... Accession Number : AD0756050. Title : An Accelerated Method of Fatigue Testing and Parameters of Fatigue Curves,. Corporate ...
DTIC Science & Technology
Safer alternative to spacecraft explosive bolts may accelerate fatigue .... A Bolt To Be Fatigue-Tested or simply broken by accelerated fatigue would be ...
NASA Website
The fatigue behavior of multidirectional graphite-epoxy laminates was analyzed theoretically and experimentally in an effort to establish an accelerated testing methodology. Analysis of the failure mechanism in fatigue of the laminates led to the determin...
National Technical Information Service (NTIS)
... Accession Number : AD0740390. Title : Accelerated Fatigue Tests of Wire Rope. Descriptive Note : Final rept. (Volume I) 10 Feb 67-9 Mar 68,. ...
... retardation and acceleration) in fatigue crack growth. ... Similar comparisons on high strength 4340 steel ... fatigue life of test specimens without flaws, it ...
The types and quantities of wear particles generated during accelerated ball rolling contact fatigue
NASA Technical Reports Server (NTRS)
To assist the development and interpretation of the Concorde Major Fatigue Test a technique for accelerating fatigue testing was evaluated on structural box specimens under combined mechanical and thermal loadings. It is shown that for a moderate level of...
... FATIGUE LIFE OF LEADS AND SOLDER ... DURING HIGH-LEVEL TESTING IS POSSIBLE ... THE EXPONENT FOR COPPER LEAD-WIRE FAILURES ...
Apr 21, 2009 ... Spur Gear Fatigue Test Rigs. ... Provides accelerated fatigue life testing for standard spur gears; Standard gears are 88.9 mm (3.5") pitch ...
A corrosion fatigue test procedure based on fracture mechanics is a severe test of materials compatibility. Thus, fatigue-type tests can be used to demonstrate an accelerated cracking behavior. However, care must be taken when comparing fatigue crack ...
Energy Citations Database
In the full-scale fatigue testing of the Concorde there is a need to accumulate damage at a higher rate than in service in order to meet certification requirements. One contribution to the more rapid testing of the Concorde comes from accelerating the rat...
The objective of this program is to develop and validate an accelerated fatigue test for elastomers and to evaluate candidate cardiovascular elastomers with this test. In this reporting period, a 100-position fatigue tester was debugged. Preliminary fatig...
As a result of observed cracks in the fabricated center sills of many freight cars in the FAST consist, a special Fatigue Analysis Test (FAT) was conducted on the FAST Track during August and September of 1978. This report provides an analysis of the stat...
could lead to fatigue failure of the bond material. ... this paper, separate testing was performed and concluded ... Aluminum could be found, the analysis used the ...
Apr 15, 1998 ... Constant stress-rate ("dynamic fatigue") testing has been used for several decades to characterize the slow crack growth behavior of glass ...
Fatigue testing for twelve SG tubular fabrics with various textile parameters was performed under pulsatile pressure by an Accelerated fatigue tester. Two time points as of 0, and 1 x 10(8) cycles were selected. The percentage change of tubular diameter, fabric count, porosity, and water permeability before and ...
PubMed
Possibilities for reducing fatigue-test time for supersonic-transport materials and structures were studied in tests with simulated flight-by-flight loading. In order to determine whether short-time tests were feasible, the results of accelerated tests (2...
The optical switching properties of a photochromic spirooxazine compound in retrofit polyester film and in poly(vinyl butyral) have been measured. The light fatigue resistance of these two optical switching elements were tested by an accelerated method. T...
Laser Doppler Anemometry (LDA) and accelerated fatigue testing were used in an attempt to assess the
... The results demonstrated the capability of the accelerated life test rig to provide high cycle rate and adequate flexure to fatigue the film samples. ...
Fully reversed, load-controlled uniaxial push-pull fatigue tests at room temperature have been performed in air and in mercury on specimens of type 316LN stainless steel. The results indicate a significant influence of mercury on fatigue properties. Compared to specimens tested in air, specimens ...
... Accession Number : ADD441995. Title : Fatigue Acceleration of Brittle Fracture in PE Pipes,. Corporate Author : Personal ...
Components in rotational machinery such as turbine blades used in military aircraft engines are subjected to low-amplitude, high-frequency loads in the kHz range. Under high cycle fatigue (HCF), the initiation state of a crack consumes most of the life of the component. Vibratory stresses may therefore result in unexpected failures of the material. Hence, there is a need for ...
NASA Astrophysics Data System (ADS)
The fatigue-related behavior of a linear elastic system (LES) can be efficiently identified using acceleration response if the frequency response function between the acceleration input and the stress response (FRFas) can be predetermined. In this paper, the spectral damage of an LES is predicted using energy isoclines, whose function ...
Surface state plays a major role in the crack nucleation process of pure metals in the High-Cycle-Fatigue (HCF) as well as in the Ultra-High-Cycle-Fatigue (UHCF) regime. Therefore, in studies dealing with HCF or UHCF, special attention is paid to the evolution of surface degradation during fatigue life. The ...
Cracking by thermal fatigue is its probable long-term failure mechanism, but it is not clear how to perform accelerated thermal-cycle tests to get a ...
Some of the wheel and rail wear results from the current test at the Facility for Accelerated Service Testing are analyzed in the light of both adhesive and fatigue wear theories. This analysis suggests that the wheel/rail wear processes occurring in the ...
According to the related standards, an in vitro corrosion fatigue testing of coronary stents was designed. The stents were fixed in the latex tubes, which were full of 0.9% saline solution, and radial stress was produced for simulating natural vessel. The accelerated fatigue test was performed ...
Eliminating post-irradiation melting and stabilizing the residual free radicals of radiation crosslinked ultra-high molecular weight polyethylene (UHMWPE) with Vitamin-E resulted in improved fatigue crack propagation resistance without compromising wear resistance. We designed a cantilever post bending test to determine the bending ...
PubMed Central
A previously developed test design for accelerated aging of photovoltaic modules was experimentally evaluated. The studies included a review of relevant field experience, environmental chamber cycling of full-size modules, and electrical and physical evaluation of the effects of accelerated aging during and after the ...
The acceleration of hydrogen diffusion in the fatigue process of AISI type 304 and 316L meta-stable austenitic stainless steels was studied by paying attention to the relation between fatigue slip bands and hydrogen emission. Slip bands were formed in tension-compression fatigue tests of round ...
A review is presented of the general problems of fatigue failure which lead to the necessity for the fatigue testing of materials, components, and structures. The objectives of a fatigue testing program are discussed and the philosophies associated with v...
... Title : Flexural Fatigue Testing of Polyesters,. ... Abstract : A method is decribed for evaluating flexural fatigue properties of unsaturated polyesters. ...
May 13, 2008 ... The Advanced Metallics Branch hosts several fatigue testing machines that are a portion of a larger Division capability in fatigue testing ...
... Accession Number : ADD126012. Title : Determination of Fatigue Life by Testing Materials for Thermal Fatigue,. Corporate Author : ...
Laser Doppler Anemometry (LDA) and accelerated fatigue testing were used in an attempt to assess the durability of two cardiac value bioprostheses. The LDA system was used to monitor the function of the cardiac valves over time. This was done through flow...
A special flexible joint of Ti casing was developed for the joint between the riser base and the tree or wellhead where most of the riser bending and flexing is concentrated. Accelerated fatigue tests equivalent to many years in service showed unchanged joint integrity. (DLC)
or corrosion products, can jeopardize the objective of the mission. ...... Overheat Cracking c. Bulk Fatigue d. Fretting of Fit Surface ..... that greater amounts of acid were formed with 440C than with 52100 steel and that the ...
Feb 16, 2010 ... Fatigue Testing Rig. ... Image Detail: Fatigue Testing Rig. Fatigue Testing Rig � View larger version. Fatigue Testing Rig. GD Star Rating ...
A sudden drop in power after a beam interruption leads to thermal fatigue effects in structural components in the blanket of an accelerator driven system. These thermal fatigue effects limit component lifetimes. A sudden return to power after a beam interruption can contribute significant additional thermal fatigue ...
DOE Information Bridge
... Title : STRAIN AND FATIGUE TESTING OF LARGE EXPANSION BELLOWS,. ... NO FAILURE OF EITHER BELLOWS WAS OBSERVED. ...
... Abstract : THE APPLICATION OF NONDESTRUCTIVE TESTING (NDT) TO THE ENGINEERING ASPECTS OF THE FATIGUE PHENOMENON ...
... Accession Number : AD0650176. Title : FATIGUE TESTS OF GROUSERS FOR AMPHIBIAN TRACTORS,. Corporate Author ...
... but also determining their operational fatigue life and thereby ... nucleation and time of its accelerated propagation ... of cycles, sequence of high and low ...
... Accession Number : ADD127277. Title : Fatigue and Creep-Fatigue Testing of Steam Filled Tubular Alloy 800 Specimens,. ...
... Accession Number : ADD139827. Title : Fatigue and Creep-Fatigue Testing of Bellows at Elevated Temperature,. Descriptive Note : Journal Article,. ...
The prediction of long-term fatigue life of innovative CFRP laminates for marine use under temperature and water environments were performed by our developed accelerated testing methodology based on the time- temperature superposition principle. Furthermo...
A study was conducted to evaluate the roles of crack closure and microstructure in the fatigue growth of short cracks. Testing was performed at R ratios of 0.1, 0.5, and 0.7. At all R ratios short cracks exhibited accelerated growth rates in comparison to...
The optical switching properties of a photochromic spirooxazine compound in retrofit polyester film and in poly(vinyl butyral) have been measured. The light fatigue resistance of these two optical switching elements were tested by an accelerated method. The length of photochromic activity of the optical switching elements can be ...
... HOLES(OPENINGS), INTERFERENCE, FATIGUE(MECHANICS), LABORATORIES, EXPANSION, WINGS, FASTENINGS, FATIGUE TESTS ...
... made to perform systematic test on AA7075 Aluminum and SAE ... Descriptors : *STEEL, *ALUMINUM ALLOYS, *FATIGUE(MECHANICS), FATIGUE ...
The test configuration was a flexural fatigue arrangement, ... or strength. The detrimental effect of fretting on the fatigue life of mechanical com- ...
Fatigue tests were conducted to determine the actual reduction in fatigue life due to weight removal
... Abstract : Rotating bending fatigue tests were carried out on ... the ductile iron was austenitized at 900 or ... the fatigue strength was correlated with the ...
... Accession Number : ADD110474. Title : CORROSION FATIGUE - OR - HOW TO REPLACE THE FULL-SCALE FATIGUE TEST,. ...
Because of the nature of running, the forces encountered require a proper coordination of joint action of the lower extremity to dissipate the ground reaction forces and accelerations through the kinetic chain. Running-related muscle fatigue may reduce the shock absorbing capacity of the lower extremity and alter running kinematics. The purpose of this ...
