-07-01

296

A micromachining process for die-scale pattern transfer in ceramics and its application to bulk piezoelectric actuators  

Microsoft Academic Search

This paper reports on a batch mode planar pattern transfer process for bulk ceramics, glass, and other hard, brittle, nonconductive materials suitable for micromachined transducers and packages. The process is named LEEDUS, as it combines lithography, electroplating, batch mode micro electro-discharge machining (?EDM) and batch mode micro ultrasonic machining (?USM). An electroplating mold is first created on a silicon or

Tao Li; Yogesh B. Gianchandani

2006-01-01

297

Dielectric and piezoelectric properties of stacked and plated PVDF, P(VDF\\/TeFe), P(VDF\\/TrFE) and ceramic\\/rubber composite thick films  

Microsoft Academic Search

We measured the properties of nine different piezoelectric materials, as supplied, and as further processed to increase their hydrostatic sensitivity. We studied the effect of electrode material, stiffening plates, and multiple layering on the piezoelectric and dielectric properties of the thick piezopolymer films. Dielectric measurements and thickness mode d3t, lateral mode d31 (d32), and hydrostatic mode dh piezoelectric coefficients were

Philip E. Bloomfield

1994-01-01

298

Piezoelectric dispenser based on a piezoelectric-metal-cavity actuator  

NASA Astrophysics Data System (ADS)

A piezoelectric dispenser has been fabricated based on the idea of a piezoelectric-metal-cavity (PMC) actuator. The PMC actuator consists of a metal ring sandwiched between two identical piezoelectric unimorphs. The radial contraction of the piezoelectric ceramic is converted into a flextensional motion of the unimorph, causing a large flexural displacement in the center part of the actuator. With the PMC actuator as a fluid chamber, the large flexural actuation can be used to produce the displacement needed to eject fluid. By applying an appropriate voltage to the piezoelectric unimorphs, a drop-on-demand ejection of ink or water can be achieved. The efficiency of fluid ejection can be enhanced after installing a valve in the fluid chamber. With the simple PMC structure, the dispenser can be operated with a low driving voltage of 12-15 V.

Lam, K. H.; Sun, C. L.; Kwok, K. W.; Chan, H. L. W.

2009-07-01

299

Piezoelectric Properties of Li-Doped (K0.48Na0.52)NbO3 Ceramics Synthesized Using Hydrothermally-Derived KNbO3 and NaNbO3 Fine Powders  

NASA Astrophysics Data System (ADS)

[Lix(Na0.52K0.48)1-x]NbO3 (0 ? x ? 0.091) ceramics were synthesized using hydrothermal powders and the lithium doping content was controlled to optimize their piezoelectric properties. The raw KNbO3 and NaNbO3 powders were obtained separately by a hydrothermal method and LiNbO3 powders were prepared by milling a commercial LiNbO3 single crystal. These powders were mixed with ethanol at a molar ratio LiNbO3: (Na0.52K_{0.48)NbO3}= x : 1-x. The synthesized powders were sintered at 1060--1120 C for 2 h. We succeeded in obtaining highly dense [Lix(Na0.52K0.48)1-x]NbO3 ceramics using hydrothermal powder. The X-ray diffraction patterns revealed that the crystal phase changed from orthorhombic to tetragonal at around x = 0.06. At this morphotropic phase boundary (MPB), the c/a ratio changed from 1.016 to 1.024 and the highest piezoelectric constant was obtained with the chemical component of [Li0.065(K0.48Na0.52)0.935]NbO3. The obtained piezoelectric properties were as follows: k33 = 0.51, \\varepsilon33T/\\varepsilon0 = 836, c33E = 46 GPa, d33 = 203 pC/N, and Tc = 482 C.

Maeda, Takafumi; Hemsel, Tobias; Morita, Takeshi

2012-09-01

300

Piezoelectric Polymers.  

National Technical Information Service (NTIS)

The purpose of this review is to detail the current theoretical understanding of the origin of piezoelectric and ferroelectric phenomena in polymers; to present the state-of-the-art in piezoelectric polymers and emerging material systems that exhibit prom...

J. S. Harrison Z. Ounaies

2001-01-01

301

Classical Piezoelectricity: Is the Theory Complete.  

National Technical Information Service (NTIS)

This paper cites experimental evidences which show that the classical theory of piezoelectricity is not complete in describing the responses of ferroelectric ceramics. There are also some preliminary evidences to show that the theory as applied to piezoel...

P. J. Chen

1985-01-01

302

Development of a piezoelectric sensor to measure angular acceleration  

Microsoft Academic Search

An angular acceleration measurement system using a piezoelectric material is described. The piezoelectric material used in the sensor was either a pre-polarised PVDF film or a polymer\\/ceramic piezoelectric composite of (PTCa:P(VDF\\/TrFE) 50:50 vol %)

R. Marat-Mendes; C. J. Dias; J. N. Marat-Mendes

1999-01-01

303

Giant energy density in [001]-textured Pb(Mg1/3Nb2/3)O3-PbZrO3-PbTiO3 piezoelectric ceramics  

SciTech Connect

Pb(Zr,Ti)O3 (PZT) based compositions have been challenging to texture or grow in a single crystal form due to the incongruent melting point of ZrO2. Here we demonstrate the method for achieving 90% textured PZT-based ceramics and further show that it can provide highest known energy density in piezoelectric materials through enhancement of piezoelectric charge and voltage coefficients (d and g). Our method provides more than 5 increase in the ratio d(textured)/d(random). A giant magnitude of d g coefficient with value of 59 000 10 15 m2 N 1 (comparable to that of the single crystal counterpart and 359% higher than that of the best commercial compositions) was obtained.

Yan, Yongke [Bio-Inspired Materials and Devices Laboraory (BMDL); Cho, Kyung-Hoon [Bio-Inspired Materials and Devices Laboraory (BMDL); Maurya, Deepam [ORNL; Kumar, Amit [ORNL; Kalinin, Sergei V [ORNL; Khachaturyan, Armen [State University of New Jersey, The; Priya, Shashank [ORNL

2013-01-01

304

Effect of lead content on the structure and piezoelectric properties of hard type lead titanatezirconate ceramics  

Microsoft Academic Search

In the present investigation we studied the effect of lead content on a hard type ceramics starting from lack to excess PbO. Specimens of Pbx(Mn0.017Sb0.033Zr0.48Ti0.47)O3 with 0.96?x?1.06 were prepared by conventional oxide mixing technique and sintered at temperatures between 1280 and 1350C. In samples with lower Pb concentration the pyrochlore phase appeared, while in those with higher Pb an excess

C. Miclea; C. Tanasoiu; L. Amarande; A. Gheorghiu; I. Spanulescu; C. Plavitu; C. T. Miclea; M. C. Cioangher; L. Trupina; A. Iuga

2007-01-01

305

Diffuse phase transition in Li0.12Na0.88NbO3 piezoelectric ceramics  

NASA Astrophysics Data System (ADS)

The morphotropic phase boundary composition viz. lithium sodium niobate, Li0.12Na0.88NbO3, (LNN-12) was prepared by conventional solid state reaction and sintering route. The temperature dependent permittivity response near transition temperature showed a diffused phase transition (DPT). The degree of diffuseness, ?, using the modified Curie-Weiss law, was found to be 1.92, indicative of almost-complete diffuse phase transition. The planar coupling constant kp, and mechanical quality factor Qm, measured by resonance-antiresonance method, were 0.17 and 413 respectively. These parameter values make LNN-12 ceramic an attractive candidate for transducers applications.

Mitra, Supratim; Kulkarni, Ajit R.; Prakash, Om

2013-02-01

306

An experience of PNN-PT-PZ high-k piezoelectric ceramics aiming for medical imaging transducers  

Microsoft Academic Search

Beyond the k=0.7 class PZT families, our ever-lasting desire is to have more k to extend bandwidth and efficiency. A material within ceramic family, PNN-PT-PZ (PbNi1\\/3Nb2\\/3O3 -PbTiO3-PbZrO3), is an easier candidate, however, with k=0.8 around, in between PZT family and single crystal family. Although including a die-pressing step, the material can be prepared using conventional solid solution method similar to

Y. Takeuchi; M. Kondo

2001-01-01

307

Feature of morphotropic phase boundary of yBiGaO{sub 3}-(1-x-y)BiScO{sub 3}-xPbTiO{sub 3} high-temperature piezoelectric ceramics  

SciTech Connect

yBiGaO{sub 3}-(1-x-y)BiScO{sub 3}-xPbTiO{sub 3} (BGSPT) ternary piezoelectric ceramics were fabricated by using conventional mixed oxide ceramic processing. It was found that the introduction of BiGaO{sub 3} into BiScO{sub 3}-PbTiO{sub 3} system would cause a shift of morphotropic phase boundaries (MPBs), from x=0.64, y=0 to x=0.56, y=0.155; and an increase of Curie temperature (T{sub C}) near MPB, from 450 up to 494 deg. C, respectively. BGSPT ceramics possessed higher T{sub C} ({approx}494 deg. C) and high piezoelectric coefficient (d{sub 33}{approx}180 pC/N), and showed the different rule of the Curie temperature near MPB versus the end member tolerance factor (t). The mechanism of higher T{sub C} in BGSPT system was also proposed.

Jiang Yihang; Qin Baoquan; Yue Xi; Zhao Yi; Jiang Yuzhi; Xiao Dingquan; Zhu Jianguo [College of Materials Science and Engineering, Sichuan University, Chengdu 610064 (China)

2008-04-01

308

Research Note Reliability of Pb(Mg,Nb)O3Pb(Zr,Ti)O3 multilayer ceramic piezoelectric actuators by Weibull method  

Microsoft Academic Search

Expected lifetime and reliability of multilayer ceramic actuators were considered. 5 5 5m m 3 sized multilayer ceramic actuators with 60 ceramic sheet layers embedded internal electrodes were selected in this experimental analysis. Specially selected rectified AC bias was applied to the multilayer ceramic actuators to remove heating during charging and discharging process. Sixteen sets of multilayer ceramic

Jung-Hyuk Koh; Tae-geun Kim

309

Can Whiskers Grow on Bulk Lead-Free Solder?  

NASA Astrophysics Data System (ADS)

Many possible mechanisms for whisker growth exist, each possible in various scenarios investigated in the literature. This contribution addresses the importance of residual mechanical stress in a solder alloy for providing some of the energy necessary to drive possible whisker growth. We investigate the indentations made on bulk lead-free solder (Sn3.5Ag) to introduce various levels of residual energy associated with localized residual stresses. We confirm that localized residual stresses, in the absence of a thin-film geometry, significant oxide thickness, and interdiffusional stresses from intermetallic Cu-Sn compounds, do not result in the formation of whiskers in bulk Sn3.5Ag. Thus, the combination of stresses associated with thin films (either thermal misfit, plating, or chemical) and the oxidation of Sn at the surface is likely required for continuous whisker growth.

Nychka, John A.; Li, Yan; Yang, Fuqian; Chen, Rong

2008-01-01

310

Doping effects of CuO additives on the properties of low-temperature-sintered PMnN-PZT-based piezoelectric ceramics and their applications on surface acoustic wave devices.  

PubMed

To develop the anisotropic ceramic substrate with low sintering temperature for surface acoustic wave (SAW) applications, the low cost and feasible material with moderate piezoelectric properties, good dielectric properties, and higher Curie temperature were explored. The piezoelectric ceramics with compositions of Pb[(Mn(1/3)Nb(2/3))(0.06-) (Zr(0.52)Ti(0.48))0.94] O(3) (PMnN-PZT) + 0.5 wt.% PbO + x wt.% CuO (0.05 = x = 0.3) had been prepared by the conventional mixed-oxides method. CuO dopants were used as the sintering aid to improve the bulk density under low sintering temperature (i.e., 980-1040 degrees C). The phase structures, microstructures, frequency behavior of dielectric properties (up to 50 MHz), piezoelectric properties, ferroelectric properties, and temperature stability with the amount of CuO additive were systematically investigated. Experimental results showed that the sintering temperature could be lowered down to 1020 degrees C and still keep reasonably good piezoelectric activity (i.e., high electromechanical coupling factor (k(p)), (k(t)) and dielectric and ferroelectric properties. The preferable composition, obtained at x = 0.1, presented the values of the electromechanical coupling factor (k(p)) (k(t)), mechanical quality factor (Q(m)), piezoelectric charge constant (d(33)), dielectric constant, dielectric loss, temperature coefficient of resonant frequency (TCF(B)), and Curie point (T(c)) of 0.54, 0.48, 850, 238 pc/N, 1450, 0.0023, 1.1 kV/mm, 26 coul/cm(2), -150 ppm/ degrees C, and 348 degrees C. Using this developed low-temperature-sintered material to make the piezoelectric substrate, the SAW filter was fabricated and its properties were measured. Results showed that this device possessed very high value of k(2)(7.13%) with a good TCF (-40.15 ppm/ degrees C), and a surface wave velocity (V(P)) of 2196 m/s. PMID:19411224

Tsai, Cheng-Che; Chu, Sheng-Yuan; Lu, Chun-Hsien

2009-03-01

311

High Power Characteristics of Piezoelectric Ceramics in Pb(Mn1/3Nb2/3)O3 PbTiO3 PbZrO3 System  

NASA Astrophysics Data System (ADS)

As one of high power characteristics of the piezoelectricceramics in Pb(Mn1/3Nb2/3)O3 PbTiO3 PbZrO3system, the limit vibration velocity (vmax), is defined as thevibration velocity that generate the fixed temperature rise wasevaluated. From this system, a new material with a highervmax of 0.79 m/s which is 1.7 times larger than conventionalPb(Mn1/3Sb2/3)O3 PbTiO3 PbZrO3 system wasfound. By using this new material, piezoelectric transformers weremade and the output electric power (P) of the transformers weremeasured at RL=(?Cd2)-1 [load resistance (RL), resonant angular frequency (?), output damping capacitance (Cd2)] and at other fixed resistances. The P of the piezoelectric transformer was measured on this condition, however, measured values of P were smaller than that of the conventional material. In order to clarify this phenomenon, an equivalent circuit including stray capacitance (Cf) of the load circuit was proposed. Simulation results by using this equivalent circuit showed that; 1. The load resistance giving the maximum output power decreases, as Cf increases. 2. The maximum output power decreases, as Cf increases. 3. When Cd2 of the piezoelectric transformer is small, the effect of Cf on the piezoelectric transformer becomes large. Therefore, a high dielectric constant (?) is a required characteristicof the piezoelectric ceramic materials for use in the piezoelectrictransformer, except for the usually high vmax and highelectromechanical coupling coefficient (K).

Ise, Osamu; Satoh, Kaoru; Mamiya, Yoichi

1999-09-01

312

Electron microscopy study of ferroelectric domains and microstructural defects in Bi and Zn-modified Pb(Ni1\\/3Nb2\\/3)O3-PbZrO3-PbTiO3 piezoelectric ceramics  

Microsoft Academic Search

Ferroelectric domain configurations and microstructural defects in the Bi- and Zn-modified Pb(Ni1\\/3Nb2\\/3)O3-PbZrO3-PbTiO3 piezoelectric ceramics were investigated by transmission electron microscopy (TEM) and selected area electron diffraction. In the samples with tetragonal symmetry, labyrinthic domain configurations with 90deg a-c domains were observed besides the herringbone-like configuration, parallel band-shaped and\\/or wedge-shaped domains. Polar nanodomains with local random contrast were observed in the

X. H. Zhu; Y. Song; J. M. Zhu; S. H. Zhou; Z. G. Liu

2009-01-01

313

DIELECTRIC AND PIEZOELECTRIC CHARACTERISTICS OF 0.07Pb (Mn1\\/3Nb2\\/3) O3 ?0.10Pb (Ni1\\/3Nb2\\/3) O3? 0.83Pb(Zr0.48Ti0.52) O3 CERAMICS ACCORDING TO THE HEATING RATE  

Microsoft Academic Search

In this study, in order to develop the composition ceramics for low loss multilayer piezoelectric actuator, 0.07Pb (Mn1\\/3Nb2\\/3) O3 ?0.10Pb (Ni1\\/3Nb2\\/3) O3? 0.83Pb(Zr0.48Ti0.52) O3 (abbreviated as PMN-PNN-PZT) ceramics were fabricated using Li2CO3, Bi2O3 and CuO as sintering aids and according to variation of heating rate. And also, their dielectric and piezoelectric properties were investigated. At the heating rate of 700C\\/h

YUHYONG LEE; SANGHO LEE; JUHYUN YOO; INSUNG KIM; JAESUNG SONG

2008-01-01

314

Piezoelectric properties of 0.5(PbNi 1\\/3Nb 2\\/3)O 30.5Pb(Zr 0.32Ti 0.68)O 3 ceramics prepared by solid state reaction and mechanochemical activation-assisted method  

Microsoft Academic Search

0.5(PbNi1\\/3Nb2\\/3)O30.5Pb(Zr0.32Ti0.68)O3 (PNNPZT) ceramics were successfully prepared from a mechanochemical activation-assisted method (MAAM), which skips the calcination step(s) at an intermediate temperature which is otherwise required for solid state reaction. A detailed investigation has been carried out on the structural and piezoelectric properties of these samples. Improvement in piezoelectric properties was observed in PNNPZT ceramics processed by mechanochemical activation-assisted method. The

Sandeep Mahajan; Chandra Prakash; O. P. Thakur

2009-01-01

315

Preparation and characterization of novel piezoelectric and pyroelectric polymer electrets  

Microsoft Academic Search

The preparation and characterization of novel piezoelectric and pyroelectric electrets is discussed with respect to their electret properties. Charged heterogeneous electrets, like closed-cell microporous polypropylene (pp) foams and `soft-hard' fluoropolymer hybrids are shown to yield large quasi-static and dynamic piezoelectric responses, indistinguishable from true piezoelectricity. Piezoelectric coefficients comparable to that of ceramic counterparts have been achieved. For the investigation of

R. Schwodiauer; G. S. Neugschwandtner; K. Schrattbauer; M. Lindner; M. Vieytes; S. Bauer-Gogonea; S. Bauer

2000-01-01

316

Piezoelectric transducers, state of research  

Microsoft Academic Search

Methods for preparing, treating and sintering powders to be used in the production of ceramic elements (coprecipitation, isostatic compression, sintering under shock loading) are reviewed. Faults inherent in a piezoelectric ceramic element are outlined. Perovskite type compounds, analogous to PbTiO3, which are strongly anisotropic and have a very low k31 coupling factor; lead compounds which are strongly anisotropic and give

L. Eyraud; P. Eyraud; F. Bauer

1984-01-01

317

Hydrostatic piezoelectric property of composite PbTiO3-P(VDF\\/TeFE) for hydrophone applications  

Microsoft Academic Search

In order to improve hydrostatic piezoelectric sensitivity of flexible piezoelectric composites, Lead Titanate (PbTiO3) piezoelectric ceramics is incorporated because of its greater piezoelectric anisotropy. The composites are prepared by embedding ceramic PbTiO3 particles in a copolymer matrix poly(vinylidene fluoride\\/tetrafluoroethylene) (P(VDF\\/TeFE)). The preparation of these composites and their dielectric and hydrostatic piezoelectric properties are reported in this paper. Their hydrophone applications

Xiaoping Zou; Liangying Zhang; Xi Yao; Likun Wang; Fuxue Zhang

1996-01-01

318

Structure, microstructure and dielectric properties of 100- x(Bi0.5Na0.5)TiO3- x[SrTiO3] composites ceramics  

NASA Astrophysics Data System (ADS)

In this paper, lead-free 100- x(Bi0.5Na0.5)TiO3- x[SrTiO3] composites ceramics with (0? x?9) were synthesized by the solid-state reaction method. Their structure, dielectric, ferroelectric and piezoelectric properties were investigated. X-ray diffraction patterns, Rietveld refinement data and Raman spectra revealed that the SrTiO3 cubic structure was completely diffused into the (Bi0.5Na0.5)TiO3 lattice with rhombohedral structure. The scanning electron microscopy images showed change in grain morphology from rectangular-like to quasi-spherical grain with increase in SrTiO3 content. The dielectric permittivity increases, the Curie temperature decreases and the peaks become broaden with raise of SrTiO3 content. Ferroelectric and piezoelectric properties of these composites ceramics showed degenerated behavior with increase of SrTiO3.

Parija, B.; Rout, S. K.; Cavalcante, L. S.; Simes, A. Z.; Panigrahi, S.; Longo, E.; Batista, N. C.

2012-11-01

319

Failure analysis of lead-free solder joints for flip chip on board  

Microsoft Academic Search

With the great environmental concern, lead-free solders gradually replace lead-based solders in electronic packages. However, the relatively short history of lead-free solders makes their reliability database inadequate. In other words, there is an urgent need to establish the reliability information of lead-free solders. In this study, a failure analysis is conducted to investigate the reliability of lead free solders. The

Fu-Ming Tzu; Long-Sun Chao; Jung-Hua Chou

2007-01-01

320

Parameter identification method for piezoelectric shunt damping  

NASA Astrophysics Data System (ADS)

Piezoelectric shunt damping is a method to reduce structural vibration by shunting a piezoelectric element with an electrical circuit. This paper proposes a method to identify the physical parameters that are required to design piezoelectric shunt damping systems. Employing self-sensing actuator methodology, the proposed method requires no additional sensor or actuator other than a simple bridge circuit. The parameters can be identified from a transfer function simply by linear least squares method. To demonstrate the validity of the proposed method, the shunt damping of the steel plate with the piezoelectric ceramic is performed based on the identified parameters.

Takagi, Kentaro; Nagase, Kenji; Oshima, Kazuhiko; Hayakawa, Yoshikazu; Luo, Zhi-Wei

2004-02-01

321

Modeling Material Properties of Lead-Free Solder Alloys  

NASA Astrophysics Data System (ADS)

A full set of physical and thermophysical properties for lead-free solder (LFS) alloys have been calculated, including liquidus/solidus temperatures, fraction solid, density, coefficient of thermal expansion, thermal conductivity, Youngs modulus, viscosity, and liquid surface tension, all as a function of composition and temperature (extending into the liquid state). The results have been extensively validated against data available in the literature. A detailed comparison of the properties of two LFS alloys Sn-20In-2.8Ag and Sn-5.5Zn-4.5In-3.5Bi with Sn-37Pb has been made to show the utility and need for calculations that cover a wide range of properties, including the need to consider the effect of nonequilibrium cooling. The modeling of many of these properties follows well-established procedures previously used in JMatPro software for a range of structural alloys. This paper describes an additional procedure for the calculation of the liquid surface tension for multicomponent systems, based on the Butler equation. Future software developments are reviewed, including the addition of mechanical properties, but the present calculations can already make a useful contribution to the selection of appropriate new LFS alloys.

Guo, Zhanli; Saunders, Nigel; Miodownik, Peter; Schill, Jean-Philippe

2008-01-01

322

Microstructure and piezoelectric properties of 0.95(Na{sub 0.5}K{sub 0.5})NbO{sub 3}-0.05BaTiO{sub 3} ceramics  

SciTech Connect

For 0.95(Na{sub 0.5}K{sub 0.5})NbO{sub 3}-0.05BaTiO{sub 3} (0.95NKN-0.05BT) ceramics sintered at 1040-1075 deg. C, abnormal grain growth occurred but the grain size decreased when the sintering temperature exceeded 1075 deg. C. The dielectric constant ({epsilon}{sub 3}{sup T}/{epsilon}{sub 3}), electromechanical coupling factor (k{sub p}), and piezoelectric constant (d{sub 33}) were considerably increased with increasing relative density and grain size. Evaporation of Na{sub 2}O deteriorated the piezoelectric properties by decreasing the resistivity. To minimize Na{sub 2}O evaporation, specimens were muffled with 0.95NKN-0.05BT powders during the sintering. Improved piezoelectric properties of d{sub 33}=225 pC/N, k{sub p}=36%, and {epsilon}{sub 3}{sup T}/{epsilon}{sub 3}=1058 were obtained for specimen sintered at 1060 deg. C for 2 h with muffling.

Park, Hwi-Yeol; Ahn, Cheol-Woo; Song, Hyun-Cheol; Lee, Jong-Heun; Nahm, Sahn; Uchino, Kenji; Lee, Hyeung-Gyu; Lee, Hwack-Joo [Department of Materials Science and Engineering, Korea University, 1-5 Ka, Anam-Dong, Sungbud-Ku, Seoul 136-701 (Korea, Republic of); International Center for Actuators and Transducers, Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Korea Electronics Technology Institute, 68 Yatap-dong, Bundang-gu, Soeongnam-si, Gyeonggi-do 463-816 (Korea, Republic of); New Materials Evaluation Center, Korea Research Institute of Standards and Science, Daeduk Science Town, Taejon 305-600 (Korea, Republic of)

2006-08-07

323

Piezoelectric transducers, state of research  

NASA Astrophysics Data System (ADS)

Methods for preparing, treating and sintering powders to be used in the production of ceramic elements (coprecipitation, isostatic compression, sintering under shock loading) are reviewed. Faults inherent in a piezoelectric ceramic element are outlined. Perovskite type compounds, analogous to PbTiO3, which are strongly anisotropic and have a very low k31 coupling factor; lead compounds which are strongly anisotropic and give strongly attenuated ceramic elements; PVDF type polymers; electrostrictive materials; composite materials; and polar glass materials and electrets are described. Techniques for metallizing elements to improve the adhesive power of the electrodes and contacts; and adhesives and glues used for manufacturing transducers and composites are considered.

Eyraud, L.; Eyraud, P.; Bauer, F.

1984-06-01

324

Study of Lead Free Ferroelectric Films for New Solar Cells  

NASA Astrophysics Data System (ADS)

We report on the deposition by a sol-gel process of Ba0.8Sr0.2TiO3 and Ba0.9Sr0.1TiO3 films on platinum coated silicon substrates. X-Ray diffraction patterns show that the films are (111) preferentially oriented. The surface morphology is smooth, without cracks and the grain size is about 50 nm as determined by AFM and SEM. The dielectric constant measured from 102 to 106 Hz decreases slightly and is around 400 at 104 Hz. The losses are constant in a first approximation for a 1.5 ?m thick BST(80/20) film with a value of 0.03 at 10 kHz. The existence of an hysteresis cycle attests that the films, whatever their thickness, are in a ferroelectric state. Pyroelectric coefficients have been determined and the best figure of merit obtained on BST(90/10) at 293 K and 10 kHz is of 149 ?C/m3/K. The best dielectric and pyroelectric properties (tg? = 0.006 at 1 MHz, tunability = 30%, ? = 340 ?C/m2/K) were obtained on the 400 nm BST(90/10) film. Work is in progress to characterize the piezoelectric and photovoltaic properties of our BST films.

Fasquelle, D.; Mascot, M.; Carru, J. C.; Hikam, M.; Iriani, Y.; Soegijono, B.

2009-09-01

325

Study of Lead Free Ferroelectric Films for New Solar Cells  

SciTech Connect

We report on the deposition by a sol-gel process of Ba{sub 0.8}Sr{sub 0.2}TiO{sub 3} and Ba{sub 0.9}Sr{sub 0.1}TiO{sub 3} films on platinum coated silicon substrates. X-Ray diffraction patterns show that the films are (111) preferentially oriented. The surface morphology is smooth, without cracks and the grain size is about 50 nm as determined by AFM and SEM. The dielectric constant measured from 10{sup 2} to 10{sup 6} Hz decreases slightly and is around 400 at 10{sup 4} Hz. The losses are constant in a first approximation for a 1.5 {mu}m thick BST(80/20) film with a value of 0.03 at 10 kHz. The existence of an hysteresis cycle attests that the films, whatever their thickness, are in a ferroelectric state. Pyroelectric coefficients have been determined and the best figure of merit obtained on BST(90/10) at 293 K and 10 kHz is of 149 {mu}C/m{sup 3}/K. The best dielectric and pyroelectric properties (tg{delta} = 0.006 at 1 MHz, tunability = 30%, {gamma} = 340 {mu}C/m{sup 2}/K) were obtained on the 400 nm BST(90/10) film. Work is in progress to characterize the piezoelectric and photovoltaic properties of our BST films.

Fasquelle, D.; Mascot, M.; Carru, J. C. [LEMCEL, Universite du Littoral Cote d'Opale, 50 rue F. Buisson, BP717-62228-Calais-France (France); Hikam, M.; Iriani, Y.; Soegijono, B. [Department of Physics, Faculty of Mathematics and Sciences, University of Indonesia, Depok 16424 Indonesia (Indonesia)

2009-09-14

326

Piezoelectricity Demo  

NSDL National Science Digital Library

This lesson plan from the Oregon Museum of Science and Industry explores the history of piezoelectricity, with hands-on examples of how itâs used, models of why it happens, and how it is applied in nanotechnology. Pressing on the piezoelectric buzzer in the background causes a current to flow and the neon bulb in the foreground to glow.

2012-03-13

327

Investigation of electromigration behavior in lead-free flip chip solder bumps  

NASA Astrophysics Data System (ADS)

Packaging technology has also evolved over time in an effort to keep pace with the demanding requirements. Wirebond and flip chip packaging technologies have become extremely versatile and ubiquitous in catering to myriad applications due to their inherent potential. This research is restricted strictly to flip chip technology. This technology incorporates a process in which the bare chip is turned upside down, i.e., active face down, and is bonded through the I/O to the substrate, hence called flip chip. A solder interconnect that provides electrical connection between the chip and substrate is bumped on a processed silicon wafer prior to dicing for die-attach. The assembly is then reflow-soldered followed by the underfill process to provide the required encapsulation. The demand for smaller and lighter products has increased the number of I/Os without increasing the package sizes, thereby drastically reducing the size of the flip chip solder bumps and their pitch. Reliability assessment and verification of these devices has gained tremendous importance due to their shrinking size. To add to the complexity, changing material sets that are results of recently enacted lead-free solder legislations have raised some compatibility issues that are already being researched. In addition to materials and process related flip chip challenges such as solder-flux compatibility, Coefficient of Thermal Expansion (CTE) mismatch, underfill-flux compatibility and thermal management, flip chip packages are vulnerable to a comparatively newer challenge, namely electromigration observed in solder bumps. It is interesting to note that electromigration has come to the forefront of challenges only recently. It has been exacerbated by the reduction in bump cross-section due to the seemingly continuous shrinking in package size over time. The focus of this research was to understand the overall electromigration behavior in lead-free (SnAg) flip chip solder bumps. The objectives of the research were to comprehend the physics of failure mechanism in electromigration for lead-free solder bumps assembled in a flip chip ceramic package having thick copper under bump metallization and to estimate the unknown critical material parameters from Black's equation that describe failure due to electromigration. In addition, the intent was to verify the 'use condition reliability' by extrapolation from experimental conditions. The methodology adopted for this research was comprised of accelerated electromigration tests on SnAg flip chip solder bumps assembled on ceramic substrate with a thick copper under bump metallization. The experimental approach was comprised of elaborate measurement of the temperature of each sample by separate metallization resistance exhibiting positive resistance characteristics to overcome the variation in Joule heating. After conducting the constant current experiments and analyzing the failed samples, it was found that the primary electromigration failure mode observed was the dissolution of the thick copper under bump metallization in the solder, leading to a change in resistance. The lifetime data obtained from different experiments was solved simultaneously using a multiple regression approach to yield the unknown Black's equation parameters of current density exponent and activation energy. In addition to the implementation of a systematic failure analysis and data analysis procedure, it was also deduced that thermomigration due to the temperature gradient across the chip does impact the overall electromigration behavior. This research and the obtained results were significant in bridging the gap for an overall understanding of this critical failure mode observed in flip chip solder bumps. The measurement of each individual sample temperature instead of an average temperature enabled an accurate analysis for predicting the 'use condition reliability' of a comparable product. The obtained results and the conclusions can be used as potential inputs in future designs and newer generations of flip chip devices that might undergo

Kalkundri, Kaustubh Jayant

328

Synthesis of lead-free (K, Na)(Nb, Ta)O3 nanopowders using a sol-gel process.  

PubMed

Lead-free (K0.5Na0.5)(Nb0.7Ta0.3)O3 piezoelectric material was successfully synthesized via a sol-gel process. Crystalline (K0.5Na0.5)(Nb0.7Ta0.3)O3 nanopowders were obtained after heat treatment at 700 degrees C. The particle size was estimated to be 87nm +/- 23 nm. The transmission electron microscopy images showed that individual nanoparticles were single crystalline and had a pseudo-cubic structure with a lattice parameter of -3.96 angstroms. Both X-ray diffraction and scanning electron microscopy studies consistently showed that the crystallization of the (K0.5Na0.5)(Nb0.7Ta0.3)O3 occurred slightly above 500 degrees C. The samples have an appropriate stoichiometry as found via energy dispersive X-ray spectroscopy. The demonstration of the synthesis of (K0.5Na0.5)(Nb0.7Ta0.3)O3 via a sol-gel process as presented in this paper can provide an important foundation for the development of a synthetic route towards (K0.5Na0.5)(Nb0.7Ta0.3)O3 doped with various other elements for high performance piezoelectric devices. PMID:22849167

Rajesh, Dodla; Kim, Seungwook; Jeong, Jinhoo; Nahm, Sahn; Kim, Woong

2012-04-01

329

Piezoelectric characteristics of low temperature sintering Pb(Ni 1\\/3 Nb 2\\/3 )O 3 Pb(Zr 1\\/2 Ti 1\\/2 )O 3 ceramics as a function of Pb(Mn 1\\/3 Sb 2\\/3 )O 3 substitution  

Microsoft Academic Search

In this study, in order to develop the composition ceramics for multilayer ceramic for ultrasonic nozzle and ultrasonic actuator\\u000a application, Pb(Mn1\\/3Sb2\\/3)O3 (abbreviated as PMS) substituted Pb(Ni1\\/3Nb2\\/3)O3Pb(Zr,Ti)O3 (abbreviated as PNN-PZT) ceramics were fabricated using two-stage calcinations method and Li2CO3, Na2CO3 and ZnO as sintering aids, and their piezoelectric and dielectric characteristics were investigated. With the increase of\\u000a the amount of PMS

Sangho Lee; Juhyun Yoo; Insung Kim; Jaesung Song

2009-01-01

330

Piezoelectric and dielectric characteristics of low-temperature-sintering Pb(Mg 1\\/2 W 1\\/2 )O 3 Pb(Ni 1\\/3 Nb 2\\/3 )O 3 Pb(Zr,Ti)O 3 ceramics according to the amount of PNN substitution  

Microsoft Academic Search

In this study, in order to develop low-temperature-sintering ceramics for multilayer piezoelectric actuator, Pb(Mg1\\/2W1\\/2)O3Pb(Ni1\\/3Nb2\\/3)O3Pb(Zr,Ti)O3 (abbreviated as PMWPNNPZT) ceramics were fabricated using Li2CO3 and CaCO3 as sintering aids and their dielectric and piezoelectric properties were investigated with the amount of Pb(Ni1\\/3Nb2\\/3)O3 (abbreviated as PNN) substitution. PMWPNNPZT composition ceramics could be sintered up to 870C by adding sintering aids.\\u000a At the sintering

Yeongho Jeong; Kyungjin Yoo; Juhyun Yoo

2009-01-01

331

Dielectric and piezoelectric properties of <001> fiber-textured 0.675Pb(Mg1/3Nb2/3)O3-0.325PbTiO3 ceramics  

NASA Astrophysics Data System (ADS)

The 0.675Pb(Mg1/3Nb2/3)O3-0.325PbTiO3 (PMN-32.5PT) ceramic composition (with 1 wt. % excess PbO) was fiber textured in the <001> direction by the templated grain growth process using 5 vol % oriented {001}-BaTiO3 platelet crystals as the templates. The templated ceramics annealed at 1150 C for 5 h attained texture fractions as high as 0.9. The fiber-textured samples showed an increase in the piezoelectric, electromechanical coupling, and compliance coefficients when poled and measured in the <001>-textured direction. The low drive field (<5 kV/cm) d33 coefficients in the <001>, measured directly from unipolar strain-field measurements, were ~1150 pC/N. This d33 coefficient is 1.2-1.5 times greater than randomly oriented samples. The poled ?max and Vrt for a 0.9-textured PMN-32.5PT ceramic were 21 500 and 2450, respectively. Factors limiting further property improvements are discussed.

Sabolsky, Edward M.; Trolier-McKinstry, Susan; Messing, Gary L.

2003-04-01

332

Novel lead-free Sn-Cu-xBi nanosolders by chemical reduction method.  

PubMed

With environmental concerns on the toxicity of lead, investigations on lead-free solders become crucial. Studies on lowering process temperature of lead-free solders are required, because the melting points of lead-free solders are higher than original SnPb solders. Melting points of binary solders could be decreased by addition another materials. In this study, Sn-Cu-xBi lead-free nanoparticles were synthesized with precisely controlled size and composition by chemical precipitation method. Effects of different precursor concentration and surfactant addition were discussed. The influence of different amounts of Bi in the SnCu-based nano-particles was also probed. PMID:19441388

Huang, Po-Chun; Duh, Jenq-Gong

2009-02-01

333

The pyroelectric behavior of lead free ferroelectric ceramics in thermally stimulated depolarization current measurements  

NASA Astrophysics Data System (ADS)

The present paper shows a detailed analysis on the thermally stimulated processes in barium modified SrBi2Nb2O9 ferroelectric bi-layered perovskite, which is one of the most promising candidates for non-volatile random access memory applications because of its excellent fatigue-resistant properties. A numerical method is used to separate the real pyroelectric current from the other thermally stimulated processes. A discharge due to the space-charge injected during the poling process, the pyroelectric response, and a conductive process are discussed in a wide temperature range from ferroelectric to paraelectric phase. The pyroelectric response is separated from the other components to evaluate the polarization behavior and some pyroelectric parameters. The remanent polarization, the pyroelectric coefficient, and the merit figure are evaluated, which show good results.

Gonzlez-Abreu, Y.; Peliz-Barranco, A.; Garcia-Wong, A. C.; Guerra, J. D. S.

2012-06-01

334

Piezoelectric Film.  

ERIC Educational Resources Information Center

|Presents activities that utilize piezoelectric film to familiarize students with fundamental principles of electricity. Describes classroom projects involving chemical sensors, microbalances, microphones, switches, infrared sensors, and power generation. (MDH)|

Garrison, Steve

1992-01-01

335

Large piezoelectric effect in Pb-free Ba(Ti,Sn)O3-x(Ba,Ca)TiO3 ceramics  

NASA Astrophysics Data System (ADS)

We designed a Pb-free pseudo-binary system, Ba(Sn0.12Ti0.88)O3-x(Ba0.7Ca0.3)O3 (BTS-xBCT), characterized by a phase boundary starting from a tricritical triple point of a paraelectric cubic phase, ferroelectric rhombohedral, and tetragonal phases. The optimal composition BTS-30BCT exhibits a high piezoelectric coefficient d33 ~ 530 pC/N at room temperature. In view of the recent report of high piezoelectricity in another Pb-free system BZT-BCT (Liu and Ren, Phys. Rev. Lett. 103, 257602 (2009)), which possesses a similar tricritical triple point in the phase diagram, it seems that forming a suitable phase boundary starting from a tricritical triple point could be an effective way to develop high-performance Pb-free piezoelectrics.

Xue, Dezhen; Zhou, Yumei; Bao, Huixin; Gao, Jinghui; Zhou, Chao; Ren, Xiaobing

2011-09-01

336

FOREWORD: Focus on innovation in ceramics research in East Asia Focus on innovation in ceramics research in East Asia  

NASA Astrophysics Data System (ADS)

Ceramics, as broadly defined, include all materials other than organic substances and metals, either crystalline or amorphous. They have been used by humans since early history and have contributed considerably to improving the quality of our life. In most cases, however, high-temperature treatment is necessary to prepare ceramics. This burdens the environment and there is therefore a great need for new ceramics processing methods. Recent technologically advanced ceramics are often composed of nanocrystallites, which have great potential for innovation in terms of exploring practical applications of nanomaterials and, consequently, reducing the environmental load. The ceramics industry had long flourished in Asia, particularly in East Asia, and even today, this region is leading the development of related materials. In line with these traditions, Japanese and Korean ceramics societies have been co-sponsoring seminars on ceramics since the 1980s. Having become more international in scope and context, a series of these seminars is now known as the International Japan-Korea Seminar on Ceramics. This focus issue contains eight key articles presented at the 26th International Japan-Korea Seminar on Ceramics held on 24-26 November 2010 at the Tsukuba International Congress Center. In particular, Fabbri et al review electrode materials for protonic solid-oxide fuel cells, and Kamiya et al outline the present situation and future prospects for transparent transistors, particularly those based on amorphous In-Ga-Zn-O films. Eitel et al discuss the progress in engineering high-strain lead-free piezoelectric ceramics. Kim and Kumar review a simple processing method for producing porous ceramics using polysiloxane precursors, Kamiya and Iijima focus on surface modification and characterization of nanomaterials, and Wan et al briefly review the strategy of reducing lattice thermal conductivity of thermoelectric materials and propose new materials for thermoelectric devices. Aubert et al introduce a novel technique of synthesizing composite nanomaterials and Cross and coworkers characterize Pb(Zr,Ti)O3 (PZT) ferroelectric thin films co-doped with Bi and Fe to enhance PZT capacitor ferroelectric properties. These articles are closely related to the global environmental load and energy issues that require solutions in modern ceramics technology. We hope that this focus issue will help advance not only ceramics-related but also other fields of materials science.

Kato, Akio; Hishita, Shunichi; Osada, Minoru; Haneda, Hajime

2010-10-01

337

Highly piezoelectric Biocompatible and Soft Composite Fibers  

NASA Astrophysics Data System (ADS)

We report the fabrication of highly piezoelectric biocompatible soft fibers containing Barium Titanate (BT) ferroelectric ceramic particles dispersed in electrospun poly lactic acid (PLA). These fibers form mats that have two orders of magnitude larger piezoelectric constant per weight than single crystal barium titanate films. We demonstrate that the observed super-piezoelectricity results from the electrospinning induced polar alignment of the ferroelectric particles and the increased surface area compared to single crystal films. Due to the biocompatibility of PLA that encases the ferroelectric particles, these mats can be applied even in biological applications such as bio-sensors, artificial muscles and energy harvesting devices.

Jakli, Antal; Morvan, Jason; Buyuktanir, Ebru; West, John

2012-02-01

338

Highly piezoelectric biocompatible and soft composite fibers  

NASA Astrophysics Data System (ADS)

We report the fabrication of highly piezoelectric biocompatible soft fibers containing barium titanate ferroelectric ceramic particles dispersed in electrospun poly lactic acid (PLA). These fibers form mats that have two orders of magnitude larger piezoelectric constant per weight than single crystal barium titanate films. We propose that the observed apparent piezoelectricity results from the electrospinning induced polar alignment of the ferroelectric particles that pole the fibers similar to ferroelectret polymer foams that are poled by corona discharge. Due to the biocompatibility of PLA that encases the ferroelectric particles, these mats can be used in biological applications such as bio-sensors, artificial muscles, and energy harvesting devices.

Morvan, J.; Buyuktanir, E.; West, J. L.; Jkli, A.

2012-02-01

339

Analytically\\/experimentally evaluating the response of cylindrical piezoelectric material systems subjected to thermal loads  

Microsoft Academic Search

An electromechanical elasticity solution is presented to evaluate the response of a piezoelectric linear motor at cryogenic temperatures. This model incorporates the pronounced coupling which occurs in these materials between temperature and piezoelectric strain coefficients. Results from experimental tests are presented for ceramic piezoelectric flat specimens to determine the linear and nonlinear properties required in the model; including thermal expansion

Mike A. Stam; Donny P. Wang; Gregory P. Carman

1995-01-01

340

Stress analyses of a smart composite pipe joint integrated with piezoelectric composite layers under torsion loading  

Microsoft Academic Search

In order to improve the joint failure strength, an adhesively bonded smart composite pipe joint system has been developed by integrating electromechanical coupling piezoelectric layers with the connection coupler. It has been validated that the integrated piezoelectric ceramic layers can smartly reduce stress concentration in the adhesive layer bond-line under bending or axial tension loads. In this study, piezoelectric particle\\/fiber

Jinquan Cheng; Guoqiang Li

2008-01-01

341

Piezoelectric and electrostrictive materials for transducer applications, volume 1  

Microsoft Academic Search

The topics covered under the program are reported under three major topic areas: Piezoelectric and Related Composites, Electrostriction, Phenomenology and Properties of Conventional Ceramic, and Piezoelectrics. A brief report is also given of related studies required to support and supplement work on the three major areas, under the title Associated Programs. The year has seen major personnel changes at the

L. E. Cross; R. E. Newnham; G. R. Barsch; J. V. Biggers

1988-01-01

342

Piezoelectric piggy-back microactuator for hard disk drive  

Microsoft Academic Search

A new piezoelectric piggy-back microactuator for high density hard disk drives was designed and fabricated to achieve more accurate positioning of the magnetic head and increasing servo bandwidth. The microactuator is made of stiff piezoelectric ceramic material to actuate the slider on which the head-element is formed. It is designed to amplify the actuating displacement. The basic mechanical performance of

Yoshikazu Soeno; Sliinji Ichikawa; Takamitsu Tsuna; Yoshikazu Sato; Isamu Sato

1999-01-01

343

3K-1 Integrated and Flexible Piezoelectric Ultrasonic Transducers  

Microsoft Academic Search

Thick (>40 mum) ceramic films as piezoelectric and ultrasonic transducers (UTs) have been successfully deposited on metallic and non-metallic substrates by a spray technique. In the film fabrication a composite consisting of piezoelectric powders well mixed with solution of high dielectric constant is directly sprayed onto the substrate. It is then dried, fired or annealed by heat. Multiple coating is

M. Kobayashi; C.-K. Jen

2006-01-01

344

A buck-boost bidirectional converter to drive piezoelectric actuators  

Microsoft Academic Search

The present work deals with the development and control of a converter to drive piezoelectric actuators. In order to maximize the field in the piezoelectric ceramic important voltages are needed. To fulfill such requirements with a limited input voltage a bidirectional buck-boost converter is proposed. The converter is controlled by means of a sliding mode control strategy. The converter is

Oriol Gomis-Bellmunt; Daniel Montesinos-Miracle; Samuel Galceran-Arellano; A. Sudria-Andreu

2007-01-01

345

Effective moduli of granular and layered composites with piezoelectric constituents  

Microsoft Academic Search

The effective elastic and dielectric moduli of a composite made from piezoelectric materials are examined, with particular emphasis on applications to unpoled piezoelectric ceramics and layered materials. Explicit formulae for the effective moduli and coupling of a layered material are derived. A self-consistent estimate of the moduli of an isotropic polycrystal is obtained through an effective medium approximation (EMA), which

Tamara Olson; Marco Avellaneda

1993-01-01

346

A new type of linear piezoelectric stepper motor  

Microsoft Academic Search

A new type of linear piezoelectric stepper motor combining the piezoelectric effect with the electrorheological (ER) effect as studied. The ER effect occurred in fluids that can make a transition from the liquid state to a weak solid state reversibly controlled by an electric field. The driving device of a piezomotor consists of a bilayer piezoactuator using PMN-PNN-PZT ceramics, an

Shuxiang Dong; Longtu Li; Zhilun Gui; Tieying Zhou; Xiao-wen Zhang

1995-01-01

347

Displacement properties of RAINBOW and THUNDER piezoelectric actuators  

Microsoft Academic Search

The electromechanical displacement properties of two recently developed piezoelectric actuators, referred to as RAINBOW and THUNDER, have been measured and compared. The actuators evaluated in this investigation are fabricated from 2.54 cm diameter PZT-5H and PZT-5A piezoelectric ceramic disks and are produced with the same total device thicknesses and ceramic-to-metal thickness ratios. For the compositions tested, the RAINBOW devices are

Stephanie A. Wise

1998-01-01

348

A Cement-Based Piezoelectric Sensor for Civil Engineering Structure  

Microsoft Academic Search

A new aggregate-like sensor using piezoelectric ceramic as sensing element was designed, fabricated and tested. The sensor\\u000a was made by bonding together two cuboids of hardened cement paste with a commercially available piezoelectric ceramic plate\\u000a in between, which is the sensing element. A new adhesive was developed during the fabrication of the sensor. The sensor was\\u000a tested on its basic

B. Shen; X. Yang; Z. Li

2006-01-01

349

Piezoelectric Properties of Vanadium-Substituted Strontium Bismuth Niobate  

Microsoft Academic Search

Vanadium-substituted strontium bismuth niobate, SrBi2Nb1.95V0.05O9 (SBNV), ceramics were synthesized by a low-temperature process, and the detailed piezoelectric properties of the SBNV ceramics were characterized. Dense SBNV ceramics were obtained at a sintering temperature of 950C, which is 200C lower than that for nonsubstituted (SBN) ceramics. With the substitution of vanadium cations for niobium the ferroelectric D-E hysteresis loops were observed

Rintaro Aoyagi; Shinya Inai; Yuji Hiruma; Tadashi Takenaka

2005-01-01

350

Recent progress in science and technology of flexible piezoelectric composite in Japan  

Microsoft Academic Search

Theoretical equations for dielectric piezoelectric and elastic properties of 0-3 composites are derived as a general solution based on a modified cube model using the equations from series and parallel models. Dielectric and piezoelectric properties of flexible composites consisting of a polymer and a single ceramic powder or ceramic powder mixture of two average particle sizes are investigated as a

Hisao Banno

1990-01-01

351

A-site effects on the dielectric and the piezoelectric properties of (Na0.50+ x K 0.50-x)(Nb0.55Ta0.45)O3 ceramics  

NASA Astrophysics Data System (ADS)

(Na0.5+ x K0.5- x )(Nb0.55Ta0.45)O3 (NKNT) ceramics prepared by using a solid state process were investigated for various A-site ratios between Na and K at 0 ? x ? 0.05 to determine the morphotropic phase boundary (MPB). Within the compositional range tested, X-ray diffraction patterns showed NKNT perovskite peaks with no apparent secondary peaks. Scanning electron microscope images showed little difference among microstructures composed of cube-like grains. The piezoelectric coefficient ( d 33) was enhanced up to 310 pC/N at x = 0.03 from 262 pC/N at x = 0 and then decreased with further increases in x while the polymorphic phase transition (PPT) temperature ( T O-T ) located around room temperature varied little with x. As a result, the increase that occurred in d 33 was mainly due to the MPB effects with the MPB composition of the NKNT ceramics at (Na0.53K0.47).

Lee, J. H.; Ryu, G. H.; Cho, J. H.; Song, T. K.; Kim, M. H.; Park, T. G.; Do, D.; Kim, S. S.; Sung, Y. S.; Baik, S.

2012-01-01

352

Piezoelectric properties of MnO 2 doped low temperature sintering Pb(Mn 1\\/3 Nb 2\\/3 )O 3 Pb(Ni 1\\/3 Nb 2\\/3 )O 3 Pb(Zr 0.50 Ti 0.50 )O 3 ceramics  

Microsoft Academic Search

In this study, in order to develop the composition ceramics for low loss and low temperature sintering multilayer piezoelectric\\u000a actuator, Pb(Mn1\\/3Nb2\\/3)O3Pb(Ni1\\/3Nb2\\/3)O3Pb(Zr0.50Ti0.50)O3 (abbreviated as PMN-PNN-PZT) ceramics were fabricated using Li2CO3 and Na2CO3 as sintering aids, and their piezoelectric and dielectric characteristics were investigated according to the amount of MnO2 addition. At the 0.2wt% MnO2 doped specimen sintered at 900C, density and

Juhyun Yoo; Sangho Lee

2009-01-01

353

Processing, texture quality, and piezoelectric properties of <001>C textured (1-x)Pb(Mg1/3Nb2/3)TiO3 - xPbTiO3 ceramics  

NASA Astrophysics Data System (ADS)

This paper describes the link between texture quality and electromechanical properties for <001>C textured, 0.03(Na1/2Bi1/2)TiO3 - 0.97[0.715Pb(Mg1/3Nb2/3)TiO3 - 0.285PbTiO3] (0.03NBT-0.97[PMN-28.5PT]) ceramics with and without Mn-doping. Here, the subscript C denotes pseudocubic indices. Textured ceramics were prepared by templated grain growth of PMN-25PT on platelet-shaped 0.4(Na1/2Bi1/2)TiO3-0.6PbTiO3 (NBT-0.6PT) templates. Texture fractions of f = 0.92 (for undoped (1-x)Pb(Mg1/3Nb2/3)TiO3-xPbTiO3 (PMN-PT)) and f = 0.49 (for Mn-doped PMN-PT) were determined by fitting 002C XRD pole figures to the March-Dollase model, which was modified to account for symmetry-related 200C and 020C reflections. Using resonance methods, the elastic constants cij, sij, piezoelectric constants dij, eij, gij, hij, dielectric constants ?ij, and coupling coefficients kij of textured PMN-PT ceramics were characterized. It was found that the properties of textured PMN-PT approach the single crystal values along the texture axis (<001>C, also the poling axis), but not in transverse directions. In particular, the elastic compliance sE11 (perpendicular to <001>C) approaches an average of the single crystal sE11 and sE11(45) coefficients, resulting in anomalous -sE12/sE11 ratios of - 0.01 and 0.04 in pure and Mn-doped textured PMN-PT, respectively. The 33-mode properties as measured by resonance-antiresonance methods were d33 = 852 pC/N, k33 = 0.83, ?33 = 3500, and mechanical quality factor Qm = 94 for undoped textured ceramics and d33 = 515, k33 = 0.76, V33 = 2200, and Qm = 714 for Mn-doped textured ceramics.

Poterala, Stephen F.; Trolier-McKinstry, Susan; Meyer, Richard J.; Messing, Gary L.

2011-07-01

354

Multilayer piezoelectric devices based on PZT  

Microsoft Academic Search

A PZT 53\\/47 was obtained by a modified chemical route. Small-particle-size powders were allowed to obtain high solid content, non-aqueous slips with Newtonian behaviour. The use of both the tape-casting technique and the common multilayer ceramic fabrication process led to a high-density multilayer ceramic body without cracks or delaminations, and a homogeneous microstructure. The architecture of multilayer piezoelectrics has an

E. Nieto; J. F. Fernandez; C. Moure; P. Duran

1996-01-01

355

Simulation of uniaxial tensile properties for lead-free solders with modified Anand model  

Microsoft Academic Search

The uniaxial tensile inelastic deformation behavior for three types of lead-free solders, Sn3Ag0.5Cu, Sn3.5Ag and Sn0.7Cu, were simulated by a unified viscoplastic constitutive model, the Anand model. To obtain the material parameters for the Anand model, a series of constant true strain rate and temperature tests were conducted on three types of lead-free solders at various strain rates from 110?4s?1

Ning Bai; Xu Chen; Hong Gao

2009-01-01

356

Preparation of ultra-fine copper powder and its lead-free conductive thick film  

Microsoft Academic Search

In this paper, non-agglomerated monodispersed ultra-fine copper metallic powders have been synthesized with chemical reduction method. Fine lead-free glass powders were also prepared by solid synthesis process. Thick film paste prepared by above-mentioned copper metallic powders and lead-free glass powders was applied as conductive paste of MLCC. Mixture of glass and zinc oxide give the thick film a high adhesion

Songping Wu

2007-01-01

357

Investigation of the stress-strain curves of lead-free solder alloy  

Microsoft Academic Search

In this paper, a new methodology to extract the elasto-plastic properties of lead-free solder materials from an instrumented sharp indentation loading curve has been proposed using dimensional analysis and finite element computation. The nano indenter XP technology is used to test samples of lead-free eutectic SnAgCu solder alloys to obtain a load-displacement curve, which can be used to calculate its

Niu Xiaoyan; Ma Yong; Li Zhigang; Shu Xuefeng; Yang Guitong

2008-01-01

358

Reduction of lead free solder aging effects using doped SAC alloys  

Microsoft Academic Search

The microstructure, mechanical response, and failure behavior of lead free solder joints in electronic assemblies are constantly evolving when exposed to isothermal aging and\\/or thermal cycling environments. In our prior work on aging effects, we have demonstrated that large degradations occur in the material properties (stiffness and strength) and creep behavior of Sn-Ag-Cu (SAC) lead free solders during aging. These

Zijie Cai; Yifei Zhang; Jeffrey C. Suhling; Pradeep Lall; R. Wayne Johnson; Michael J. Bozack

2010-01-01

359

Wettability of electroless Ni in the under bump metallurgy with lead free solder  

Microsoft Academic Search

This study investigates the wettability of several lead-free solders, including Sn, Sn?Ag, and Sn?Bi, on electroless Ni (EN)\\u000a with various phosphorus content. The role of phosphorus on solder wettability is studied. Microstructure evolution in the\\u000a lead-free solder\\/EN joint is investigated with the aid of electron probe microanalyzer (EPMA) to relate metallurgical reactions\\u000a between the solder and the EN. The SN

Bi-Lian Young; Jenq-Gong Duh; Bi-Shiou Chiou

2001-01-01

360

The effect of lead free soldering on formation of black pad failure  

Microsoft Academic Search

By this time usable solder alloys for lead-free soldering had already been developed. NEMI (National Electronics Manufacturing Initiative) recommends Sn\\/3.9Ag\\/0.6Cu (0.2%) solder alloy for reflow soldering instead of leaded solder alloys, due to its excellent mechanical properties and other good parameters. The next step is the choosing of suitable pad finish for lead-free soldering. In the age of fine pitch

Oliver Krammer

2005-01-01

361

Rate-dependent properties of Sn-Ag-Cu based lead free solder joints  

Microsoft Academic Search

The increasing demand for portable electronics has led to the shrinking in size of electronic components and solder joint dimensions. The industry also made a transition towards the adoption of lead-free solder alloys, commonly based around the Sn-Ag-Cu alloys. As knowledge of the processes and operational reliability of these lead-free solder joints (used especially in advanced packages) is limited, it

Yong'An Su; Long Bin Tan; V. B. C. Tan; Tong Yan Tee

2009-01-01

362

Lead-free chip scale packages: assembly and drop test reliability  

Microsoft Academic Search

Three underfill options compatible with lead-free assembly have been evaluated: capillary underfill, fluxing underfill, and corner bond underfill. Chip scale packages (CSPs) with eutectic Sn\\/Pb solder were used for control samples. Without underfill, lead-free and Sn\\/Pb eutectic drop test results were comparable. Capillary flow underfills, dispensed and cured after reflow, are commonly used in CSP assembly with eutectic Sn\\/Pb solder.

Yueli Liu; Guoyun Tian; Shyam Gale; R. Wayne Johnson; Lawrence Crane

2006-01-01

363

Effects of PCB design variations on bend and ATC performance of lead-free solder joints  

Microsoft Academic Search

Sn-Ag-Cu (SAC) solder alloys, such as Sn-3.0Ag-0.5 Cu (SAC305) are the popular choices of lead-free solders replacing SnPb solders. However, SAC solders are more brittle in nature due to high stiffness and excessive intermetallic compounds growth at the solder joint to pad interface. This leads to higher risks in solder joints failures. Memory module type lead-free BGA packages are constantly

Hongtao Ma; Kuo-Chuan Liu; Tae-Kyu Lee; Dong Hyun Kim

2010-01-01

364

Reliability of lead free solders joints and manufacturability during the SMT process  

Microsoft Academic Search

In systematic investigations the failure behaviour of lead free solder joints for different solder alloys as well as substrate metallization was analyzed. The emphasis of the investigations was the optimization of the processing parameters for the printing of different lead-free no-clean solder pastes in the standard pitches from 1.27 mm to 0.4 mm. Furthermore, evidence was provided of the aging-determined

T. Herzog

2004-01-01

365

Reliability assessment of flip-chip assemblies with lead-free solder joints  

Microsoft Academic Search

Due to environmental awareness, and the health hazards involved in using lead in solders, large efforts to develop lead-free soldering have been made in recent years. Sn-Ag alloys are expected to be one of the best candidate lead-free solders. Furthermore, from a reliability viewpoint, there has been interest in improved thermal fatigue resistance of solder interconnects. In this study, two

A. Schubert; R. Dudek; H. Walter; E. Jung; A. Gollhardt; B. Michel; H. Reichl

2002-01-01

366

Reliability study of surface mount printed circuit board assemblies with lead-free solder joints  

Microsoft Academic Search

Purpose The purpose of this paper is to evaluate the lead-free solder joint reliability of a variety of surface mount components assembled onto printed circuit boards (PCBs) under a number of different tests. Design\\/methodology\\/approach Lead-free solder with a composition of Sn96.5-Ag3.0-Cu0.5 was used in a surface mount reflow process. Different types of surface mount dummy components with a

Jeffery C. C. Lo; B. F. Jia; Z. Liu; J. Zhu; S. W. Ricky Lee

2008-01-01

367

The Influence of Elevated Temperature Aging on Reliability of Lead Free Solder Joints  

Microsoft Academic Search

The microstructure, mechanical response, and failure behavior of lead free solder joints in electronic assemblies are constantly evolving when exposed to isothermal aging and\\/or thermal cycling environments. In our prior work on aging effects (Ma, et al., ECTC 2006), we demonstrated that the observed material behavior variations of SAC405 and SAC305 lead free solders during room temperature aging (25 degC)

Hongtao Ma; J. C. Suhling; Yifei Zhang; P. Lall; M. J. Bozack

2007-01-01

368

On piezoelectric super-helix actuators  

Microsoft Academic Search

Theoretical designs of piezoelectric ceramic helical and spiral actuators have existed for many years. The main reason these devices have not achieved widespread recognition and use is the perceived difficulty of processing such forms. These processing problems, covering both the material form itself and electrode placement, have been tackled and solved over recent years at the University of Birmingham. A

David H. Pearce; Anthony Hooley; Tim W. Button

2002-01-01

369

Microstructure of BaTiO3--Bi(Mg1/2Ti1/2)O3--BiFeO3 Piezoelectric Ceramics  

NASA Astrophysics Data System (ADS)

The dependence of the ferroelectric and piezoelectric properties of (1-x)(0.33BaTiO3--0.67BiFeO3)--xBi(Mg1/2Ti1/2)O3 (x = 0, 0.05, 0.10, and 0.15) on Bi(Mg1/2Ti1/2)O3 content x associated with microstructural changes is studied. From the behaviour of electric field-induced polarization and strain, polarization switching and depolarizing become easier as Bi(Mg1/2Ti1/2)O3 content x increases. Remanent polarization and dielectric constant decrease, while polarization saturation field increases with increasing x. Microstructural observation reveals that Bi(Mg1/2Ti1/2)O3 addition enhances the compositional fluctuation of BaTiO3/BiFeO3 ratio, which probably creates a nanometre-sized domain region with slightly BaTiO3-rich composition. Since this nanometre-sized domain may cause relatively large responses of polarization and strain to the applied electric field, an appropriate amount of Bi(Mg1/2Ti1/2)O3 enhances the electric field-induced strain, resulting in the largest piezoelectric response at x = 0.05. However, excessive Bi(Mg1/2Ti1/2)O3 degrades polarization and strain characteristics, because a number of Ba(Fe1-xMgx/2Tix/2)12O19 grains are created as a secondary phase and cause the segregation of excess bismuth oxide phases with low dielectric constant into the boundaries of the ferroelectric/piezoelectric grains.

Yabuta, Hisato; Shimada, Mikio; Watanabe, Takayuki; Hayashi, Jumpei; Kubota, Makoto; Miura, Kaoru; Fukui, Tetsuro; Fujii, Ichiro; Wada, Satoshi

2012-09-01

370

Raman imaging of grain growth mechanism in highly textured Pb(Mg{1{/}3}Nb{2{/}3})O{3}-PbTiO{3} piezoelectric ceramics*  

NASA Astrophysics Data System (ADS)

Pb(Mg{1 / 3}Nb{2 / 3})O{3}-PbTiO{3} solid solution ((1-x)PMN-xPT) tape cast ceramics have been prepared by homo-epitaxial templated grain growth (HTGG) using cubic 0.75PMN 0.25 PT single crystal seeds as template (a few wt%) and x = 0.35 nanoparticles for the ceramic matrix. Raman imaging studied representative medium and highly textured ceramics. On the base of a previous study which has shown that the Raman peak centre of gravity depends on the solid solution composition whereas peak intensity is correlated to the unit-cell distortion, Raman imaging shows that the final composition and structure is very close to that of the matrix.

Colomban, P.; Pham Thi, Mai

2005-06-01

371

Cymbal piezoelectric composite underwater acoustic transducer.  

PubMed

The working principle of Cymbal piezoelectric composite underwater acoustic transducer was studied in this paper. PZT-5A piezoelectric ceramic disk was used as piezoelectric phase and brass foil was used as end cap electrode of the Cymbal transducer. The silicon rubber was used as the insulated proof layer of the underwater acoustic transducer. The properties of this transducer used as hydrophone, such as operation frequency, free-field voltage receiving sensitivity and directivity, were investigated. Several kinds of prototype of this transducer were fabricated and the properties of this transducer used as hydrophone were tested. The results show that the properties of this transducer used as hydrophone depend on the dimensions of Cymbal transducer because the piezoelectric properties of this transducer are dependent on the dimensions of Cymbal transducer's end caps. The appropriate dimensions for getting higher free-field voltage receiving sensitivity with -184.7 dB were obtained. PMID:16793099

Li, Denghua; Wu, Min; Oyang, Peixi; Xu, Xiaofei

2006-06-06

372

Polar glass ceramics  

Microsoft Academic Search

Pyroelectric-piezoelecric glass ceramics of polar materials like Li2Si2O5, Ba2TiGe2O8, Ba2TiSi2O8, and Various compositions in the systems Li2O-B2O3, Li2O-SiO2-ZnO, Li2O-SiO2-B2O3 have been prepared by oriented recrystallization of the glasses under a strong temperature gradient, providing a simple inexpensive process for preparing piezoelectric and pyroelectric materials. High pyroelectric responses were observed in these glass-ceramics. Values of piezoelectric d33 coefficients, frequency constants, electromechanical

A. Halliyal; A. S. Bhalla; R. E. Newnham; L. E. Cross

1981-01-01

373

Electric field induced fracture mechanism and aging of piezoelectric behavior in Pb(MgNb)O 3Pb(ZrTi)O 3 multilayer ceramic actuators  

Microsoft Academic Search

Electrical aging and mechanical fracture behavior of 0.2(PbMg1\\/3Nb2\\/3O3)0.8(PbZr0.475Ti0.525O3) multilayer ceramic actuators have been investigated by applying both bipolar and unipolar voltages for unpoled and poled actuator, respectively. After 8.7107 cycles of 2kV\\/mm bipolar voltage, unpoled multilayer ceramic actuator had distorted shape of PE hysteresis loops. Effective electromechanical coupling coefficient keff of poled actuator was calculated by considering resonant frequency and

Jung-Hyuk Koh; Soon-Jong Jeong; Mun-Su Ha; Jae-Sung Song

2004-01-01

374

Piezoelectric Properties of Polycrystalline Lead Titanate Zirconate Compositions  

Microsoft Academic Search

Detailed data are given for the piezoelectric, elastic, and dielectric properties of lead titanate zirconate ceramic compositions near the rhombohedral-tetragonal phase boundary. These compositions have markedly higher electromechanical coupling factors, remanent ferroelectric charge, and coercive field, than ceramic barium titanate. Another interesting feature is a pronounced change in the free permittivity 33T by the poling process; this change is in

D. A. Berlincourt; C. Cmolik; H. Jaffe

1960-01-01

375

Dielectrophoretically structured piezoelectric composites with high aspect ratio piezoelectric particles inclusions  

NASA Astrophysics Data System (ADS)

Piezoelectric composites were prepared by dielectrophoretic alignment of high aspect ratio piezoelectric particles in a thermosetting polymer matrix. A high level of alignment was achieved in the cured composite from a resin containing randomly oriented high aspect ratio particles. Upon application of an electric field during curing of the resin, the particles were found to rotate with their long axes in the direction of the electric field, before coalescing to form chains. The dielectric and piezoelectric properties of the structured composites are well described by an analytical model for composites containing particles arranged into chains. The influence of degree of rotation and aspect ratio of the individual particles as well as their spacing is described with this model. The results correlate with the experimental values for both permittivity and piezoelectric constants in the poling direction. Dielectric and piezoelectric properties were significantly improved with respect to randomly dispersed piezoelectric ceramic powder-polymer composites and the maximum g33 was shifted to a lower volume fraction. The results could have implications for development of dielectric and piezoelectric (nano-)fiber composites for dielectrics such as embedded capcitors, as well as piezoelectrics for sensing and energy harvesting applications.

van den Ende, D. A.; van Kempen, S. E.; Wu, X.; Groen, W. A.; Randall, C. A.; van der Zwaag, S.

2012-06-01

376

Generation of Tin(II) Oxide Crystals on Lead-Free Solder Joints in Deionized Water  

NASA Astrophysics Data System (ADS)

The effect of the anode and cathode on the electrochemical corrosion behavior of lead-free Sn-Ag-Cu and Sn-Ag-Cu-Bi solder joints in deionized water was investigated. Corrosion studies indicate that SnO crystals were generated on the surfaces of all lead-free solder joints. The constituents of the lead-free solder alloys, such as Ag, Cu, and Bi, did not affect the corrosion reaction significantly. In contrast to lead-free solders, PbO x was formed on the surface of the traditional 63Sn-37Pb solder joint in deionized water. A cathode, such as Au or Cu, was necessary for the electrochemical corrosion reaction of solders to occur. The corrosion reaction rate decreased with reduction of the cathode area. The formation mechanism of SnO crystals was essentially a galvanic cell reaction. The anodic reaction of Sn in the lead-free solder joints occurred through solvation by water molecules to form hydrated cations. In the cathodic reaction, oxygen dissolved in the deionized water captures electrons and is deoxidized to hydroxyl at the Au or Cu cathode. By diffusion, the anodic reaction product Sn2+ and the cathodic reaction product OH- meet to form Sn(OH)2, some of which can dehydrate to form more stable SnO xH2O crystals on the surface of the solder joints. In addition, thermodynamic analysis confirms that the Sn corrosion reaction could occur spontaneously.

Chang, Hong; Chen, Hongtao; Li, Mingyu; Wang, Ling; Fu, Yonggao

2009-10-01

377

Synthesis of piezoelectric materials by ultrasonic assisted hydrothermal method  

NASA Astrophysics Data System (ADS)

Hydrothermal method enables to synthesize high quality piezoelectric materials. To shorten the reaction time and to get higher quality materials, we propose an ultrasonic irradiation to the solution during the hydrothermal method. We named it ultrasonic assisted hydrothermal method (UAHTM). We have synthesized lead-free piezoelectric material and PZT thin film and the effect of UAHTM have been confirmed. In this study, we tried to improve UAHTM. First, to generate powerful and stable ultrasonic irradiation at high temperature on UAHTM, we developed a new transducer using LiNbO3 single crystal. Second, to prevent contamination to the materials, A Teflon cover on the tip of transducer was attached.

Isobe, Gaku; Ageba, Ryo; Maeda, Takafumi; Bornmann, Peter; Hemsel, Tobias; Morita, Takeshi

2012-05-01

378

Mechanical properties of SnPb and lead-free solders at high rates of strain  

NASA Astrophysics Data System (ADS)

The mechanical properties of 63% Sn-37% Pb and lead-free solders have been measured at high strain rates (500-3000 s-1) using a split Hopkinson pressure bar. The solders were produced by quenching in water from the melt, to give the phase structure associated with rapid cooling. Measurements were made at -40 C, room temperature and +60 C. The Sn-Pb solder was strongly strain rate and temperature dependent, whereas the lead-free solders showed only a weak dependence on these parameters. All of the materials behaved elasto-plastically until a plateau stress of circa 200 MPa. An unexpected, and possibly important, feature of the lead-free solders was the division of the specimens into two groups with different strengths at low temperatures.

Siviour, C. R.; Walley, S. M.; Proud, W. G.; Field, J. E.

2005-11-01

379

Intermediate strain rate dependant mechanical properties for lead-free solders  

Microsoft Academic Search

Lead-free solders have strain rate dependent mechanical properties. In this work we report the elastic modulus and yield strength of several lead-free solder alloys at different strain rates. They are SnAgCu (with Ag 1 to 4% and Cu at 0.5%, namely SAC105, SAC205, SAC305 and SAC405), SAC-X (X=In, Ni and Bi), SnCu, SnCu-X and SnAg alloys. The intermediate strain rate

Luhua Xu; Kok Ee Tan; J. H. L. Pang

2010-01-01

380

Isothermal cyclic bend fatigue test method for lead free solder joints  

Microsoft Academic Search

Isothermal three-point and four-point cyclic bend fatigue test method have been developed for Sn-Ag-Cu solder joints. Reported bend tests from the literature were conducted at room temperature (25degC) and there is lack of data for lead-free solder joints. In this study, VQFN assembly with Sn-Ag-Cu lead-free solder was tested under three-point and four-point cyclic bending load at room temperature (25degC)

John H. L. Pang; Fa-Xing Che

2006-01-01

381

Piezoelectric Effect  

NSDL National Science Digital Library

In this activity, by the Concord Consortium's Molecular Literacy project, students explore the piezoelectric effect, which is the conversion between electricity and mechanical motion. The model used in this activity shows this conversion and users can manipulate the model to change the voltage and observe changes to a crystal. The activity itself is a java-based interactive resource built upon the free, open source Molecular Workbench software. In these activities, students are allowed to explore at their own pace in a digital environment full of demonstrations, illustrations, and models they can manipulate. In addition to the activity, visitors will find an overview of the activity and central and key concepts.

2008-10-23

382

Transmission electron microscopy investigation of the high temperature BiScO3-PbTiO3 piezoelectric ceramic system  

Microsoft Academic Search

Recently, a perovskite solid-solution ((1-x)BiScO3-(x)PbTiO3) with superior electromechanical properties than PbZrO3-PbTiO3 (PZT) ceramics has been discovered. The system has a morphotropic phase boundary (MPB) between ferroelectric rhombohedral (R) and tetragonal (T) symmetries similar to PZT but the underlying domain structures and some aspects of the crystal chemistry remain to be elucidated. Therefore, transmission electron microscopy has been used to study

C. A. Randall; R. E. Eitel; T. R. Shrout; D. I. Woodward; I. M. Reaney

2003-01-01

383

Lead-free solder materials for sustainable development of green electronics in China  

Microsoft Academic Search

Building recycle society is the key to ensure the sustainable development of China. The green electronics, including the advanced electronic packaging technology, play a most important role to promote the development of recycle society. In this paper, the development and trend of the green electronic industry, technology and laws in China and other countries are reviewed. New lead-free solder alloys

Jusheng Ma; Guohai Chen

2005-01-01

384

Effects of aging on the stress-strain and creep behaviors of lead free solders  

Microsoft Academic Search

Solder materials demonstrate evolving micro structure and mechanical behavior that changes significantly with environmental exposures such as isothermal aging and thermal cycling. These aging effects are greatly exacerbated at higher temperatures typical of thermal cycling qualification tests for harsh environment electronic packaging. In the current study, mechanical measurements of thermal aging effects and material behavior evolution of lead free solders

Hongtao Ma; Jeffrey C. Suhling; Pradeep Lall; Michael J. Bozack

2006-01-01

385

Effects of Physical Aging on the Stress-Strain and Creep Behaviors of Lead Free Solders  

Microsoft Academic Search

Solder materials demonstrate evolving properties that change significantly with environmental exposures such as isothermal aging and thermal cycling. Such physical aging effects are exacerbated at higher temperatures typical of thermal cycling qualification tests for harsh environment electronic packaging. In this work, measurements of thermal aging induced material behavior evolution have been performed for tin-lead and lead free solders. Extreme care

Hongtao Ma; J. C. Suhling; P. Lall; M. J. Bozack

2006-01-01

386

Development and characterization of AuCu seal ring for lead free packaging of MEMS devices  

Microsoft Academic Search

Seal rings are developed for packaging of circular openings of sensors and the fluidic flow based Micro Electro Mechanical Systems. Lead free technique based on isothermal solidification is used in this course of study. Thick film Au and high purity Cu substrates have been used during the development practice. Indium is used as the interlayer metal. Interconnections of high thermal

R. P. Sharma; P. K. Khanna; D. Kumar

2010-01-01

387

How to Identify Lead-Free Certification Marks for Drinking Water System & Plumbing Materials - Presentation  

EPA Science Inventory

In 2011, Congress passed the ?Reduction of Lead in Drinking Water Act,? which effectively reduces the lead content allowed in material used for potable water plumbing. The Act, which will go into effect on January 4, 2014, changes the definition of ?lead-free? by reducing allowed...

388

A study of nanoparticles in SnAg based lead free solders  

Microsoft Academic Search

Co, Ni, Pt, Al, P, Cu, Zn, Ge, Ag, In, Sb or Au inclusions in SnAg based lead free solders were evaluated to study if these nanoparticles can reduce the growth of intermetallic compounds after four time reflow processes and thermal aging. Also, these nanoparticles were studied if they can reduce the frequency of occurrence of intermetallic compound fractures in

Masazumi Amagai

2008-01-01

389

Assembly challenges of high density large fine pitch lead-free flip chip package  

Microsoft Academic Search

Assembly challenges for a high density, high performance integrated circuit package have been studied with respect to leadfree solder, fine pitch, large die on an organic substrate. The stresses induced by the large die size, higher reflow temperature due to lead-free solder and the low solder standoff due to fine-pitch configuration has shown to affect the quality of the assembly

Ser Choong Chong; Yeow Meng Tan; Tai Chong Chai; Samuel Lim; Wai Yin Hnin; Chek Kweng Cheng

2006-01-01

390

Coarsening processes in the lead-free solder alloy AgCu: theoretical and experimental investigations  

Microsoft Academic Search

Experimental investigations show that the microstructure of solders changes over time. In order to estimate the reliability and the lifetime of microelectronic solder materials it is important to predict the rate of microstructural change. Starting with an experimentally based overview on nucleation, spinodal decomposition as well as subsequent phase growth as observed in (lead-free) microelectronic solder connections this paper concentrates

W. H. Muller; T. Bohme

2005-01-01

391

Identification of Mechanical Properties of Intermetallic Compounds on Lead Free Solder  

Microsoft Academic Search

In this paper, we present methods for obtaining mechanical properties of silicon substrates and two intermetallic compounds (IMC) formed at the interfaces between lead-free solders and the copper and between leadfree solders and nickel substrates. To determine the mechanical properties of the silicon substrate, 255 um (100) and 306 um (110) thick silicon wafers were adopted. With proper sensor locations

Iting Tsai; Li Jung Tai; S. F. Yen; T. H. Chuang; R. Lo; T. Ku; Enboa Wu

2005-01-01

392

Development of a lead free chip scale package for wireless applications  

Microsoft Academic Search

Chip scale packages have seen a growth of over two times in the last two years and are expected to have more demands in the booming telecommunications market. This rapid growth of chip scale packages combined with green packaging solutions has made the implementation of lead free solders for chip scale package applications inevitable. But the effect of various lead

Vaidyanathan Kripesh; Poi-Siong Teo; C. T. Tai; Gautham Vishwanadam; Yew Cheong Mui

2001-01-01

393

Study on thermal simulation technology for SMA in lead-free reflow soldering  

Microsoft Academic Search

The thermal mathematical model under intensive convection in lead-free reflow soldering process is constructed for surface mounted assemblies, and the heat conduction governing equation, initial condition and boundary condition are made. A thermal mathematical model of SMA is transformed into solid model which can be analyzed by the thermal analysis software FLOTHERM. Then by defining the reasonable boundary condition and

Wu Zhaohua; Zhou Dejian

2008-01-01

394

Rate dependence of bending fatigue failure characteristics of lead-free solder joint  

Microsoft Academic Search

This study concerns the failure mechanism of a lead-free SAC305 solder joint under the isothermal bending fatigue condition. For this, series of bending fatigue tests are carried out with the variations of bending displacement and frequency, and FEM analysis is conducted to examine the relationship between mechanical behavior of a solder joint and fatigue life cycle. The results of this

Woong Ho Bang; Liang-Shan Chen; Choong-Un Kim; Tae-Kyu Lee; Kuo-Chuan Liu

2009-01-01

395

The impact of thermal cycling regime on the shear strength of lead-free solder joints  

Microsoft Academic Search

Purpose The purpose of this work is to undertake a comparison of accelerated test regimes for assessing the reliability of solder joints, in particular those made using lead-free solders. Design\\/methodology\\/approach Identical samples of 1206, 0805 and 0603 resistors were subjected to six different cycling regimes to investigate the effect of thermal excursions, ramp rates and temperature dwells. Findings

Milos Dusek; Martin Wickham; Christopher Hunt

2005-01-01

396

Impact reliability estimation of lead free solder joint with IMC layer  

Microsoft Academic Search

To secure the reliability of lead free solder is a critical issue for a chip-scale packaging process. While lots of researches on the solder reliability have been conducted by applying numerical simulation techniques, researches on IMC (intermetallic compound) are not intensively condoned due to its thin thickness, geometric irregularity and so on. However, the IMC layer which is generated during

Jong-Min Kim; Seung-Wan Woo; Yoon-Suk Chang; Young-Jin Kim; Jae-Boong Choi; Kum-Young Ji

2009-01-01

397

Effect of microstructure design on reliability of FBGA lead-free solder joints  

Microsoft Academic Search

In this paper, the fine pitch ball grid array (FBGA) assembly with lead free solder was tested under thermal cycling condition. Finite element modeling and simulation was conducted. The microstructure designs of via in pad of substrate and through hole (via) in PCB under the solder joint were simulated. The solder mask definition (SMD) and non-solder mask definition (NSMD) on

F. X. Che; J. E. Luan

2009-01-01

398

Effect of Ni Plating Thickness on Fatigue Failure of Lead-free Solder Joints  

Microsoft Academic Search

The purpose of this paper is to study the effect of plating thickness on fatigue failure of lead-free solder joints after thermal aging. Cyclic three-point bending tests were carried out and investigate the relationships between intermetallic compound (IMC) layer development and the fatigue life of solder joints. After the fatigue tests, cross- sections of solder joint were observed by scanning

M. Omiya; Takeshi Miyazaki; Hirotsugu Inoue; K. Kishimoto; M. Amagai

2006-01-01

399

Quality and reliability assurance by implementation of lead-free technology in electronic industry  

Microsoft Academic Search

For industrial implementation of lead-free materials are necessary important changes in process parameters (temperature, tolerances), auxiliary materials (fluxes, pastes) and manufacturing equipment. One of the most important problems of these changes is the warranty of good quality and reliability of electrical joints realized in new, environment-friendly technology. Especially for small electronic enterprises, it will be difficult to prove that the

Drozd Zdzislaw; Szwech Marcin; Bronowski Jaroslaw

2003-01-01

400

High thermal stability of piezoelectric properties in (Na0.5Bi0.5TiO3)x-(BaTiO3)y-(Na0.5K0.5NbO3)1-x-y ceramics  

NASA Astrophysics Data System (ADS)

We report the piezoelectric and ferroelectric properties of (Na0.5Bi0.5TiO3)x-(BaTiO3)y-(Na0.5K0.5NbO3)1-x-y ceramics for Na0.5K0.5NbO3 rich end of composition (x, y <= 0.04 mol. %). These compositions were found to exhibit significantly improved thermal stability of piezoresponse. Variation of dielectric constant as a function of temperature revealed that orthorhombic-tetragonal (To-t) and tetragonal-cubic (Tc) transition temperatures for these compositions were in the vicinity of 0 C and 330 C, respectively. Dynamic scaling and temperature dependent X-ray diffraction analysis were conducted. Results are discussed in terms of intrinsic and extrinsic contributions to the piezoelectric response explaining the temperature dependent behavior.

Gupta, Shashaank; Priya, Shashank

2013-01-01

401

Piezoelectric Properties of Bismuth Layer-Structured Ferroelectric Ceramics with a Preferred Orientation Processed by the Reactive Templated Grain Growth Method  

Microsoft Academic Search

Dense CaBi4Ti4O15 (CBT) and Na0.475Ca0.05Bi4.475Ti4O15 (NCBT) ceramics with a highly preferred {001} orientation were prepared by the reactive templated grain growth (RTGG) method. Plate-like Bi4Ti3O12 (BIT) particles were synthesized by a molten salt technique and used as the reactive template. The template particles were mixed with other oxide and carbonate powders and aligned by tape-casting. During the sintering, oriented CBT

Tsuguto Takeuchi; Toshihiko Tani; Yasuyoshi Saito

1999-01-01

402

Lead-free ferroelectric BaTiO 3 doped-(Na 0.5 Bi 0.5 )TiO 3 thin films processed by pulsed laser deposition technique  

NASA Astrophysics Data System (ADS)

MPB lead free BNT-BT 0.08 thin films were deposited on Pt/Si substrate, in optimized pulsed laser deposition conditions. Structural and morphological characteristics have been correlated with deposition process and target morphology. The BNT-BT 0.08 thin film exhibits a well-defined ferroelectric hysteresis loop at room temperature. The leakage current density in BNT-BT 0.08 thin film is relatively low. Local piezoelectric and ferroelectric responses in BNT-BT 0.08 thin films, were identified.

Dragoi, Cristina; Cernea, Marin; Trupina, Lucian

2011-09-01

403

Design and characterization of piezoelectric ultrasonic motors  

NASA Astrophysics Data System (ADS)

This thesis presents modeling and prototype fabrication and characterization of new types of piezoelectric ultrasonic micromotors. Our approach in designing these piezoelectric motors was: (i) to simplify the structure including the poling configuration of piezoelectric elements used in the stator and (ii) to reduce the number of components in order to decrease the cost and enhance the driving reliability. There are two different types of piezoelectric motors designed throughout this research. The first of these designs consists of a metal tube, on which two piezoelectric ceramic plates poled in thickness direction, were bonded. Two orthogonal bending modes of the hollow cylinder were superimposed resulting in a rotational vibration. Since the structure and poling configuration of the active piezoelectric elements used in the stator are simple, this motor structure is very suitable for miniaturization. Moreover, a single driving source can excite two bending modes at the same time, thus generate a wobble motion. Three types of prototypes are included in this design. The piezoelectric stator structure is the same for all. However, the dimensions of the motors are reduced by almost 50 percent. Starting with a 10 mm long stator, we reached to 4 mm in the last prototype. The initial diameter was 2.4 mm, which was reduced to 1.6 mm. In the final design, the rotor part of the motor was changed resulting in the reduction in the number of components. In terms of driving circuit, a single driving source was enough to run the motors and a conventional switching power supply type resonant L-C circuit was used. A simple motor structure with a simple driving circuit were combined successfully and fabricated inexpensively. The second design is a shear type piezoelectric linear motor. The behavior of a single rectangular piezoelectric shear plate was analyzed and after optimizing the dimensions and the mode characteristics, a prototype was fabricated. The prototype consists of one layer of ceramic and a brass teeth-like layer bonded on it. The displacement was amplified with the metal layer, the teeth of which were placed on the points of in-phase motion. The targeted application area is paper-feeding mechanism. In terms of application areas for the first design, a gas valve system and a micro vehicle were constructed. In addition, a new optical coherence tomography endoscope by utilizing the piezoelectric micromotor was designed. Finally, the prototype motor was integrated inside the camera of a cell phone to drive the zoom mechanism.

Yener, Serra

404

Consideration of Impedance Matching Techniques for Efficient Piezoelectric Energy Harvesting  

Microsoft Academic Search

This study investigates multiple levels of impedance-matching methods for piezoelectric energy harvesting in order to enhance the conversion of mechanical to electrical energy. First, the transduction rate was improved by using a high piezoelectric voltage constant (g) ceramic material having a magnitude of g33 = 40 times 10-3 V m\\/N. Second, a transducer structure, cymbal, was optimized and fabricated to

Hyeoungwoo Kim; Shashank Priya; Harry Stephanou; Kenji Uchino

2007-01-01

405

Smart System Using New Piezoelectric Fiber with Metal Core  

NASA Astrophysics Data System (ADS)

A new piezoelectric ceramic fiber containing a metal core was produced by the extrusion method. The insertion of a metal core is significant because the fiber's strength can be supported by the metal core which also serves as an internal electrode. A new smart board was designed by mounting these piezoelectric fibers into the surface of a CFRP composite. This smart composite board was able to both detect, and suppress vibrations.

Shimojo, Yoshiro; Sato, Hiroshi; Takagi, Kiyoshi; Shan, Yue Jin; Imoto, Hideo; Nagamine, Masaru

406

Yoffe-type moving edge crack in a piezoelectric block  

Microsoft Academic Search

Summary We consider an anti-plane edge moving crack problem with the constant velocity in a piezoelectric ceramic block. The far-field anti-plane shear mechanical and in-plane electrical loads are applied to the piezoelectric block. It is expressed to a Fredholm integral equation of the second kind. Expressions for the dynamic field intensity factors and the dynamic energy release rate are obtained.

S. M. Kwon; K. Y. Lee

2002-01-01

407

Analysis of the electrically forced vibrations of piezoelectric mesa resonators  

NASA Astrophysics Data System (ADS)

We study the electrically forced thickness-shear and thickness-twist vibrations of stepped thickness piezoelectric plate mesa resonators made of polarized ceramics or 6-mm class crystals. A theoretical analysis based on the theory of piezoelectricity is performed, and an analytical solution is obtained using the trigonometric series. The electrical admittance, resonant frequencies, and mode shapes are calculated, and strong energy trapping of the modes is observed. Their dependence on the geometric parameters of the resonator is also examined.

He, Hui-Jing; Nie, Guo-Quan; Liu, Jin-Xi; Yang, Jia-Shi

2013-08-01

408

Absolute and relative fatigue life prediction methodology for virtual qualification and design enhancement of lead-free BGA  

Microsoft Academic Search

The semiconductor industry is driving toward lead-free solder due to environmental concern and legislation requirement. The industry has also concluded that SnAgCu solder alloy so far is the best lead-free alternative to SnPb solder. Therefore, most existing and new packages have to be tested and qualified using lead-free solder. One of the critical concerns is board level solder joint reliability

Hun Shen Ng; Tong Yan Tee; Kim Yong Goh; Jing-en Luan; Tommi Reinikainen; Esa Hussa; Arni Kujala

2005-01-01

409

FP5-CSG-IMECAT : Highlights of a EC funded Project on Lead-Free Materials and Assembly Development Technologie  

Microsoft Academic Search

The EC has financially supported a pan-European collaboration on the development of lead-free interconnection materials and use of these materials for electronic assembly in a wide variety of industrial applications. The project started in April 2002 and is now close to the end. For the lead-free interconnection materials the focus was on lead-free solders, as well as on adhesives. The

Bart Vandevelde; Jan Vanfleteren; Bjorn Vandecasteele; Mario Gonzalez; Petar Ratchev; Inge Schildermans; Geert Willems; Joachim Wiese; Hans-Werner Hagedorn; Dion Manessis; M. Mango; Jarmo Mttnen; Daniel Vanderstraeten; Eddy Blansaer; Frank Kriebel

410

Piezoelectric Properties of 0.2[Pb(Mg 1\\/3 Nb 2\\/3 )]-0.8[PbTiO 3 -PbZrO 3 ] Ceramics Sintered at a Low Temperature with the Aid of Li 2 O  

Microsoft Academic Search

The dielectric and piezoelectric properties of 0.2Pb(Mg1\\/3Nb2\\/3)O3-0.8Pb(Zr0.475Ti0.525)O3 (abbr. as PMNZT) ceramics were measured. Extremely low sintering temperatures of 950?C using liquid-phase sintering aid of Li2O is achieved which was very useful for multi-layered applications. X-ray study shows the splitting of rhombohedral (200) in pure PMNZT to (002) and (200) peaks in Li2O doped samples. 10 times higher dielectric constant was

Byung Moon Jin; Ill Won Kim; Jin Soo Kim; Dae Su Lee; Chang Won Ahn; Jeong Ho Kwon; Jae Shin Lee; Jae Sung Song; Soon Jong Jeong

2005-01-01

411

Lead free heterogeneous multilayers with giant magneto electric coupling for microelectronics/microelectromechanical systems applications  

NASA Astrophysics Data System (ADS)

Lead free magneto electrics with a strong sub resonant (broad frequency range) magneto electric coupling coefficient (MECC) is the goal of the day which can revolutionise the microelectronics and microelectromechanical systems (MEMS) industry. We report giant resonant MECC in lead free nanograined Barium Titanate-CoFe (Alloy)-Barium Titanate [BTO-CoFe-BTO] sandwiched thin films. The resonant MECC values obtained here are the highest values recorded in thin films/multilayers. Sub-resonant MECC values are quite comparable to the highest MECC reported in 2-2 layered structures. MECC got enhanced by two orders at a low frequency resonance. The results show the potential of these thin films for transducer, magnetic field assisted energy harvesters, switching devices, and storage applications. Some possible device integration techniques are also discussed.

Nair, Swapna S.; Pookat, Geetha; Saravanan, Venkata; Anantharaman, M. R.

2013-08-01

412

Giant electrocaloric effect in lead-free thin film of strontium bismuth tantalite  

NASA Astrophysics Data System (ADS)

Giant electrocaloric effect was observed in lead-free material for the first time. A demonstration of large electrocaloric effect in 200 nm sol-gel thin film SrBi2Ta2O9 is described here. The ferroelectric hysteresis loops and the film permittivity were measured. The extracted data characterized the electrocaloric temperature change, up to 4.93K in 12V (i.e., 0.41 K V-1) near the Curie point. It is concluded that the giant electrocaloric effect exists in lead-free materials, and a large family of layered perovskite oxides may exhibit analogical property. The absence of lead allows eco-friendly application and enhances compatibility with integrated circuit process in future applications.

Chen, Hao; Ren, Tian-Ling; Wu, Xiao-Ming; Yang, Yi; Liu, Li-Tian

2009-05-01

413

Recent developments in ceramic actuators  

NASA Astrophysics Data System (ADS)

In these several years, piezoelectric and electrostrictive materials have become key components in smart actuator/sensor systems such as precision positioners, miniature ultrasonic motors and adaptive mechanical dampers. This paper reviews recent developments of piezoelectric and related ceramic actuators with particular focus on the improvement of actuator materials, device designs and drive/control techniques of actuators. Developments will be compared among USA, Japan and Europe.

Uchino, Kenji

1998-04-01

414

Modified Anand constitutive model for lead-free solder Sn3.5Ag  

Microsoft Academic Search

An improved Anand constitutive model is proposed to describe the inelastic deformation of lead free solder Sn-3.5Ag used in solder joints of microelectronic packaging. The new model accurately predicted the overall trend of steady-state stress-strain behavior of the solder for the temperature range from 233 K to 398 K and the strain rate range from 0.005 s-1 to 0.1 s-1h0,

Xu Chen; Gang Chen; Masao Sakane

2004-01-01

415

Determination of tensile properties of lead-free solder joints using nanoindentation  

Microsoft Academic Search

In this work, determination of tensile properties using depth-sensing technique has been demonstrated. An empirical model has been used to extract tensile properties of bulk pure Sn and lead free solder joints using nanoindentation technique. New scheme is proposed based on the non-linear curve fitting analysis of indentation load-displacement data. Elastic modulus, yield strength, perfect plastic hardness and strain hardening

B. S. S. Chandra Rao; K. Y. Zeng; V. Kripesh

2010-01-01

416

Numerical Analysis on Stress and Strain in QFP Lead-Free Solder with Temperature Impact  

Microsoft Academic Search

To study the relation between the QFP lead-free solder stress and strain accumulation under the condition of the impact of temperature (-55C~125C), Visco-plastic finite element model based upon Anand constitutive equations is established to numerically analyze the interfacial stress of solder formed by three different kinds of solders to the same substrate FR-4. The results shows that the interface stress

Li Zhi; Zhao Mei-rong; You Min; Lu Wei-bin; Wang Yun-Tao

2009-01-01

417

Size and microstructure effects on the stress-strain behaviour of lead-free solder joints  

Microsoft Academic Search

The properties of lead-free solders such as Sn3.8Ag0.7Cu are less understood than traditional Sn-Pb solders, as well as the factors affecting these material properties. Therefore, the present paper focuses on determination of stress-strain properties for both small-scale solder joints and for bulk solder for three different strain rates. The paper also analyses the obtained experimental results, and compares material properties

Pradeep Hegde; David C. Whalley; Vadim V. Silberschmidt

2009-01-01

418

Printed circuit boards for lead-free soldering: materials and failure mechanisms  

Microsoft Academic Search

Purpose This paper aims to evaluate the influence of previous exposure to moisture on delamination and formation of CAF (conductive anodic filament) in printed circuit boards used for lead-free soldering. Design\\/methodology\\/approach The moisture absorption and desorption characteristics of printed circuit boards were evaluated according to the IPC\\/JEDEC J-STD-020C standard for handling of moisture sensitive components. The CAF test

Per Johander; Per-Erik Tegehall; Abelrahim Ahmed Osman; Gran Wetter; Dag Andersson

2007-01-01

419

A study of lead-free BGA backward compatibility through solderability testing at component level  

Microsoft Academic Search

A study was conducted to assess the backward compatibility of two different lead-free BGA components using Jedec Solderability testing method (JESD22-B102D). The test was conducted at component level. The two components tested were 2929mm Thermally Enhanced PBGA (TePBGA-II) and 3535mm Tape BGA (TBGA) with SAC387 and Sn3.5Ag solder balls. Four units from each of the two component types were used

Eu Poh Leng; Wong Tzu Ling; Nowshad Amin; Ibrahim Ahmad

2008-01-01

420

Reflow ageing influences and wettability effects of immersion tin final finishes with lead-free solder  

Microsoft Academic Search

Purpose The purpose of this paper is to investigate the oxidation behaviour of an immersion tin final finish after multiple reflow ageing under air and nitrogen atmospheres and to study their influence on the wetting behaviour with lead-free solder. To design a model that describes the degradation of wetting behaviour after reflow-cycling of the immersion tin final finish. Design\\/methodology\\/approach

Thomas Hetschel; Klaus-Jrgen Wolter; Fritz Phillipp

2009-01-01

421

Rework Process Window and Microstructural Analysis for Lead-Free Mirrored Bga Design Points  

Microsoft Academic Search

Hot gas rework of BGAs with a mirrored BGA design configuration using SnAgCu based lead-free alloys is more challenging as compared to conventional SnPb techniques. Rework of BGAs using a conventional SnPb alloy system has historically required that mirrored BGA solder joints remain below the eutectic melt temperature of 183?C to avoid secondary (or partial) reflow of these mirrored solder

Matthew Kelly; Mitchell Ferrill; Polina Snugovsky; Rupen Trivedi; Gaby Dinca; Chris Achong; Zohreh Bagheri

422

Results of comparative reliability tests on lead-free solder alloys  

Microsoft Academic Search

The use of lead-free solder brings up concerns regarding the reliability of the new alloys to be used. In a European project (LEADFREE) SnAg, SnAgCu, SnAgCuSb, SnZn and SnPbAg have been tested in order to evaluate comparative data of the growth of cracks in solder joints. Reliability tests performed in other projects use accelerated tests proposed for tin-lead solders and

Giinter Grossmann; Giovanni Nicoletti; Ursin Solr

2002-01-01

423

Thermal and Mechanical Reliability Tests of Lead - free soldered SMT Joints  

Microsoft Academic Search

One of the main goals in development of electronics manufacturing technology, after implementation of EU Directive RoHS, is the reliability improvement of electronic interconnection systems. Investigations of lead-free technology for small producers of electronic equipment (SME's) were made in Warsaw University of Technology (WUT) in frame of GreenRoSE Project financed by EC. Achieved results of accelerated thermal and mechanical cycling

Z. Drozd; M. Szwech; R. Kisiel

2007-01-01

424

Shear Failure Analysis of Sub50 ?m Flip Chip Lead-free Solder Bumps  

Microsoft Academic Search

Sn-0.7Cu, Sn-3.5Ag, Sn-4Ag-0.5Cu lead-free solder bumps were produced by stencil printing of solder pastes on wafers having electroless Ni-P immersion Au (ENIG) under bump metallization (UBM). The diameter of the solder bumps was 4547 ?m. Shear tests were carried out to evaluate the bonding quality of the solder bumps after multiple reflows and thermal aging at 150C. The fracture surface,

Mingliang Huang

2007-01-01

425

Modeling of interfacial intermetallic compounds in the application of very fine lead-free solder interconnections  

Microsoft Academic Search

Intermetallic compounds (IMCs) are formed between lead-free solders and base metals during soldering processes. The morphology\\u000a as well as the amount of the IMCs, in particular the interfacial IMCs, are important to mechanical performance of the solder\\u000a joints in their service environment. This is especially the case in state-of-art ultrafine-pitch wafer-level packaging, in\\u000a which solder joints could become as small

Zhiheng Huang; Paul P. Conway; Rongshan Qin

2009-01-01

426

THERMOMECHANICAL ANALYSIS OF A CHIP SCALE PACKAGE (CSP) USING LEAD FREE AND LEAD CONTAINING SOLDER MATERIALS  

Microsoft Academic Search

This work is intended to provide a quantitative estimation of the accumulated inelastic strain of two different lead free solder alloys, namely, Sn3.5Ag and Sn3.8Ag0.5Cu. The eutectic Sn37Pb solder is also considered to establish a baseline. Thermomechanical stress and strain analysis was conducted on a Chip Scale Package (CSP). The solder joint fatigue was modeled for two typical temperature cycling

M. GONZALEZ; B. VANDEVELDE; E. BEYNE

427

Lead-free wafer level-chip scale package: assembly and reliability  

Microsoft Academic Search

This paper discusses the reliability testing results of a lead-free version of the micro SMD, National Semiconductor's Wafer Level-Chip Scale Package (WL-CSP). The micro SMD, a true wafer scale package has proven to be highly adaptable in the conventional assembly process, requiring no special considerations during the surface mount assembly operation. The current micro SMD utilizes standard Sn\\/Pb solder bumps

V. Patwardhan; N. Kelkar; L. Nguyen

2002-01-01

428

Nanoindentation on SnAgCu lead-free solder and analysis  

Microsoft Academic Search

To improve the measurement accuracy of hardness and modulus results of lead-free SnAgCu from nanoindentation experiments, evaluation of the creep effect on measured result and was reported. For SnAgCu solder in this study, it was found that penetration continues with a very long time and the penetration depth could increase extra 1000 nm when the load was held constant. Thus

Luhua Xu; J. H. L. Pang

2005-01-01

429

Nanoindentation on SnAgCu lead-free solder joints and analysis  

Microsoft Academic Search

The lead-free SnAgCu (SAC) solder joint on copper pad with organic solderability preservative (Cu-OSP) and electroless nickel\\u000a and immersion gold (ENIG) subjected to thermal testing leads to intermetallic growth. It causes corresponding reliability\\u000a concerns at the interface. Nanoindentation characterization on SnAgCu solder alloy, intermetallic compounds (IMCs), and the\\u000a substrates subjected to thermal aging is reported. The modulus and hardness of

Luhua Xu; John H. L. Pang

2006-01-01

430

Wetting behaviour of lead free solder on electroplated Ni and Ni-W alloy barrier film  

Microsoft Academic Search

In this work, electrodeposited Ni-W alloys were studied as barrier films between Cu substrate and lead free Sn3.8Ag0.7Cu (SAC387) solder. Wetting angle and spreading rate of SAC387 on Ni-W alloys with different tungsten contents were investigated and compared with that on Ni film deposited from Watt's bath. Ni-W alloy films of about 1.5 to 2.5 mum were deposited from ammonia-citrate

C. S. Chew; A. S. M. A. Haseeb; M. R. Johan

2009-01-01

431

Nanoindentation for measuring individual phase mechanical properties of lead free solder alloy  

Microsoft Academic Search

The elimination of lead from electronics due to its detrimental effects to environment and health is pushing component manufacturers\\u000a to consider lead free solder alloys as the substitute. Application of such alloys requires a better understanding of their\\u000a mechanical behavior at small volume size and at elevated temperatures. Such information is still lacking for both solder joints\\u000a and bulk materials.

Yong Sun; Jin Liang; Zhi-Hui Xu; Guofeng Wang; Xiaodong Li

2008-01-01

432

Wetting behaviour of lead free solder on electroplated Ni and Ni-W alloy barrier film  

Microsoft Academic Search

In this work, electrodeposited of Ni-W alloys were studied as barrier films between Cu substrate and lead free Sn3.8Ag0.7Cu (SAC387) solder. Wetting angle and spreading rate of SAC387 on Ni-W alloys with different tungsten contents were investigated and compared with that on Ni film deposited from Watt's bath. Ni-W alloy films of about 1.5 to 2.5 m were deposited from

C. S. Chew; A. S. M. A. Haseeb; M. R. Johan

2010-01-01

433

A Study of Lead-Free BGA Backward Compatibility Through Solderability Testing at Component Level  

Microsoft Academic Search

A study was conducted to assess the backward compatibility of three different lead-free BGA components using Jedec Solderability testing method (JESD22-B102D). The test was conducted at component level. The three components tested were 29??29 mm Thermally Enhanced PBGA (TePBGA-II) and 35??35mm Tape BGA (TBGA) with SAC387 and Sn3.5Ag solder balls, as well as 33??33 mm Flip Chip HiCTE BGA with

Eu Poh Leng; Wong Tzu Ling; N. Amin; I. Ahmad

2008-01-01

434

Development of SnZn lead-free solders bearing alloying elements  

Microsoft Academic Search

SnZn solder alloys have been considered as one of the more attractive lead-free solders since it can easily replace SnPb\\u000a eutectic alloy without increasing the soldering temperature. However, there are still some problems to be resolved, such as\\u000a the argument about the poor oxidation resistance and embrittlement behavior. In order to overcome these drawbacks, and further\\u000a enhance the properties of

Liang ZhangSong-bai; Song-bai Xue; Li-li Gao; Zhong Sheng; Huan Ye; Zheng-xiang Xiao; Guang Zeng; Yan Chen; Sheng-lin Yu

2010-01-01

435

Regulations and market trends in lead-free and halogen-free electronics  

Microsoft Academic Search

Purpose This paper seeks to investigate the electronics industry's reaction to environmental regulations specifically in terms of lead-free solders and halogen-free flame-retardants (FRs). Design\\/methodology\\/approach This work achieves its objective by discussing the various international environmental regulations pertaining to electronics manufacturing and relating the industry reactions to those regulations. It also provides the market trends related to lead- and

Lei Nie; Michael Pecht; Richard Ciocci

2007-01-01

436

Comparison of Printed Circuit Board Property Variations in Response to Simulated Lead-Free Soldering  

Microsoft Academic Search

Use of lead-free solders such as Sn\\/Ag\\/Cu results in exposure of printed circuit boards to higher temperatures during assembly compared with eutectic tin-lead solder. If the thermo-mechanical and electrical properties of the laminate materials get affected by exposure to this higher temperature, that may impact the performance and reliability of the circuit board. Variations, if any, in laminate material properties

Bhanu Sood; Ravikumar Sanapala; Diganta Das; Michael Pecht; C. Y. Huang; M. Y. Tsai

2010-01-01

437

Low temperature electromigration and thermomigration in lead-free solder joints  

Microsoft Academic Search

High current density and high temperature gradient are major reliability concern for next generation nanoelectronic packaging and power electronics. High current density experiments on lead free solder joints coated with NiAu and non-coated Cu pads were conducted at ?20, ?30, ?40 and ?50C ambient temperatures. The time to failure (TTF) shows that solder joints with NiAu coated Cu pads last

Cemal Basaran; Mohd F. Abdulhamid

2009-01-01

438

A novel mechanical shock test method to evaluate lead-free BGA solder joint reliability  

Microsoft Academic Search

Portable electronic products such as cell phones are often subjected to drop tests to simulate consumer usage and to ensure required field reliability is met. Product-level drop tests can cause solder joint failures in both lead-free and tin-lead BGA packages due to the combination of highly localized strain created by high strain-rate mechanical shock. In order to understand this phenomenon

Dave Reiff; Edwin Bradley

2005-01-01

439

Low temperature electromigration and thermomigration in lead-free solder joints  

Microsoft Academic Search

High current density and high temperature gradient are major reliability concern for next generation high density power electronics. High current density experiments on lead free solder joints coated with NiAu and non-coated Cu pads were conducted at -20C, -30C, -40C and -50C ambient temperatures. The time to failure (TTF) shows that solder joints with NiAu coated Cu pads last longer.

Mohd Foad Abdul Hamid; Cemal Basaran

2008-01-01

440

Effect of Nickel Pad Metallization Thickness on Fatigue Failure of BGA Lead-Free Solder Joints  

Microsoft Academic Search

The purpose of this paper is to present our work on the effect of nickel (Ni) pad metallization thickness on fatigue failure of lead-free solder joints after thermal aging. Cyclic three-point bending tests were carried out to investigate the relationship between intermetallic compound (IMC) layer development and the fatigue life of solder joints. After the fatigue tests, cross-sections of solder

Masaki Omiya; Takeshi Miyazaki; Kikuo Kishimoto; Masazumi Amagai

2008-01-01

441

Knowledge-based reliability qualification and an acceleration model for lead-free solder joint  

Microsoft Academic Search

Lead free solder joints in surface mount packages like ball grid array (BGA) have a great impact on the reliability of final products. In this study, the approach to knowledge-based qualification for solder joint reliability is fully described. An acceleration failure model has been derived for Sn3.0Ag0.5Cu based solder joint interconnect with dual inline memory module (DIMM) applications and to

Yuchul Hwang; Hwan-Ki Jeon; Young-Gyun Ryu; Juseong Kang

2011-01-01

442

Experimental investigation on the failure of lead-free solder joints under drop impact  

Microsoft Academic Search

Purpose The purpose of this paper is to investigate the mechanism of ball grid array (BGA) lead-free solder joint failure under board-level drop impact. Design\\/methodology\\/approach A round shaped test board was used. First, drop tests at three different heights were carried out. Then, dye stain testing and metallurgical analysis were performed in order to study the failure mechanism

Fang Liu; Guang Meng; Mei Zhao

2010-01-01

443

Reliability testing and data analysis of lead-free solder joints for high-density packages  

Microsoft Academic Search

Temperature cycling tests, and statistical analysis of the results, for various high-density packages on printed-circuit boards with Sn-Cu hot-air solder levelling, electroless nickel-immersion gold, and organic solder preservative finishes are investigated in this study. Emphasis is placed on the determination of the life distribution and reliability of the lead-free solder joints of these high-density package assemblies while they are subjected

John Lau; Nick Hoo; Rob Horsley; Joe Smetana; Dongkai Shangguan; Walter Dauksher; Dave Love; Irv Menis; Bob Sullivan

2004-01-01

444

Modeling and reliability analysis of lead-free solder joints of bottom leaded plastic (BLP) package  

Microsoft Academic Search

The electronic packaging and assembly technology is developing to high-density, fine-pitch and micromation. At the same time, an ever increasing need has developed for a lead-free solder joint interconnection due to the restrictions on the use of lead, and the upward spiraling market demand of green products. As a result the reliability of solder joint has attracted a great deal

Chen Xiangyang; Zhou Dejian

2006-01-01

445

Smog chamber reactivities of emissions from leaded and lead-free fuels  

Microsoft Academic Search

Work was undertaken to determine photochemical specific reactivities of emissions from automobiles using leaded-premium- and regular-grade fuels and prototype lead-free fuels of comparable octane quality. Emissions were photoirradiated in a 100-ft³ environmental (smog) chamber constructed of aluminum and Pyrex glass at three sets of initial hydrocarbon (HC) and oxides of nitrogen (NO\\/sub x\\/) concentrations. Reactivity was measured and expressed in

G. P. Jr. Sturm; B. Dimitriades

1973-01-01

446

Improving the performance of lead-free solder reinforced with multi-walled carbon nanotubes  

Microsoft Academic Search

In this study, varying weight fractions of multi-walled carbon nanotubes were successfully incorporated into 95.8Sn3.5Ag0.7Cu solder, to synthesize novel lead-free composite solders. The composite solders were synthesized via the powder metallurgy route of: blending, compaction, sintering and extrusion. The extruded materials were then characterized for their physical, thermal and mechanical properties. With the addition of increasing weight percentage of carbon

S. M. L. Nai; J. Wei; M. Gupta

2006-01-01

447

Design and analysis of a piezoelectric ultrasonic transducer for distance measurement  

Microsoft Academic Search

This paper describes a kind of bimorph flexural piezoelectric ultrasonic transducer (abbreviated as PUT) for distance measurement. A bimorph flexural PUT based on low-sintering piezoelectric ceramics PMN-PNN-PZT, which have high piezoelectric constant (d33>680pC\\/N), high electromechanical coupling factor (Kp=0.70?0.73), was introduced. The numerical and finite element analysis (abbreviated as FEA) of its resonant modes were investigated. An advanced laser scanning vibrometer

Zhilun Gui; Xiaobing Hu; Longtu Li

2002-01-01

448

Study of domain structure of poled (K,Na)NbO3 ceramics  

NASA Astrophysics Data System (ADS)

Domain structure may greatly affect the dielectric and piezoelectric properties of a ferroelectric ceramic material. However, no investigations on the domain structure of poled (K,Na)NbO3-based ceramics have been reported so far. Since (K0.50Na0.50)NbO3 is the basic composition for the important type of lead-free piezoelectric materials, domain structure of the poled (K0.50Na0.50)NbO3 ceramics with the average grain size of about 8 ?m were explored by observing the domain patterns with an acid etching technique in this study. It was found that domain patterns show usually either a single set of parallel domain stripes or a few sets of parallel domain stripes in polycrystalline grains. The average domain widths in different sets of parallel domain stripes vary largely from 150 nm to 750 nm. The intersection angels between two adjacent sets of domain stripes are around 45 or 135. Two models of domain configuration were proposed to explain those domain patterns that consist of more than two sets of parallel domain stripes. One is built up in the way that the intersection angles between two adjacent sets of domain stripes are acute and consists of 90-, 60- and 120-domain walls. The other one is formed in the way that the intersection angles between two adjacent sets of domain stripes are obtuse and is composed of 180-, 90- and 120-domain walls. Additionally, the change of intersection angle between two adjacent sets of domain stripes with varying the observation plane is discussed.

Qin, Yalin; Zhang, Jialiang; Gao, Yong; Tan, Yongqiang; Wang, Chunlei

2013-05-01

449

Piezoelectric drive circuit  

DOEpatents

A piezoelectric motor drive circuit is provided which utilizes the piezoelectric elements as oscillators and a Meacham half-bridge approach to develop feedback from the motor ground circuit to produce a signal to drive amplifiers to power the motor. The circuit automatically compensates for shifts in harmonic frequency of the piezoelectric elements due to pressure and temperature changes. 7 figs.

Treu, C.A. Jr.

1999-08-31

450

Optimal placement and active vibration control for piezoelectric smart flexible cantilever plate  

Microsoft Academic Search

Some flexible appendages of spacecraft are cantilever plate structures, such as sun plate and satellite antenna. Thus, vibration problem will be caused by parameter uncertainties and environmental disturbances. In this paper, piezoelectric ceramics patches are used as sensors and actuators to suppress the vibration of the smart flexible clamped plate. Firstly, modal equations and piezoelectric control equations of cantilever plate

Zhi-Cheng Qiu; Xian-Min Zhang; Hong-Xin Wu; Hong-Hua Zhang

2007-01-01

451

Piezoelectric films for 100MHz ultrasonic transducers  

Microsoft Academic Search

Piezoelectric aluminum nitride (AlN) and zinc oxide (ZnO) thin films were deposited by reactive magnetron sputtering for use in ultrasonic transducers in the 100- to 300-MHz regime. Pulse-echo ultrasonic transducers are being developed to image subsurface microstructure in metal and non-metal (ceramic) materials and components. A Krimholtz, Leedom, Matthaei (KLM) model was used to aid in the design of the

Peter M. Martin; Morris S. Good; John W. Johnston; Gerald J. Posakony; Leonard J. Bond; Susan L. Crawford

2000-01-01

452

Fabrication of piezoelectric fibers with metal core  

Microsoft Academic Search

A study on the fabrication of Pb(Nb,Ni)O3-Pb(Zr,Ti)O3 (PNN-PZT) piezoelectric ceramic fibers with a metal core is introduced. The green fibers were fabricated by extruding a mixture of PNN-PZT powder and organic solvent together with a 50 mm Pt core. The fibers of 250 mm in diameter and a few centimeters long are obtained without any cracks after sintered at 1200C.

Jinhao Qiu; Junji Tani; Naoki Yamada; Hirofumi Takahashi

2003-01-01

453

Engineered piezoelectricity in graphene.  

PubMed

We discover that piezoelectric effects can be engineered into nonpiezoelectric graphene through the selective surface adsorption of atoms. Our calculations show that doping a single sheet of graphene with atoms on one side results in the generation of piezoelectricity by breaking inversion symmetry. Despite their 2D nature, piezoelectric magnitudes are found to be comparable to those in 3D piezoelectric materials. Our results elucidate a designer piezoelectric phenomenon, unique to the nanoscale, that has potential to bring dynamical control to nanoscale electromechanical devices. PMID:22196055

Ong, Mitchell T; Reed, Evan J

2012-01-06

454

Effect of frit size on microwave properties of glassceramic in low temperature co-fired ceramics  

Microsoft Academic Search

For low temperature co-fired ceramics (LTCC) materials, glassceramic composites consisting of a BaNd2Ti5O14 ceramic and the lead-free rare earth derived boron glasses (L glass) were tested with different frit size. The glassceramic composites were evaluated for thermal properties and microwave dielectric properties (?r, Qf0: quality factor). At low temperature, the sintered body demonstrated applicable properties such as high relative density

Seongjin Hwang; Hyungsun Kim

2007-01-01

455

Morphotropic phase boundary and electrical properties in (1-x)Bi0.5Na0.5TiO3-xBi(Zn0.5Ti0.5)O3 lead-free piezoceramics  

NASA Astrophysics Data System (ADS)

(1-x)Bi0.5Na0.5TiO3-xBi(Zn0.5Ti0.5)O3 [(1-x)BNT-xBZT, x=0, 0.025, 0.0375, 0.050, and 0.075] lead-free piezoceramics were prepared and their structures and electrical properties were investigated. It is found that BZT can increase the Curie temperature of BNT. A morphotropic phase boundary (MPB) separating rhombohedral and tetragonal phases exists near x=0.0375. As the result, the MPB composition shows improved electrical properties; the saturated polarization, remnant polarization, and coercive field are 42.0 ?C/cm2, 36.5 ?C/cm2, and 3.5 kV/mm, respectively, while the piezoelectric coefficient, planar electromechanical coupling factor, and unipolar strain are 92 pC/N, 0.22, and 0.08%, respectively. The structures and electrical properties are discussed by comparing with that of other BNT-based piezoceramics. Our results do not only supplement for BNT-based lead-free piezoceramics, but also may provide a way to develop new lead-free piezoceramics with high Curie temperature.

Zhang, Shan-Tao; Yan, Feng; Yang, Bin

2010-06-01

456

Effect of Rapid Solidification on Structure and Properties of Some Lead-Free Solder Alloys  

Microsoft Academic Search

Four of the binary lead-free solder alloys of compositions Sn-0.5Cu, Sn-3.5Ag, Sn-5Sb and Sn-9Zn, were rapidly solidified by melt-spinning technique as a technique for producing new alloy compositions. The results show that rapid solidification causes formation of some intermetallic compounds such as Ag3Sn and Cu6Sn5 in the two alloys Sn-3.5Ag and Sn-0.5Cu, which cannot be formed at the equilibrium phase

Mustafa Kamal; El-Said Gouda

2006-01-01

457

Accelerated thermal fatigue of lead-free solder joints as a function of reflow cooling rate  

Microsoft Academic Search

Leadless chip resistor (LCR) assemblies were manufactured using both traditional tin-lead (Sn37Pb) and lead-free (Sn3.8Ag0.7Cu)\\u000a solders. The leadfree test vehicles were assembled using three different cooling rates: 1.6C\\/sec, 3.8C\\/sec, and 6.8C\\/sec.\\u000a They were then exposed to accelerated thermalcycling (ATC) tests between 0C and 100C with a 1014C\\/min ramp rate and a\\u000a 5-min dwell time. The test results indicated that these

Y. Qi; A. R. Zbrzezny; M. Agia; R. Lam; H. R. Ghorbani; P. Snugovsky; D. D. Perovic; J. K. Spelt

2004-01-01

458

Investigation on properties of Ga to Sn9Zn lead-free solder  

Microsoft Academic Search

The influences of different Ga content on the properties of Sn9Zn lead-free solder were investigated. The results indicate\\u000a that Ga plays an important role not only in the structure and melting behavior, but also in the solderability and mechanical\\u000a property. Sn9Zn0.5Ga shows finer and more uniform microstructure than Sn9Zn. With the addition of low-melting-point Ga,\\u000a TL (liquidus temperature) and TS

Wenxue Chen; Songbai Xue; Hui Wang; Jianxin Wang; Zongjie Han

2010-01-01

459

Creep Deformation of Lead-Free Sn3.5Ag-Bi Solders  

Microsoft Academic Search

Creep rupture properties of lead-free Sn-3.5Ag-based alloys with varying amounts of Bi were investigated using dog-bone-shaped rolled and heat-treated bulk specimens. Nominal compositions of Bi additions were 0, 2.5, 4.8, 7.5, and 10 wt%, respectively. The minimum strain rates (\\\\dot{\\\\varepsilon}min) were lowest for the 2.5Bi specimens. The stress exponents (n) of \\\\dot{\\\\varepsilon}min were usually around 4 0.6, with the exception

Seung Woo Shin; Jin Yu

2003-01-01

460

Creep rupture of lead-free Sn3.5Ag-Cu solders  

Microsoft Academic Search

Creep-rupture properties of lead-free Sn-3.5Ag-based alloys with varying amount of Cu were investigated using rolled and heat-treated\\u000a dog-bone-shaped specimens. Nominal compositions of added copper were 0 wt.%, 0.5 wt.%, 0.75 wt.%, 1.0 wt.%, and 1.5 wt.%.\\u000a During creep tests, the matrix hardness dropped significantly, and the minimum strain rates (\\u000a $$\\\\dot \\\\varepsilon _{min} $$\\u000a ) were lowest for the 0.75Cu

D. K. Joo; Jin Yu; S. W. Shin

2003-01-01

461

Mechanics concepts for failure in ferroelectric ceramics  

Microsoft Academic Search

The article reviews mechanics concepts suitable for analyzing defects (cracks, domain walls, etc.) in ferroelectric ceramics. Constitutive laws are summarized for dielectric, electrostrictive and piezoelectric ceramics. The formulation is based on an energy function of strain and induction, and a few experimental facts. Also summarized are the differential equations that govern stress and electric fields. Griffith's energy release rate is

Z. Suo

1991-01-01

462

Fabrication of curved ceramic\\/polymer composite transducer for ultrasonic imaging applications by fused deposition of ceramics  

Microsoft Academic Search

Fused Deposition of Ceramics (FDC), developed at Rutgers University, is a Solid Freeform Fabrication (SFF) technique where a three-dimensional green ceramic object is built, layer by layer, starting from a Computer Aided Design (CAD) file of the object. This technique was used to build novel piezoelectric ultrasonic transducers for medical imaging applications. Curved ceramic skeletons for 2-2 composite transducers were

G. M. Lous; I. A. Cornejo; T. F. McNulty; A. Safari; S. C. Danforth

1998-01-01

463

Lead-Free Low-Melting and Semiconductive Vanadate Glass Applicable to Low-Temperature Sealing  

NASA Astrophysics Data System (ADS)

We optimized the fundamental composition and additives in a semiconducting V2O5--P2O5--TeO2 glass system to develop lead-free low-melting glass suitable for low-temperature sealing below 400 C. Glass with a composition of 55.7V2O5--19.8P2O5--23.5TeO2 (mol %) has a low glass transformation temperature (Tg < 300 C) as well as hard crystallization, and it is desired as a low-temperature sealing material. The effects of adding BaO, Sb2O3, MnO2, or Fe2O3 to the fundamental composition of 55.7V2O5--19.8P2O5--23.5TeO2 (mol %) on the thermal properties and water-vapor resistance were then characterized. Adding 11.7 mol % Fe2O3 improved the water-vapor resistance drastically and decreased the thermal expansion coefficient without increasing Tg. Sealing at 360 C with our lead-free Fe2O3-added vanadate glass enabled practical airtight packaging on an electronic device.

Naito, Takashi; Aoyagi, Takuya; Sawai, Yuichi; Tachizono, Shinichi; Yoshimura, Kei; Hashiba, Yuji; Yoshimoto, Mamoru

2011-08-01

464

Evaluation of Bulk Mechanical Properties of Selected Lead-Free Solders in Tension and in Shear  

NASA Astrophysics Data System (ADS)

Lead-free solders are fast emerging as better alternatives to Sn-Pb solders. The reliability of a soldered joint to withstand imposed stresses in an assembly is decided by its mechanical properties. The present work is about the investigation of tensile and shear properties of four binary eutectic alloys Sn-3.5Ag, Sn-58Bi, Sn-0.7Cu, Sn-9Zn and a ternary alloy Sn-57Bi-1.3Zn in comparison with conventional Sn-38Pb alloy. It is observed that the lead-free solders have better mechanical properties than the latter. SEM studies of tensile and shear fracture show ductile dimples circular in tension and parabolic in shear modes supporting the mechanical behavior of the alloys investigated. Eutectic alloys Sn-Ag, Sn-Zn, and Sn-Cu form potential substitutes for Sn-Pb for electronic interconnects exposed to high temperatures, while Sn-Bi and Sn-Bi-Zn are attractive alternatives in addressing the need of lower processing temperatures in printed circuit boards and other applications.

Devaki Rani, S.; Murthy, G. S.

2013-03-01

465

Study on Dynamic Failure Model of Lead-Free Solders Using Shpb Techniques  

NASA Astrophysics Data System (ADS)

The dynamic compressive properties of 96.3Sn3Ag0.7Cu and 99.3Sn0.7Cu solders were studied by means of a split Hopkinson pressure bar at strain rates ranging from 500 to 2000 s-1. Tests were conducted at room temperature and under uniaxial compressive conditions. Eutectic SnPb solders were used as the reference. From the data of tests, it was found that yield strength and flow stress increased remarkably with the increase of strain rate. On logarithmic scales, the yield strength increased linearly with strain rate. These lead-free solders revealed certain visco-plastic behavior and strain rate sensitivity, which predicted using Johnson-Cook material model. Related parameters in the model were determined from the experiment. Compared with the typical Pb-containing solder Sn63Pb37, these lead-free solders showed some fine properties and could substitute some Pb-containing solder alloys in microelectronic components packaging and interconnects.

Niu, Xiaoyan; Yuan, Guozheng; Li, Zhigang; Shu, Xuefeng

466

Assessment of circuit board surface finishes for electronic assembly with lead-free solders  

SciTech Connect

The suitability of various metallic printed wiring board surface finishes was assessed for new technology applications that incorporate assembly with Lead-free solders. The manufacture of a lead-free product necessitates elimination of lead (Pb) from the solder, the circuit board as well as the component lead termination. It is critical however for the selected interconnect Pb-free solder and the corresponding printed wiring board (PWB) and component lead finishes to be mutually compatible. Baseline compatibility of select Pb-free solders with Pb containing PWB surface finish and components was assessed. This was followed by examining the compatibility of the commercially available CASTIN{trademark} (SnAgCuSb) Pb-free solder with a series of PWB metallic finishes: Ni/Au, Ni/Pd, and Pd/Cu. The compatibility was assessed with respect to assembly performance, solder joint integrity and long term attachment reliability. Solder joint integrity and mechanical behavior of representative 50 mil pitch 20I/O SOICs was determined before and after thermal stress. Mechanical pull test studies demonstrated that the strength of SnAgCuSb solder interconnections is notably greater than that of SnPb interconnections.

Ray, U.; Artaki, I.; Finley, D.W.; Wenger, G.M. [Bell Labs., Princeton, NJ (United States). Lucent Technologies; Pan, T.; Blair, H.D.; Nicholson, J.M. [Ford Motor Co., Dearborn, MI (United States); Vianco, P.T. [Sandia National Labs., Albuquerque, NM (United States)

1996-10-01

467

Evaluation of Diffusion Barrier Between Lead-Free Solder Systems and Thermoelectric Materials  

NASA Astrophysics Data System (ADS)

The intermetallic compound SnTe rapidly formed at interfaces between p-type bismuth telluride (Bi0.5Sb1.5Te3) thermoelectric materials and lead-free solders. The intermetallic compound influences the mechanical properties of the joints and the reliability of the thermoelectric modules. Various lead-free solder alloys, Sn-3.5Ag, Sn-3Ag-0.5Cu, Sn-0.7Cu, and Sn-2.5Ag-2Ni, were used to investigate the interfacial reactions. The results thus obtained show that Ag and Cu preferentially diffused into the Te-rich phase in Bi0.5Sb1.5Te3, so layers of Ag-Te and Cu-Te compounds could not form an effective diffusion barrier. Electroless nickel-phosphorus was plated at the interfaces to serve as a diffusion barrier, and the (Cu,Ni)6Sn5 compound formed instead of SnTe. Furthermore, the intermetallic compound NiTe formed between nickel- phosphorus and Bi0.5Sb1.5Te3 and also served as a diffusion barrier. A plot of thickness as a function of annealing time yielded the growth kinetics of the intermetallic compounds in the thermoelectric material systems. The activation energy for the growth of the NiTe intermetallic compound is 111 kJ/mol.

Lin, T. Y.; Liao, C. N.; Wu, Albert T.

2012-01-01

468

Evaluation of Bulk Mechanical Properties of Selected Lead-Free Solders in Tension and in Shear  

NASA Astrophysics Data System (ADS)

Lead-free solders are fast emerging as better alternatives to Sn-Pb solders. The reliability of a soldered joint to withstand imposed stresses in an assembly is decided by its mechanical properties. The present work is about the investigation of tensile and shear properties of four binary eutectic alloys Sn-3.5Ag, Sn-58Bi, Sn-0.7Cu, Sn-9Zn and a ternary alloy Sn-57Bi-1.3Zn in comparison with conventional Sn-38Pb alloy. It is observed that the lead-free solders have better mechanical properties than the latter. SEM studies of tensile and shear fracture show ductile dimples circular in tension and parabolic in shear modes supporting the mechanical behavior of the alloys investigated. Eutectic alloys Sn-Ag, Sn-Zn, and Sn-Cu form potential substitutes for Sn-Pb for electronic interconnects exposed to high temperatures, while Sn-Bi and Sn-Bi-Zn are attractive alternatives in addressing the need of lower processing temperatures in printed circuit boards and other applications.

Devaki Rani, S.; Murthy, G. S.

2013-08-01

469

Influence of ceramic reinforcements on the wettability and mechanical properties of novel lead-free solder composites  

Microsoft Academic Search

In the present study, two sets of Sn3.5 Ag0.7 Cu solder-based composite materials were successfully synthesized using the powder metallurgy route of blending, compaction, sintering and extrusion. Varying amount of titanium diboride particulates and multi-walled carbon nanotubes were introduced respectively as reinforcements to obtain the two sets of composite solders. Following synthesis, the extruded materials were characterized in terms of

S. M. L. Nai; J. Wei; M. Gupta

2006-01-01

470

The Effects of High Temperature Storage on Lead Free Solder Joint Material Strength Using Pull Test Method  

Microsoft Academic Search

The purpose of this study is to discuss on the effect of high temperature storage (HTS) on lead free solder joint material for ball grid array application using pull test method. Three samples of different lead free solder joint material were choosed in this experiment that are Sn3.8Ag0.7Cu (SAC387), Sn2.3Ag0.08Ni 0.01Co (SANC), and Sn3.5Ag. Then the lead free solder joint

MuhammadNajib Harif; I. Ahmad; A. Zaharim

2006-01-01

471

A high-temperature double-mode piezoelectric ultrasonic linear motor  

NASA Astrophysics Data System (ADS)

A miniature piezoelectric ultrasonic linear motor (piezoelectric vibrator sizes: 4.7 13.5 2 mm3) has been studied for precise actuation at 200 C high-temperature. This piezoelectric linear motor was made of (1-x)BiScO3-xPbTiO3 piezoelectric ceramic with a high curie temperature (428 C) and it was operated in first longitudinal and the second bending double-mode. Our experimental results showed that the linear motor moves smoothly at the temperature as high as 200 C with a driving force of 0.35 N and a speed up to 42 mm/s.

Li, Xiaotian; Chen, Jianguo; Chen, Zhijiang; Dong, Shuxiang

2012-08-01

472

Actuation Behavior of Multilayer Ceramic Actuator Induced by ElectroMechanical Loading  

Microsoft Academic Search

The actuation behavior of multilayer ceramic actuators (MCA) using PMN-PZT ceramics was investigated under the combined high electromechanical loading. When electric field and compressive stress are simultaneously applied to the ceramics, the piezoceramics is expected to be different from that of ceramics induced by only one quantity, electric field or mechanical load. This property difference was estimated via piezoelectric equation.

Mun-Su Ha; Soon-Jong Jeong; Jung-Hyuk Koh; Jae-Sung Song; Yeon-Hak Jeong

2006-01-01

473

Switchable static friction of piezoelectric composite--silicon wafer contacts  

NASA Astrophysics Data System (ADS)

The meso-scale surface roughness of piezoelectric fiber composites can be manipulated by applying an electric field to a piezocomposite with a polished surface. In the absence of an applied voltage, the tips of the embedded piezoelectric ceramic fibers are below the surface of the piezocomposite and a silicon wafer counter surface rests solely on the matrix region of the piezocomposite surface. When actuated, the piezoelectric ceramic fibers protrude from the surface and the wafer rests solely on these protrusions. A threefold decrease in engineering static friction coefficient upon actuation of the piezocomposite was observed: from ?* = 1.65 to ?* = 0.50. These experimental results could be linked to the change in contact surface area and roughness using capillary adhesion theory, which relates the adhesive force to the number and size of the contacting asperities for the different surface states.

van den Ende, D. A.; Fischer, H. R.; Groen, W. A.; van der Zwaag, S.

2013-04-01

474

Consideration of impedance matching techniques for efficient piezoelectric energy harvesting.  

PubMed

This study investigates multiple levels of impedance-matching methods for piezoelectric energy harvesting in order to enhance the conversion of mechanical to electrical energy. First, the transduction rate was improved by using a high piezoelectric voltage constant (g) ceramic material having a magnitude of g33 = 40 x 10(-3) V m/N. Second, a transducer structure, cymbal, was optimized and fabricated to match the mechanical impedance of vibration source to that of the piezoelectric transducer. The cymbal transducer was found to exhibit approximately 40 times higher effective strain coefficient than the piezoelectric ceramics. Third, the electrical impedance matching for the energy harvesting circuit was considered to allow the transfer of generated power to a storage media. It was found that, by using the 10-layer ceramics instead of the single layer, the output current can be increased by 10 times, and the output load can be redu