Corrosion-Activated Micro-Containers for Environmentally Friendly Corrosion Protective Coatings

NASA Technical Reports Server (NTRS)

Li, Wenyan; Buhrow, J. W.; Zhang, X.; Johnsey, M. N.; Pearman, B. P.; Jolley, S. T.; Calle, L. M.

2016-01-01

This work concerns the development of environmentally friendly encapsulation technology, specifically designed to incorporate corrosion indicators, inhibitors, and self-healing agents into a coating, in such a way that the delivery of the indicators and inhibitors is triggered by the corrosion process, and the delivery of self-healing agents is triggered by mechanical damage to the coating. Encapsulation of the active corrosion control ingredients allows the incorporation of desired autonomous corrosion control functions such as: early corrosion detection, hidden corrosion detection, corrosion inhibition, and self-healing of mechanical damage into a coating. The technology offers the versatility needed to include one or several corrosion control functions into the same coating.The development of the encapsulation technology has progressed from the initial proof-of-concept work, in which a corrosion indicator was encapsulated into an oil-core (hydrophobic) microcapsule and shown to be delivered autonomously, under simulated corrosion conditions, to a sophisticated portfolio of micro carriers (organic, inorganic, and hybrid) that can be used to deliver a wide range of active corrosion ingredients at a rate that can be adjusted to offer immediate as well as long-term corrosion control. The micro carriers have been incorporated into different coating formulas to test and optimize the autonomous corrosion detection, inhibition, and self-healing functions of the coatings. This paper provides an overview of progress made to date and highlights recent technical developments, such as improved corrosion detection sensitivity, inhibitor test results in various types of coatings, and highly effective self-healing coatings based on green chemistry. The NASA Kennedy Space Centers Corrosion Technology Lab at the Kennedy Space Center in Florida, U.S.A. has been developing multifunctional smart coatings based on the microencapsulation of environmentally friendly corrosion indicators, inhibitors and self-healing agents. This allows the incorporation of autonomous corrosion control functionalities, such as corrosion detection and inhibition as well as the self-healing of mechanical damage, into coatings. This paper presents technical details on the characterization of inhibitor-containing particles and their corrosion inhibitive effects using electrochemical and mass loss methods.Three organic environmentally friendly corrosion inhibitors were encapsulated in organic microparticles that are compatible with desired coatings. The release of the inhibitors from the microparticles in basic solution was studied. Fast release, for immediate corrosion protection, as well as long-term release for continued protection, was observed.The inhibition efficacy of the inhibitors, incorporated directly and in microparticles, on carbon steel was evaluated. Polarization curves and mass loss measurements showed that, in the case of 2MBT, its corrosion inhibition effectiveness was greater when it was delivered from microparticles.

Poly (3,4-ethylenedioxythiophene) graphene oxide composite coatings for controlling magnesium implant corrosion.

PubMed

Catt, Kasey; Li, Huaxiu; Cui, X Tracy

2017-01-15

Magnesium (Mg) is a promising biodegradable implant material because of its appropriate mechanical properties and safe degradation products. However, in vivo corrosion speed and hydrogen gas production need to be controlled for uses in biomedical applications. Here we report the development of a conducting polymer 3,4-ethylenedioxythiphene (PEDOT) and graphene oxide (GO) composite coating as a corrosion control layer. PEDOT/GO was electropolymerized on Mg samples in ethanol media. The coated Mg samples were subjected to various corrosion tests. The PEDOT/GO coating significantly reduced the rate of corrosion as evidenced by lower Mg ion concentration and pH of the corrosion media. In addition, the coating decreased the evolved hydrogen. Electrochemical analysis of the corroding samples showed more positive corrosion potential, a decreased corrosion current, and an increase in the polarization resistance. PEDOT/GO corrosion protection is attributed to three factors; an initial passive layer preventing solution ingress, buildup of negative charges in the film, and formation of corrosion protective Mg phosphate layer through redox coupling with Mg corrosion. To explore the biocompatibility of the coated implants in vitro, corrosion media from PEDOT/GO coated or uncoated Mg samples were exposed to cultured neurons where PEDOT/GO coated samples showed decreased toxicity. These results suggest that PEDOT/GO coating will be an effective treatment for controlling corrosion of Mg based medical implants. Coating Mg substrates with a PEDOT/GO composite coating showed a significant decrease in corrosion rate. While conducting polymer coatings have been used to prevent corrosion on various metals, there has been little work on the use of these coatings for Mg. Additionally, to our knowledge, there has not been a report of the combined used of conducting polymer and GO as a corrosion control layer. Corrosion control is attributed to an initial barrier layer followed by electrochemical coupling of the PEDOT/GO coating with the substrate to facilitate the formation of a protective phosphate layer. This coupling also resulted in a decrease in hydrogen produced during corrosion, which could further improve the host tissue integration of Mg implants. This work elaborates on the potential for electroactive polymers to serve as corrosion control methods. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Controlled-Release Microcapsules for Smart Coatings for Corrosion Applications

NASA Technical Reports Server (NTRS)

2008-01-01

Corrosion is a serious problem that has enormous costs and serious safety implications. Localized corrosion, such as pitting, is very dangerous and can cause catastrophic failures. The NASA Corrosion Technology Laboratory at Kennedy Space Center is developing a smart coating based on pH-sensitive microcapsules for corrosion applications. These versatile microcapsules are designed to be incorporated into a smart coating and deliver their core content when corrosion starts. Corrosion indication was the first function incorporated into the microcapsules. Current efforts are focused on incorporating the corrosion inhibition function through the encapsulation of corrosion inhibitors into water core and oil core microcapsules. Scanning electron microscopy (SEM) images of encapsulated corrosion inhibitors are shown.

Molten salt corrosion of SiC and Si3N4

NASA Technical Reports Server (NTRS)

Jacobson, Nathan S.; Smialek, James L.; Fox, Dennis S.

1988-01-01

Industrial systems such as heat engines and heat exchangers involve harsh environments. The structural materials are subjected to high temperatures as well as corrosive gases and condensed phases. Past experience with metal alloys has shown that these condensed phases can be particularly corrosive and are often the limiting factor in the operation of these systems. In a heat engine the most common condensed corrodent is Na2SO4 whereas in a heat exchanger an oxide slag may be present. The primary emphasis is on Na2SO4 induced corrosion, however, similarities and differences to oxide slag are also discussed. The extensive research on corrosion of metal alloys has led to understanding and controlling corrosion for these materials. Currently silicon based ceramics are prime candidates for the applications discussed. Therefore it is important to understand the effects of condensed phase deposits on this emerging class of high temperature materials. Both the thermodynamic and strength of the ceramic is also examined. Finally some control strategies for corrosion of silicon based ceramics are explored.

Evaluation of bridge cables corrosion using acoustic emission technique

NASA Astrophysics Data System (ADS)

Li, Dongsheng; Ou, Jinping

2010-04-01

Owing to the nature of the stress, corrosion of bridge cable may result in catastrophic failure of the structure. However, using electrochemical techniques isn't fully efficient for the detection and control on line of the corrosion phenomenon. A non-destructive testing method based on acoustic emission technique monitoring bridge cable corrosion was explored. The steel strands were placed at room temperature in 5% NaCl solution. Acoustic emission (AE) characteristic parameters were recorded in the whole corrosion experiment process. Based on the plot of cumulated acoustic activity, the bridge cables corrosion included three stages. It can be clearly seen that different stages have different acoustic emission signal characteristics. The AE characteristic parameters would be increased with cables corrosion development. Finally, the bridge cables corrosion experiment with different stress state and different corrosion environment was performed. The results shows that stress magnitude only affects the bridge cable failure time, however, the AE characteristic parameters value has changed a little. It was verified that AE technique can be used to detect the bridge cable early corrosion, investigating corrosion developing trend, and in monitoring and evaluating corrosion damages.

Surface treatments for controlling corrosion rate of biodegradable Mg and Mg-based alloy implants

PubMed Central

Uddin, M S; Hall, Colin; Murphy, Peter

2015-01-01

Due to their excellent biodegradability characteristics, Mg and Mg-based alloys have become an emerging material in biomedical implants, notably for repair of bone as well as coronary arterial stents. However, the main problem with Mg-based alloys is their rapid corrosion in aggressive environments such as human bodily fluids. Previously, many approaches such as control of alloying materials, composition and surface treatments, have been attempted to regulate the corrosion rate. This article presents a comprehensive review of recent research focusing on surface treatment techniques utilised to control the corrosion rate and surface integrity of Mg-based alloys in both in vitro and in vivo environments. Surface treatments generally involve the controlled deposition of thin film coatings using various coating processes, and mechanical surfacing such as machining, deep rolling or low plasticity burnishing. The aim is to either make a protective thin layer of a material or to change the micro-structure and mechanical properties at the surface and sub-surface levels, which will prevent rapid corrosion and thus delay the degradation of the alloys. We have organised the review of past works on coatings by categorising the coatings into two classes—conversion and deposition coatings—while works on mechanical treatments are reviewed based on the tool-based processes which affect the sub-surface microstructure and mechanical properties of the material. Various types of coatings and their processing techniques under two classes of coating and mechanical treatment approaches have been analysed and discussed to investigate their impact on the corrosion performance, biomechanical integrity, biocompatibility and cell viability. Potential challenges and future directions in designing and developing the improved biodegradable Mg/Mg-based alloy implants were addressed and discussed. The literature reveals that no solutions are yet complete and hence new and innovative approaches are required to leverage the benefit of Mg-based alloys. Hybrid treatments combining innovative biomimetic coating and mechanical processing would be regarded as a potentially promising way to tackle the corrosion problem. Synergetic cutting-burnishing integrated with cryogenic cooling may be another encouraging approach in this regard. More studies focusing on rigorous testing, evaluation and characterisation are needed to assess the efficacy of the methods. PMID:27877829

A New Corrosion Sensor to Determine the Start and Development of Embedded Rebar Corrosion Process at Coastal Concrete

PubMed Central

Xu, Chen; Li, Zhiyuan; Jin, Weiliang

2013-01-01

The corrosion of reinforcements induced by chloride has resulted to be one of the most frequent causes of their premature damage. Most corrosion sensors were designed to monitor corrosion state in concrete, such as Anode-Ladder-System and Corrowatch System, which are widely used to monitor chloride ingress in marine concrete. However, the monitoring principle of these corrosion sensors is based on the macro-cell test method, so erroneous information may be obtained, especially from concrete under drying or saturated conditions due to concrete resistance taking control in macro-cell corrosion. In this paper, a fast weak polarization method to test corrosion state of reinforcements based on electrochemical polarization dynamics was proposed. Furthermore, a new corrosion sensor for monitoring the corrosion state of concrete cover was developed based on the proposed test method. The sensor was tested in cement mortar, with dry-wet cycle tests to accelerate the chloride ingress rate. The results show that the corrosion sensor can effectively monitor chloride penetration into concrete with little influence of the relative humidity in the concrete. With a reasonable corrosion sensor electrode arrangement, it seems the Ohm-drop effect measured by EIS can be ignored, which makes the tested electrochemical parameters more accurate. PMID:24084117

A new corrosion sensor to determine the start and development of embedded rebar corrosion process at coastal concrete.

PubMed

Xu, Chen; Li, Zhiyuan; Jin, Weiliang

2013-09-30

The corrosion of reinforcements induced by chloride has resulted to be one of the most frequent causes of their premature damage. Most corrosion sensors were designed to monitor corrosion state in concrete, such as Anode-Ladder-System and Corrowatch System, which are widely used to monitor chloride ingress in marine concrete. However, the monitoring principle of these corrosion sensors is based on the macro-cell test method, so erroneous information may be obtained, especially from concrete under drying or saturated conditions due to concrete resistance taking control in macro-cell corrosion. In this paper, a fast weak polarization method to test corrosion state of reinforcements based on electrochemical polarization dynamics was proposed. Furthermore, a new corrosion sensor for monitoring the corrosion state of concrete cover was developed based on the proposed test method. The sensor was tested in cement mortar, with dry-wet cycle tests to accelerate the chloride ingress rate. The results show that the corrosion sensor can effectively monitor chloride penetration into concrete with little influence of the relative humidity in the concrete. With a reasonable corrosion sensor electrode arrangement, it seems the Ohm-drop effect measured by EIS can be ignored, which makes the tested electrochemical parameters more accurate.

Smart Coating for Corrosion Indication and Prevention: Recent Progress

NASA Technical Reports Server (NTRS)

Li, Wenyan; Hintze, Paul; Calle, Luz M.; Buhrow, Jerry; Curran, Jerry; Muehlberg, A. J.; Gelling, V. J.; Webster, D. C.; Croll, S. G.; Contu, F.;

Microencapsulation of Corrosion Indicators for Smart Coatings

NASA Technical Reports Server (NTRS)

Li, Wenyan; Buhrow, Jerry W.; Jolley, Scott T.; Calle, Luz M.; Hanna,Joshua S.; Rawlins, James W.

2011-01-01

A multifunctional smart coating for the autonomous detection, indication, and control of corrosion is been developed based on microencapsulation technology. This paper summarizes the development, optimization, and testing of microcapsules specifically designed for early detection and indication of corrosion when incorporated into a smart coating. Results from experiments designed to test the ability of the microcapsules to detect and indicate corrosion, when blended into several paint systems, show that these experimental coatings generate a color change, indicative of spot specific corrosion events, that can be observed with the naked eye within hours rather than the hundreds of hours or months typical of the standard accelerated corrosion test protocols.. Key words: smart coating, corrosion detection, microencapsulation, microcapsule, pH-sensitive microcapsule, corrosion indicator, corrosion sensing paint

Civil Engineering Corrosion Control. Volume 1. Corrosion Control - General

DTIC Science & Technology

1975-01-01

is generated in the boiler by the decomposition of carbonates and bicar- bonates of sodium, calcium, and magnesium. (c) The pH Range. Natural waters...and products of decomposition Acting as either anodic or cathodic depolarizers. 4.4.1 Forms of Microorganisms. In almost any soil or water, there are... 1945 . Based on field tests of the Iron and Steel Institute Corrosion Committee reported by J.C. Hudson (J. Iron Steel Inst., 11, 209, 1943), with

Investigating inhibition of microbes inducing microbiologically-influenced-corrosion by Tectona grandis based Fe-nanoparticle material

NASA Astrophysics Data System (ADS)

Okeniyi, Joshua Olusegun; Omotosho, Olugbenga Adeshola; Inyang, Michael Anietie; Okeniyi, Elizabeth Toyin; Nwaokorie, Ikechi Thaddeus; Adidi, Emmanuel Amanogho; Owoeye, Taiwo Felicia; Nwakudu, Kelechukwu Chinedu; Akinlabu, Deborah Kehinde; Gabriel, Olanrewaju Oyewale; Taiwo, Olugbenga Samson; Awotoye, Olufisayo Adebola

2017-02-01

In this paper, inhibition of microbes inducing microbiologically-influenced-corrosion (MIC) of metals by Tectona grandis based Fe (iron) Nanoparticle material was investigated. For this, extract was obtained from the leaf of Tectona grandis and this was employed as precursor for synthesizing the Fe-nanoparticle material. From this, the synthesized plant extract based nanoparticle material was characterized using scanning electron microscopy and energy dispersive spectroscopy (SEM+EDS) instrument. The developed Fe bio-nanoparticle material was then employed for sensitivity and/or resistance study application against different strains of microbes that are known to induce microbiologically-influenced-corrosion, in metallic materials, and for this, microbial growth inhibition effect was compared with that from a commercial antibiotic employed as control. Results showed that the Tectona grandis based Fe-nanoparticle exhibited good inhibition effects on the growth of many of the MIC inducing microbes investigated. Sensitivity measures of zone of inhibition against the growth of MIC inducing microbial strains either outperformed or compares well with that obtained from the commercial antibiotic control, in the study. These results indicate positive prospect on the suitability of Fe bio-nanoparticle for corrosion inhibition applications for the protection of metals against microbiological corrosion influencing environment.

Defense Infrastructure: DOD Should Improve Reporting and Communication on Its Corrosion Prevention and Control Activities

DTIC Science & Technology

2013-05-01

Cycle Prediction for Equipment and Facilities 33.1 33.1 12 FAR16 Corrosion Prevention of Rebar in Concrete in Critical Facilities Located in Coastal...through 2007. 16 N-F-229 Integrated Concrete Pier Piling Repair and Corrosion Protection System 1.9 1.9 2006 17 FNV01 Corrosion Protection...Protection System 3.4 3.0 2007 21 F07NV03 Corrosion Inhibitor Evaluation for Concrete Repairs 16.8 16.8 22 F07NV04 Satellite Based Remote Monitoring

Long Duration Life Test of Propylene Glycol Water Based Thermal Fluid Within Thermal Control Loop

NASA Technical Reports Server (NTRS)

Le, Hung; Hill, Charles; Stephan, Ryan A.

2010-01-01

Evaluations of thermal properties and resistance to microbial growth concluded that 50% Propylene Glycol (PG)-based fluid and 50% de-ionized water mixture was desirable for use as a fluid within a vehicle s thermal control loop. However, previous testing with a commercial mixture of PG and water containing phosphate corrosion inhibitors resulted in corrosion of aluminum within the test system and instability of the test fluid. This paper describes a follow-on long duration testing and analysis of 50% Propylene Glycol (PG)-based fluid and 50% de-ionized water mixture with inorganic corrosion inhibitors used in place of phosphates. The test evaluates the long-term fluid stability and resistance to microbial and chemical changes

Pitting corrosion as a mixed system: coupled deterministic-probabilistic simulation of pit growth

NASA Astrophysics Data System (ADS)

Ibrahim, Israr B. M.; Fonna, S.; Pidaparti, R.

2018-05-01

Stochastic behavior of pitting corrosion poses a unique challenge in its computational analysis. However, it also stems from electrochemical activity causing general corrosion. In this paper, a framework for corrosion pit growth simulation based on the coupling of the Cellular Automaton (CA) and Boundary Element Methods (BEM) is presented. The framework assumes that pitting corrosion is controlled by electrochemical activity inside the pit cavity. The BEM provides the prediction of electrochemical activity given the geometrical data and polarization curves, while the CA is used to simulate the evolution of pit shapes based on electrochemical activity provided by BEM. To demonstrate the methodology, a sample case of local corrosion cells formed in pitting corrosion with varied dimensions and polarization functions is considered. Results show certain shapes tend to grow in certain types of environments. Some pit shapes appear to pose a higher risk by being potentially significant stress raisers or potentially increasing the rate of corrosion under the surface. Furthermore, these pits are comparable to commonly observed pit shapes in general corrosion environments.

Demonstration and Validation of Stainless Steel Materials for Critical Above Grade Piping in Highly Corrosive Locations

DTIC Science & Technology

2017-05-01

Protecting And Bonding Reinforcing Steel In Cement -Based Composites, Corrosion 2009, Atlanta, GA, 22-26 March 2009. 7. Hock, V., O. Marshall, S...ER D C/ CE RL T R- 17 -1 3 DoD Corrosion Prevention and Control Program Demonstration and Validation of Stainless Steel Materials for...ERDC/CERL TR-17-13 May 2017 Demonstration and Validation of Stainless Steel Materials for Critical Above-Grade Piping in Highly Corrosive

49 CFR 195.589 - What corrosion control information do I have to maintain?

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false What corrosion control information do I have to... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.589 What corrosion control... sufficient detail to demonstrate the adequacy of corrosion control measures or that corrosion requiring...

49 CFR 195.589 - What corrosion control information do I have to maintain?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false What corrosion control information do I have to... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.589 What corrosion control... sufficient detail to demonstrate the adequacy of corrosion control measures or that corrosion requiring...

49 CFR 195.589 - What corrosion control information do I have to maintain?

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false What corrosion control information do I have to... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.589 What corrosion control... sufficient detail to demonstrate the adequacy of corrosion control measures or that corrosion requiring...

49 CFR 195.589 - What corrosion control information do I have to maintain?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false What corrosion control information do I have to... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.589 What corrosion control... sufficient detail to demonstrate the adequacy of corrosion control measures or that corrosion requiring...

49 CFR 195.589 - What corrosion control information do I have to maintain?

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false What corrosion control information do I have to... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.589 What corrosion control... sufficient detail to demonstrate the adequacy of corrosion control measures or that corrosion requiring...

A dual-task design of corrosion-controlling and osteo-compatible hexamethylenediaminetetrakis- (methylene phosphonic acid) (HDTMPA) coating on magnesium for biodegradable bone implants application.

PubMed

Zhao, Sheng; Chen, Yingqi; Liu, Bo; Chen, Meiyun; Mao, Jinlong; He, Hairuo; Zhao, Yuancong; Huang, Nan; Wan, Guojiang

2015-05-01

Magnesium as well as its alloys appears increasingly as a revolutionary bio-metal for biodegradable implants application but the biggest challenges exist in its too fast bio-corrosion/degradation. Both corrosion-controllable and bio-compatible Mg-based bio-metal is highly desirable in clinic. In present work, hexamethylenediaminetetrakis (methylenephosphonic acid) [HDTMPA, (H2 O3 P-CH2 )2 -N-(CH2 )6 -N-(CH2 -PO3 H2 )2 ], as a natural and bioactive organic substance, was covalently immobilized and chelating-deposited onto Mg surface by means of chemical conversion process and dip-coating method, to fullfill dual-task performance of corrosion-protective and osteo-compatible functionalities. The chemical grafting of HDTMPA molecules, by participation of functional groups on pretreated Mg surface, ensured a firmly anchored base layer, and then sub-sequential chelating reactions of HDTMPA molecules guaranteed a homogenous and dense HDTMPA coating deposition on Mg substrate. Electrochemical corrosion and immersion degradation results reveal that the HDTMPA coated Mg provides a significantly better controlled bio-corrosion/degradation behavior in phosphate buffer saline solution as compared with untreated Mg from perspective of clinic requirement. Moreover, the HDTMPA coated Mg exhibits osteo-compatible in that it induces not only bioactivity of bone-like apatite precipitation but also promotes osteoblast cells adhesion and proliferation. Our well-controlled biodegradable and biocompatible HDTMPA modified Mg might bode well for next generation bone implant application. © 2014 Wiley Periodicals, Inc.

49 CFR 192.491 - Corrosion control records.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Corrosion control records. 192.491 Section 192.491... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.491 Corrosion... detail to demonstrate the adequacy of corrosion control measures or that a corrosive condition does not...

49 CFR 192.491 - Corrosion control records.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Corrosion control records. 192.491 Section 192.491... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.491 Corrosion... detail to demonstrate the adequacy of corrosion control measures or that a corrosive condition does not...

49 CFR 192.491 - Corrosion control records.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Corrosion control records. 192.491 Section 192.491... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.491 Corrosion... detail to demonstrate the adequacy of corrosion control measures or that a corrosive condition does not...

49 CFR 192.491 - Corrosion control records.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Corrosion control records. 192.491 Section 192.491... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.491 Corrosion... detail to demonstrate the adequacy of corrosion control measures or that a corrosive condition does not...

49 CFR 192.491 - Corrosion control records.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Corrosion control records. 192.491 Section 192.491... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.491 Corrosion... detail to demonstrate the adequacy of corrosion control measures or that a corrosive condition does not...

Magnesium based degradable biomaterials: A review

NASA Astrophysics Data System (ADS)

Gu, Xue-Nan; Li, Shuang-Shuang; Li, Xiao-Ming; Fan, Yu-Bo

2014-09-01

Magnesium has been suggested as a revolutionary biodegradable metal for biomedical applications. The corrosion of magnesium, however, is too rapid to match the rates of tissue healing and, additionally, exhibits the localized corrosion mechanism. Thus it is necessary to control the corrosion behaviors of magnesium for their practical use. This paper comprehensively reviews the research progress on the development of representative magnesium based alloys, including Mg-Ca, Mg-Sr, Mg-Zn and Mg-REE alloy systems as well as the bulk metallic glass. The influence of alloying element on their microstructures, mechanical properties and corrosion behaviors is summarized. The mechanical and corrosion properties of wrought magnesium alloys are also discussed in comparison with those of cast alloys. Furthermore, this review also covers research carried out in the field of the degradable coatings on magnesium alloys for biomedical applications. Calcium phosphate and biodegradable polymer coatings are discussed based on different preparation techniques used. We also compare the effect of different coatings on the corrosion behaviors of magnesium alloys substrate.

Controlled ferrite content improves weldability of corrosion-resistant steel

NASA Technical Reports Server (NTRS)

Malin, C. O.

1967-01-01

Corrosion-resistant steel that adds restrictions on chemical composition to ensure sufficient ferrite content decreases the tendency of CRES to develop cracks during welding. The equations restricting composition are based on the Schaeffler constitution diagram.

High-Performance Corrosion-Resistant Materials: Iron-Based Amorphous-Metal Thermal-Spray Coatings: SAM HPCRM Program ? FY04 Annual Report ? Rev. 0 - DARPA DSO & DOE OCRWM Co-Sponsored Advanced Materials Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farmer, J; Haslam, J; Wong, F

2007-09-19

The multi-institutional High Performance Corrosion Resistant Materials (HPCRM) Team is cosponsored by the Defense Advanced Projects Agency (DARPA) Defense Science Office (DSO) and the Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM), and has developed new corrosion-resistant, iron-based amorphous metals that can be applied as coatings with advanced thermal spray technology. Two compositions have corrosion resistance superior to wrought nickel-based Alloy C-22 (UNS No. N06022) in very aggressive environments, including concentrated calcium-chloride brines at elevated temperature. Corrosion costs the Department of Defense billions of dollars every year, with an immense quantity of material in various structures undergoingmore » corrosion. For example, in addition to fluid and seawater piping, ballast tanks, and propulsions systems, approximately 345 million square feet of structure aboard naval ships and crafts require costly corrosion control measures. The use of advanced corrosion-resistant materials to prevent the continuous degradation of this massive surface area would be extremely beneficial. The Fe-based corrosion-resistant, amorphous-metal coatings under development may prove of importance for applications on ships. Such coatings could be used as an 'integral drip shield' on spent fuel containers, as well as protective coatings that could be applied over welds, thereby preventing exposure to environments that might cause stress corrosion cracking. In the future, such new high-performance iron-based materials could be substituted for more-expensive nickel-based alloys, thereby enabling a reduction in the $58-billion life cycle cost for the long-term storage of the Nation's spent nuclear fuel by tens of percent.« less

49 CFR 192.461 - External corrosion control: Protective coating.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Protective coating... for Corrosion Control § 192.461 External corrosion control: Protective coating. (a) Each external protective coating, whether conductive or insulating, applied for the purpose of external corrosion control...

49 CFR 192.461 - External corrosion control: Protective coating.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Protective coating... for Corrosion Control § 192.461 External corrosion control: Protective coating. (a) Each external protective coating, whether conductive or insulating, applied for the purpose of external corrosion control...

Corrosion Control in the US Navy: Ships & USMC Vehicles

DTIC Science & Technology

2014-11-18

Mr. Matthew Koch Corrosion Control & Prevention Executive Presented by E. Dail Thomas II, Consultant 18 November 2014 Corrosion Control in... control number. 1. REPORT DATE 18 NOV 2014 2. REPORT TYPE 3. DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE Corrosion Control in...and Technology DoD Corrosion Prevention and Control IPT Director, Corrosion Policy and Oversight USD Acquisition, Technology and Logistics ASD

49 CFR 192.467 - External corrosion control: Electrical isolation.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Electrical isolation... for Corrosion Control § 192.467 External corrosion control: Electrical isolation. (a) Each buried or... pipeline is necessary to facilitate the application of corrosion control. (c) Except for unprotected copper...

49 CFR 192.467 - External corrosion control: Electrical isolation.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Electrical isolation... for Corrosion Control § 192.467 External corrosion control: Electrical isolation. (a) Each buried or... pipeline is necessary to facilitate the application of corrosion control. (c) Except for unprotected copper...

49 CFR 195.559 - What coating material may I use for external corrosion control?

Code of Federal Regulations, 2011 CFR

2011-10-01

... corrosion control? 195.559 Section 195.559 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.559 What coating material may I use for external corrosion control? Coating material for external corrosion control under...

49 CFR 195.559 - What coating material may I use for external corrosion control?

Code of Federal Regulations, 2010 CFR

2010-10-01

... corrosion control? 195.559 Section 195.559 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.559 What coating material may I use for external corrosion control? Coating material for external corrosion control under...

49 CFR 195.559 - What coating material may I use for external corrosion control?

Code of Federal Regulations, 2014 CFR

2014-10-01

... corrosion control? 195.559 Section 195.559 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.559 What coating material may I use for external corrosion control? Coating material for external corrosion control under...

49 CFR 195.559 - What coating material may I use for external corrosion control?

Code of Federal Regulations, 2012 CFR

2012-10-01

... corrosion control? 195.559 Section 195.559 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.559 What coating material may I use for external corrosion control? Coating material for external corrosion control under...

49 CFR 195.559 - What coating material may I use for external corrosion control?

Code of Federal Regulations, 2013 CFR

2013-10-01

... corrosion control? 195.559 Section 195.559 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.559 What coating material may I use for external corrosion control? Coating material for external corrosion control under...

Internal Corrosion and Deposition Control

EPA Science Inventory

This chapter reviews the current knowledge of the science of corrosion control and control of scaling in drinking water systems. Topics covered include: types of corrosion; physical, microbial and chemical factors influencing corrosion; corrosion of specific materials; direct ...

Controlling the corrosion and cathodic activation of magnesium via microalloying additions of Ge

PubMed Central

Liu, R. L.; Hurley, M. F.; Kvryan, A.; Williams, G.; Scully, J. R.; Birbilis, N.

2016-01-01

The evolution of corrosion morphology and kinetics for magnesium (Mg) have been demonstrated to be influenced by cathodic activation, which implies that the rate of the cathodic partial reaction is enhanced as a result of anodic dissolution. This phenomenon was recently demonstrated to be moderated by the use of arsenic (As) alloying as a poison for the cathodic reaction, leading to significantly improved corrosion resistance. The pursuit of alternatives to toxic As is important as a means to imparting a technologically safe and effective corrosion control method for Mg (and its alloys). In this work, Mg was microalloyed with germanium (Ge), with the aim of improving corrosion resistance by retarding cathodic activation. Based on a combined analysis herein, we report that Ge is potent in supressing the cathodic hydrogen evolution reaction (reduction of water) upon Mg, improving corrosion resistance. With the addition of Ge, cathodic activation of Mg subject to cyclic polarisation was also hindered, with beneficial implications for future Mg electrodes. PMID:27350286

Corrosion study of a highly durable electrolyzer based on cold crucible technique for pyrochemical reprocessing of spent nuclear oxide fuel

NASA Astrophysics Data System (ADS)

Takeuchi, M.; Arai, Y.; Kase, T.; Nakajima, Y.

2013-01-01

The application of the cold crucible technique to a pyrochemical electrolyzer used in the oxide-electrowinning method, which is a method for the pyrochemical reprocessing of spent nuclear oxide fuel, is proposed as a means for improving corrosion resistance. The electrolyzer suffers from a severe corrosion environment consisting of molten salt and corrosive gas. In this study, corrosion tests for several metals in molten 2CsCl-NaCl at 923 K with purging chlorine gas were conducted under controlled material temperature conditions. The results revealed that the corrosion rates of several materials were significantly decreased by the material cooling effect. In particular, Hastelloy C-22 showed excellent corrosion resistance with a corrosion rate of just under 0.01 mm/y in both molten salt and vapor phases by controlling the material surface at 473 K. Finally, an engineering-scale crucible composed of Hastelloy C-22 was manufactured to demonstrate the basic function of the cold crucible. The cold crucible induction melting system with the new concept Hastelloy crucible showed good compatibility with respect to its heating and cooling performances.

49 CFR 192.475 - Internal corrosion control: General.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Internal corrosion control: General. 192.475... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.475 Internal corrosion control: General. (a) Corrosive gas may not be transported by...

49 CFR 192.475 - Internal corrosion control: General.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Internal corrosion control: General. 192.475... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.475 Internal corrosion control: General. (a) Corrosive gas may not be transported by...

49 CFR 192.477 - Internal corrosion control: Monitoring.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Internal corrosion control: Monitoring. 192.477... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.477 Internal corrosion control: Monitoring. If corrosive gas is being transported, coupons...

49 CFR 192.477 - Internal corrosion control: Monitoring.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Internal corrosion control: Monitoring. 192.477... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.477 Internal corrosion control: Monitoring. If corrosive gas is being transported, coupons...

Corrosion probe. Innovative technology summary report

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Over 253 million liters of high-level waste (HLW) generated from plutonium production is stored in mild steel tanks at the Department of Energy (DOE) Hanford Site. Corrosion monitoring of double-shell storage tanks (DSTs) is currently performed at Hanford using a combination of process knowledge and tank waste sampling and analysis. Available technologies for corrosion monitoring have progressed to a point where it is feasible to monitor and control corrosion by on-line monitoring of the corrosion process and direct addition of corrosion inhibitors. The electrochemical noise (EN) technique deploys EN-based corrosion monitoring probes into storage tanks. This system is specifically designedmore » to measure corrosion rates and detect changes in waste chemistry that trigger the onset of pitting and cracking. These on-line probes can determine whether additional corrosion inhibitor is required and, if so, provide information on an effective end point to the corrosion inhibitor addition procedure. This report describes the technology, its performance, its application, costs, regulatory and policy issues, and lessons learned.« less

Events as power source: wireless sustainable corrosion monitoring.

PubMed

Sun, Guodong; Qiao, Guofu; Zhao, Lin; Chen, Zhibo

2013-12-17

This study presents and implements a corrosion-monitoring wireless sensor platform, EPS (Events as Power Source), which monitors the corrosion events in reinforced concrete (RC) structures, while being powered by the micro-energy released from the corrosion process. In EPS, the proposed corrosion-sensing device serves both as the signal source for identifying corrosion and as the power source for driving the sensor mote, because the corrosion process (event) releases electric energy; this is a novel idea proposed by this study. For accumulating the micro-corrosion energy, we integrate EPS with a COTS (Commercial Off-The-Shelf) energy-harvesting chip that recharges a supercapacitor. In particular, this study designs automatic energy management and adaptive transmitted power control polices to efficiently use the constrained accumulated energy. Finally, a set of preliminary experiments based on concrete pore solution are conducted to evaluate the feasibility and the efficacy of EPS.

49 CFR 192.455 - External corrosion control: Buried or submerged pipelines installed after July 31, 1971.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective coating...

49 CFR 192.457 - External corrosion control: Buried or submerged pipelines installed before August 1, 1971.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...

49 CFR 192.457 - External corrosion control: Buried or submerged pipelines installed before August 1, 1971.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...

49 CFR 192.459 - External corrosion control: Examination of buried pipeline when exposed.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Examination of buried... Requirements for Corrosion Control § 192.459 External corrosion control: Examination of buried pipeline when... portion must be examined for evidence of external corrosion if the pipe is bare, or if the coating is...

49 CFR 192.459 - External corrosion control: Examination of buried pipeline when exposed.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Examination of buried... Requirements for Corrosion Control § 192.459 External corrosion control: Examination of buried pipeline when... portion must be examined for evidence of external corrosion if the pipe is bare, or if the coating is...

49 CFR 192.457 - External corrosion control: Buried or submerged pipelines installed before August 1, 1971.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...

49 CFR 192.455 - External corrosion control: Buried or submerged pipelines installed after July 31, 1971.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective coating...

49 CFR 192.455 - External corrosion control: Buried or submerged pipelines installed after July 31, 1971.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective coating...

49 CFR 192.459 - External corrosion control: Examination of buried pipeline when exposed.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Examination of buried... Requirements for Corrosion Control § 192.459 External corrosion control: Examination of buried pipeline when... portion must be examined for evidence of external corrosion if the pipe is bare, or if the coating is...

49 CFR 192.455 - External corrosion control: Buried or submerged pipelines installed after July 31, 1971.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective coating...

49 CFR 192.459 - External corrosion control: Examination of buried pipeline when exposed.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Examination of buried... Requirements for Corrosion Control § 192.459 External corrosion control: Examination of buried pipeline when... portion must be examined for evidence of external corrosion if the pipe is bare, or if the coating is...

49 CFR 192.457 - External corrosion control: Buried or submerged pipelines installed before August 1, 1971.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...

49 CFR 192.457 - External corrosion control: Buried or submerged pipelines installed before August 1, 1971.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...

49 CFR 192.459 - External corrosion control: Examination of buried pipeline when exposed.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Examination of buried... Requirements for Corrosion Control § 192.459 External corrosion control: Examination of buried pipeline when... portion must be examined for evidence of external corrosion if the pipe is bare, or if the coating is...

pH Responsive Microcapsules for Corrosion Control

NASA Technical Reports Server (NTRS)

Calle, Luz Marina; Li, Wenyan; Muehlberg, Aaron; Boraas, Samuel; Webster, Dean; JohnstonGelling, Victoria; Croll, Stuart; Taylor, S Ray; Contu, Francesco

2008-01-01

The best coatings for corrosion protection provide not only barriers to the environment, but also a controlled release of a corrosion inhibitor, as demanded by the presence of corrosion or mechanical damage. NASA has developed pH sensitive microcapsules (patent pending) that can release their core contents when corrosion starts. The objectives of the research presented here were to encapsulate non-toxic corrosion inhibitors, to incorporate the encapsulated inhibitors into paint formulations, and to test the ability of the paints to control corrosion. Results showed that the encapsulated corrosion inhibitors, specifically Ce(NO3)3 , are effective to control corrosion over long periods of time when incorporated at relatively high pigment volume concentrations into a paint formulation.

Characterization of Encapsulated Corrosion Inhibitors for Environmentally Friendly Smart Coatings

NASA Technical Reports Server (NTRS)

Pearman, Benjamin Pieter; Li, Wenyan; Buhrow, Jerry; Zhang, Xuejun; Surma, Jan; Fitzpatrick, Lilly; Montgomery, Eliza; Calle, Luz Marina

2014-01-01

Research efforts are under way to replace current corrosion inhibitors with more environmentally friendly alternatives. However, problems with corrosion inhibition efficiency, coating compatibility and solubility have hindered the use of many of these materials as simple pigment additives.This paper will present technical details on how the Corrosion Technology Lab at NASAs Kennedy Space Center (KSC) has addressed these issues by encapsulating environmentally friendly inhibitors into organic and inorganic microparticles and microcapsules. The synthetic process for polymer particles was characterized and post-synthesis analysis was performed to determine the interactions between the inhibitors and the encapsulation material. The pH-controlled release of inhibitors from various particle formulations in aqueous base was monitored and compared to both electrochemical and salt immersion accelerated corrosion experiment. Furthermore, synergistic corrosion inhibition effects observed during the corrosion testing of several inhibitor combinations will be presented.

49 CFR 193.2631 - Internal corrosion control.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Internal corrosion control. 193.2631 Section 193... GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2631 Internal corrosion control. Each component that is subject to internal corrosive attack must be protected from internal corrosion by— (a...

Electrochemical Behavior of Al-B4C Metal Matrix Composites in NaCl Solution

PubMed Central

Han, Yu-Mei; Chen, X.-Grant

2015-01-01

Aluminum based metal matrix composites (MMCs) have received considerable attention in the automotive, aerospace and nuclear industries. One of the main challenges using Al-based MMCs is the influence of the reinforcement particles on the corrosion resistance. In the present study, the corrosion behavior of Al-B4C MMCs in a 3.5 wt.% NaCl solution were investigated using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) techniques. Results indicated that the corrosion resistance of the composites decreased when increasing the B4C volume fraction. Al-B4C composite was susceptible to pitting corrosion and two types of pits were observed on the composite surface. The corrosion mechanism of the composite in the NaCl solution was primarily controlled by oxygen diffusion in the solution. In addition, the galvanic couples that formed between Al matrix and B4C particles could also be responsible for the lower corrosion resistance of the composites. PMID:28793574

The relative stress-corrosion-cracking susceptibility of candidate aluminum-lithium alloys for aerospace applications

NASA Technical Reports Server (NTRS)

Pizzo, P. P.

1982-01-01

Stress corrosion tests of Al-Li-Cu powder metallurgy alloys are described. Alloys investigated were Al-2.6% Li-1.4% and Al-2.6% Li-1.4% Cu-1.6% Mg. The base properties of the alloys were characterized. Process, heat treatment, and size/orientational effects on the tensile and fracture behavior were investigated. Metallurgical and electrochemical conditions are identified which provide reproducible and controlled parameters for stress corrosion evaluation. Preliminary stress corrosion test results are reported. Both Al-Li-Cu alloys appear more susceptible to stress corrosion crack initiation than 7075-T6 aluminum, with the magnesium bearing alloy being the most susceptible. Tests to determine the threshold stress intensity for the base and magnesium bearing alloys are underway. Twelve each, bolt loaded DCB type specimens are under test (120 days) and limited crack growth in these precracked specimens has been observed. General corrosion in the aqueous sodium chloride environment is thought to be obscuring results through crack tip blunting.

Installation Restoration Program Records Search for Davis-Monthan Air Force Base, Arizona.

DTIC Science & Technology

1982-08-01

inspection labs, and corrosion -2- control shops. These industrial operations generate varying quantities of waste oils , fuels , *solvents, and cleaners. The...standard procedures for the disposition of the majority of the waste oils , fuels , solvents, and cleaners has been (1) fire department training...and corrosion control shops. These industrial operations generate varying quantities of waste oils , fuels , solvents, and cleaners. The total quantity

Corrosion Control Specialist Career Ladder AFSC 53530, 53550, 53570, and 53690

DTIC Science & Technology

1975-03-01

AD-AO08 189 CORROSION CONTROL SPECIALIST CAREER LADDER AFSC 53530, 53550, 53570, AND 53690 Air Force Occupational Measurement Center Lackland Air... Force Base, Texas 1 March 1975 I DISTRIBUTED BY: National Technical Information Service U. S. DEPARTMENT OF COMMERCE *I 11 5091 OCCUPATIONAL SURVEY...DISCUSSION OF BACKGROUJND INFORMATION --------------------------- xxvi 01L< R PREFACE This report presents the results cf detailed Air Force

Corrosion Prevention and Control Planning Guidebook Spiral 3

DTIC Science & Technology

2007-09-01

programs. 5. Develop and recommend corrective and preventive procedures based on reliability and maintainability analyses of field data on similar in...One of the many challenges facing the Program/Acquisition Managers is the ability to develop a meaningful Corrosion Prevention and Control Plan...designated program manager of all activities associated with the acquisition, development , production, fielding , sustainment, and disposal of a DoD weapon

Durability of recycled aggregate concrete using pozzolanic materials.

PubMed

Ann, K Y; Moon, H Y; Kim, Y B; Ryou, J

2008-01-01

In this study, pulverized fuel ash (PFA) and ground granulated blast furnace slag (GGBS) were used to compensate for the loss of strength and durability of concrete containing recycled aggregate. As a result, 30% PFA and 65% GGBS concretes increased the compressive strength to the level of control specimens cast with natural granite gravel, but the tensile strength was still lowered at 28 days. Replacement with PFA and GGBS was effective in raising the resistance to chloride ion penetrability into the concrete body, measured by a rapid chloride ion penetration test based on ASTM C 1202-91. It was found that the corrosion rate of 30% PFA and 65% GGBS concretes was kept at a lower level after corrosion initiation, compared to the control specimens, presumably due to the restriction of oxygen and water access. However, it was less effective in increasing the chloride threshold level for steel corrosion. Hence, it is expected that the corrosion time for 30% PFA and 65% GGBS concrete containing recycled aggregate mostly equates to the corrosion-free life of control specimens.

A Meta-Analysis Of Corrosion Studies for Maritime Patrol and Reconnaissance Aircraft (MPRA)

DTIC Science & Technology

2016-09-01

performed onsite. Aircraft rating was based upon the presence and/or extent of paint adhesion, paint cracking , clean ability, fluid damage, oxidation...because of corrosion control maintenance. No significant issues were observed related to paint cracking , fluid damage, corrosion, and clean ability of...HEXAMETHYLENEDIISOCYANATE 822-06-0 83194 X-310A; POLYURETHANE CATALYST XYLENE 1330-20-7 82649 X-530; HS EPOXY ENAMEL CURING SOLUTION BUTANOL 71-36-3

DOE-DARPA High-Performance Corrosion-Resistant Materials (HPCRM), Annual HPCRM Team Meeting & Technical Review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farmer, J; Brown, B; Bayles, B

The overall goal is to develop high-performance corrosion-resistant iron-based amorphous-metal coatings for prolonged trouble-free use in very aggressive environments: seawater & hot geothermal brines. The specific technical objectives are: (1) Synthesize Fe-based amorphous-metal coating with corrosion resistance comparable/superior to Ni-based Alloy C-22; (2) Establish processing parameter windows for applying and controlling coating attributes (porosity, density, bonding); (3) Assess possible cost savings through substitution of Fe-based material for more expensive Ni-based Alloy C-22; (4) Demonstrate practical fabrication processes; (5) Produce quality materials and data with complete traceability for nuclear applications; and (6) Develop, validate and calibrate computational models to enable lifemore » prediction and process design.« less

A new, bright and hard aluminum surface produced by anodization

NASA Astrophysics Data System (ADS)

Hou, Fengyan; Hu, Bo; Tay, See Leng; Wang, Yuxin; Xiong, Chao; Gao, Wei

2017-07-01

Anodized aluminum (Al) and Al alloys have a wide range of applications. However, certain anodized finishings have relatively low hardness, dull appearance and/or poor corrosion resistance, which limited their applications. In this research, Al was first electropolished in a phosphoric acid-based solution, then anodized in a sulfuric acid-based solution under controlled processing parameters. The anodized specimen was then sealed by two-step sealing method. A systematic study including microstructure, surface morphology, hardness and corrosion resistance of these anodized films has been conducted. Results show that the hardness of this new anodized film was increased by a factor of 10 compared with the pure Al metal. Salt spray corrosion testing also demonstrated the greatly improved corrosion resistance. Unlike the traditional hard anodized Al which presents a dull-colored surface, this newly developed anodized Al alloy possesses a very bright and shiny surface with good hardness and corrosion resistance.

[The effect of bacteria reaction time on corrosion properties of Ni-Cr alloys pretreated with different proteins].

PubMed

Qi, Han-quan; Zhang, Song-mei; Qian, Chao; Yuan-Li, Zheng

2015-12-01

To evaluate the corrosion properties of absorbed protein on the surface of NiCr alloys, and provide experimental base for corrosion resistance of dental casting alloys. NiCr alloy specimens were divided into 3 groups: one group was exposed to the artificial saliva(control group), and the other 2 groups were exposed to the artificial saliva with 1% bovine serum albumin(BSA), or 0.22% lysozyme(LSZ). Group of BSA and group of LSZ were the experimental group. Specimens in 3 groups were cultured in solution of Streptococcus mutans for 12 h, 24 h, 36 h and 48h, and investigated with electrochemical impedance spectroscopy measurement(EIS) and potentiodynamic polarization measurement(POT) to determine the corrosion resistance of the alloys. The data was analyzed with SPSS 17.0 software package. The results indicated that the corrosion resistance of both BSA group and LSZ group were higher than that of the control group (P<0.05) and LSZ group was superior to BSA group cultured in the solution of Streptococcus mutans for 12 h. When cultured for 24 h, the corrosion resistance of BSA group and LSZ group had no significant difference (P>0.05), but was still higher than that of the control group. After 36 h culture time, the control group and the BSA group had no statistical difference in corrosion resistance （P>0.05), while the LSZ group had the poorest corrosion resistance. When the culture time extended to 48 h, the control group had a better corrosion resistance compared with the BAS group and the LSZ group(P<0.05), but BSA group had displayed lower corrosion properties than LSZ group. The potentiodynamic polarization curve and electrochemical impedance spectroscopy had similar results. The adhesion of BSA and LSZ on the surface of the NiCr alloys in the early time could effectively inhibit the corrosive effect of Streptococcus mutans. The LSZ had better effect than BSA. With the continuing role of bacteria and the consumption of the absorb protein, the corrosion resistance of NiCr alloys toward Streptococcus mutans becomes lower than the alloys without absorb protein, which demonstrated that the adhesion of protein would change the surface structure of NiCr alloys and BSA had a greater effect.

49 CFR 193.2629 - External corrosion control: buried or submerged components.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

49 CFR 193.2629 - External corrosion control: buried or submerged components.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

49 CFR 193.2629 - External corrosion control: buried or submerged components.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

49 CFR 193.2629 - External corrosion control: buried or submerged components.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

Electrochemical Behavior of Sn-9Zn-xTi Lead-Free Solders in Neutral 0.5M NaCl Solution

NASA Astrophysics Data System (ADS)

Wang, Zhenghong; Chen, Chuantong; Jiu, Jinting; Nagao, Shijo; Nogi, Masaya; Koga, Hirotaka; Zhang, Hao; Zhang, Gong; Suganuma, Katsuaki

2018-03-01

Electrochemical techniques were employed to study the electrochemical corrosion behavior of Sn-9Zn-xTi (x = 0, 0.05, 0.1, 0.2 wt.%) lead-free solders in neutral 0.5M NaCl solution, aiming to figure out the effect of Ti content on the corrosion properties of Sn-9Zn, providing information for the composition design of Sn-Zn-based lead-free solders from the perspective of corrosion. EIS results reveal that Ti addition was involved in the corrosion product layer and changed electrochemical interface behavior from charge transfer control process to diffusion control process. The trace amount of Ti addition (0.05 wt.%) can refine the microstructure and improve the corrosion resistance of Sn-9Zn solder, evidenced by much lower corrosion current density (i corr) and much higher total resistance (R t). Excess Ti addition (over 0.1 wt.%) led to the formation of Ti-containing IMCs, which were confirmed as Sn3Ti2 and Sn5Ti6, deteriorating the corrosion resistance of Sn-9Zn-xTi solders. The main corrosion products were confirmed as Sn3O(OH)2Cl2 mixed with small amount of chlorine/oxide Sn compounds.

Electrochemical Behavior of Sn-9Zn- xTi Lead-Free Solders in Neutral 0.5M NaCl Solution

NASA Astrophysics Data System (ADS)

Wang, Zhenghong; Chen, Chuantong; Jiu, Jinting; Nagao, Shijo; Nogi, Masaya; Koga, Hirotaka; Zhang, Hao; Zhang, Gong; Suganuma, Katsuaki

2018-05-01

Electrochemical techniques were employed to study the electrochemical corrosion behavior of Sn-9Zn- xTi ( x = 0, 0.05, 0.1, 0.2 wt.%) lead-free solders in neutral 0.5M NaCl solution, aiming to figure out the effect of Ti content on the corrosion properties of Sn-9Zn, providing information for the composition design of Sn-Zn-based lead-free solders from the perspective of corrosion. EIS results reveal that Ti addition was involved in the corrosion product layer and changed electrochemical interface behavior from charge transfer control process to diffusion control process. The trace amount of Ti addition (0.05 wt.%) can refine the microstructure and improve the corrosion resistance of Sn-9Zn solder, evidenced by much lower corrosion current density ( i corr) and much higher total resistance ( R t). Excess Ti addition (over 0.1 wt.%) led to the formation of Ti-containing IMCs, which were confirmed as Sn3Ti2 and Sn5Ti6, deteriorating the corrosion resistance of Sn-9Zn- xTi solders. The main corrosion products were confirmed as Sn3O(OH)2Cl2 mixed with small amount of chlorine/oxide Sn compounds.

Characterization and prediction of carbon steel corrosion in diluted seawater containing pentaborate

NASA Astrophysics Data System (ADS)

Fukaya, Yuichi; Watanabe, Yutaka

2018-01-01

This study addresses the influence of Na2B10O16, which may be used for criticality control of fuel debris in the Fukushima Daiichi Nuclear Power Station, on the corrosion behavior of carbon steel in diluted artificial seawater. The corrosion forms of carbon steel were categorized as uniform corrosion, localized corrosion, and passivity based on the balance between the dilution ratio of artificial seawater and the concentration of Na2B10O16. The changes in corrosion forms were arranged on a water quality region map. Passivity was maintained by adding 3.7 × 10-2 M or more of Na2B10O16 to artificial seawater with a dilution ratio of 100-fold or more. The criticality control of the fuel debris and corrosion mitigation of the carbon steel components may be achieved simultaneously in the water quality. The prediction of the corrosion form of carbon steel was attempted by the extended Larson-Skold Index (LSI) = ([Cl-] + 2[SO42-])/([HCO3-] + 2[B10O162-]). However, because the passivating action of B10O162- was remarkably stronger than that of HCO3-, the prediction was difficult under the simple addition of equivalent concentrations. The localized corrosion of carbon steel under the addition of Na2B10O16 preferentially occurred from the crevices of the test specimens, as was the case in stainless steel.

49 CFR 192.473 - External corrosion control: Interference currents.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Interference currents. 192.473 Section 192.473 Transportation Other Regulations Relating to Transportation (Continued... for Corrosion Control § 192.473 External corrosion control: Interference currents. (a) Each operator...

49 CFR 193.2304 - Corrosion control overview.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Corrosion control overview. 193.2304 Section 193... GAS FACILITIES: FEDERAL SAFETY STANDARDS Construction § 193.2304 Corrosion control overview. (a... materials specifications from a corrosion control viewpoint and determines that the materials involved will...

49 CFR 192.463 - External corrosion control: Cathodic protection.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Cathodic protection. 192.463 Section 192.463 Transportation Other Regulations Relating to Transportation (Continued... for Corrosion Control § 192.463 External corrosion control: Cathodic protection. (a) Each cathodic...

49 CFR 192.463 - External corrosion control: Cathodic protection.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Cathodic protection. 192.463 Section 192.463 Transportation Other Regulations Relating to Transportation (Continued... for Corrosion Control § 192.463 External corrosion control: Cathodic protection. (a) Each cathodic...

49 CFR 192.473 - External corrosion control: Interference currents.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Interference currents. 192.473 Section 192.473 Transportation Other Regulations Relating to Transportation (Continued... for Corrosion Control § 192.473 External corrosion control: Interference currents. (a) Each operator...

49 CFR 192.463 - External corrosion control: Cathodic protection.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Cathodic protection. 192.463 Section 192.463 Transportation Other Regulations Relating to Transportation (Continued... for Corrosion Control § 192.463 External corrosion control: Cathodic protection. (a) Each cathodic...

49 CFR 193.2304 - Corrosion control overview.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Corrosion control overview. 193.2304 Section 193... GAS FACILITIES: FEDERAL SAFETY STANDARDS Construction § 193.2304 Corrosion control overview. (a... materials specifications from a corrosion control viewpoint and determines that the materials involved will...

49 CFR 193.2304 - Corrosion control overview.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Corrosion control overview. 193.2304 Section 193... GAS FACILITIES: FEDERAL SAFETY STANDARDS Construction § 193.2304 Corrosion control overview. (a... materials specifications from a corrosion control viewpoint and determines that the materials involved will...

49 CFR 192.473 - External corrosion control: Interference currents.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Interference currents. 192.473 Section 192.473 Transportation Other Regulations Relating to Transportation (Continued... for Corrosion Control § 192.473 External corrosion control: Interference currents. (a) Each operator...

49 CFR 193.2304 - Corrosion control overview.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Corrosion control overview. 193.2304 Section 193... GAS FACILITIES: FEDERAL SAFETY STANDARDS Construction § 193.2304 Corrosion control overview. (a... materials specifications from a corrosion control viewpoint and determines that the materials involved will...

49 CFR 192.473 - External corrosion control: Interference currents.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Interference currents. 192.473 Section 192.473 Transportation Other Regulations Relating to Transportation (Continued... for Corrosion Control § 192.473 External corrosion control: Interference currents. (a) Each operator...

49 CFR 192.463 - External corrosion control: Cathodic protection.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Cathodic protection. 192.463 Section 192.463 Transportation Other Regulations Relating to Transportation (Continued... for Corrosion Control § 192.463 External corrosion control: Cathodic protection. (a) Each cathodic...

49 CFR 192.463 - External corrosion control: Cathodic protection.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Cathodic protection. 192.463 Section 192.463 Transportation Other Regulations Relating to Transportation (Continued... for Corrosion Control § 192.463 External corrosion control: Cathodic protection. (a) Each cathodic...

49 CFR 192.473 - External corrosion control: Interference currents.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Interference currents. 192.473 Section 192.473 Transportation Other Regulations Relating to Transportation (Continued... for Corrosion Control § 192.473 External corrosion control: Interference currents. (a) Each operator...

High temperature alkali corrosion of ceramics in coal gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pickrell, G.R.; Sun, T.; Brown, J.J.

1992-02-24

The high temperature alkali corrosion kinetics of SiC have been systematically investigated from 950 to 1100[degrees]C at 0.63 vol % alkali vapor concentration. The corrosion rate in the presence of alkaliis approximately 10[sup 4] to 10[sup 5] times faster than the oxidation rate of SiC in air. The activation energy associated with the alkali corrosion is 406 kJ/mol, indicating a highly temperature-dependent reaction rate. The rate-controlling step of the overall reaction is likely to be the dissolution of silica in the sodium silicate liquid, based on the oxygen diffusivity data.

Real-World Water System Lead and Copper Corrosion Control

EPA Science Inventory

This presentation provides specific background on lead and copper corrosion control chemistry and strategies, and integrates it with other important distribution system corrosion control objectives. Topics covered include: driving force for corrosion (oxidants); impacts of oxida...

Practical Implications from Observed Lead Pipe Scale Mineralogy in a Blended Phosphate Treated System - slides

EPA Science Inventory

Many water utilities in the United States rely on the addition of phosphate-based corrosion inhibitors to optimize their corrosion control and comply with requirements of the Lead and Copper Rule. Orthophosphate is used on the theory of forming low solubility Pb(II)-orthophosphat...

49 CFR 192.479 - Atmospheric corrosion control: General.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Atmospheric corrosion control: General. 192.479... Control § 192.479 Atmospheric corrosion control: General. (a) Each operator must clean and coat each... this section. (b) Coating material must be suitable for the prevention of atmospheric corrosion. (c...

49 CFR 192.481 - Atmospheric corrosion control: Monitoring.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Atmospheric corrosion control: Monitoring. 192.481... Control § 192.481 Atmospheric corrosion control: Monitoring. (a) Each operator must inspect each pipeline or portion of pipeline that is exposed to the atmosphere for evidence of atmospheric corrosion, as...

49 CFR 192.479 - Atmospheric corrosion control: General.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Atmospheric corrosion control: General. 192.479... Control § 192.479 Atmospheric corrosion control: General. (a) Each operator must clean and coat each... this section. (b) Coating material must be suitable for the prevention of atmospheric corrosion. (c...

49 CFR 192.481 - Atmospheric corrosion control: Monitoring.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Atmospheric corrosion control: Monitoring. 192.481... Control § 192.481 Atmospheric corrosion control: Monitoring. (a) Each operator must inspect each pipeline or portion of pipeline that is exposed to the atmosphere for evidence of atmospheric corrosion, as...

49 CFR 192.479 - Atmospheric corrosion control: General.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Atmospheric corrosion control: General. 192.479... Control § 192.479 Atmospheric corrosion control: General. (a) Each operator must clean and coat each... this section. (b) Coating material must be suitable for the prevention of atmospheric corrosion. (c...

49 CFR 192.481 - Atmospheric corrosion control: Monitoring.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Atmospheric corrosion control: Monitoring. 192.481... Control § 192.481 Atmospheric corrosion control: Monitoring. (a) Each operator must inspect each pipeline or portion of pipeline that is exposed to the atmosphere for evidence of atmospheric corrosion, as...

49 CFR 192.465 - External corrosion control: Monitoring.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Monitoring. 192.465... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.465 External corrosion control: Monitoring. (a) Each pipeline that is under cathodic...

49 CFR 192.469 - External corrosion control: Test stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Test stations. 192.469... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.469 External corrosion control: Test stations. Each pipeline under cathodic protection...

49 CFR 195.557 - Which pipelines must have coating for external corrosion control?

Code of Federal Regulations, 2011 CFR

2011-10-01

... corrosion control? 195.557 Section 195.557 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.557 Which pipelines must have coating for external corrosion control? Except bottoms of aboveground breakout tanks, each...

49 CFR 192.469 - External corrosion control: Test stations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Test stations. 192.469... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.469 External corrosion control: Test stations. Each pipeline under cathodic protection...

49 CFR 192.481 - Atmospheric corrosion control: Monitoring.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Atmospheric corrosion control: Monitoring. 192.481... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.481 Atmospheric corrosion control: Monitoring. (a) Each operator must inspect each pipeline...

49 CFR 195.557 - Which pipelines must have coating for external corrosion control?

Code of Federal Regulations, 2012 CFR

2012-10-01

... corrosion control? 195.557 Section 195.557 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.557 Which pipelines must have coating for external corrosion control? Except bottoms of aboveground breakout tanks, each...

49 CFR 192.465 - External corrosion control: Monitoring.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Monitoring. 192.465... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.465 External corrosion control: Monitoring. (a) Each pipeline that is under cathodic...

49 CFR 195.557 - Which pipelines must have coating for external corrosion control?

Code of Federal Regulations, 2014 CFR

2014-10-01

... corrosion control? 195.557 Section 195.557 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.557 Which pipelines must have coating for external corrosion control? Except bottoms of aboveground breakout tanks, each...

49 CFR 192.465 - External corrosion control: Monitoring.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Monitoring. 192.465... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.465 External corrosion control: Monitoring. (a) Each pipeline that is under cathodic...

49 CFR 192.465 - External corrosion control: Monitoring.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Monitoring. 192.465... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.465 External corrosion control: Monitoring. (a) Each pipeline that is under cathodic...

49 CFR 192.469 - External corrosion control: Test stations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Test stations. 192.469... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.469 External corrosion control: Test stations. Each pipeline under cathodic protection...

49 CFR 195.557 - Which pipelines must have coating for external corrosion control?

Code of Federal Regulations, 2013 CFR

2013-10-01

... corrosion control? 195.557 Section 195.557 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.557 Which pipelines must have coating for external corrosion control? Except bottoms of aboveground breakout tanks, each...

49 CFR 192.469 - External corrosion control: Test stations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Test stations. 192.469... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.469 External corrosion control: Test stations. Each pipeline under cathodic protection...

49 CFR 192.469 - External corrosion control: Test stations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Test stations. 192.469... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.469 External corrosion control: Test stations. Each pipeline under cathodic protection...

49 CFR 195.557 - Which pipelines must have coating for external corrosion control?

Code of Federal Regulations, 2010 CFR

2010-10-01

... corrosion control? 195.557 Section 195.557 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.557 Which pipelines must have coating for external corrosion control? Except bottoms of aboveground breakout tanks, each...

Complexity of Products of Tungsten Corrosion: Comparison of the 3D Pourbaix Diagrams with the Experimental Data

NASA Astrophysics Data System (ADS)

Nave, Maryana I.; Kornev, Konstantin G.

2017-03-01

Tungsten is one of the most attractive metals in applications where materials are subject to high temperature and strong fields. However, in harsh aqueous environment, tungsten is prone to corrosion. Control of tungsten corrosion in aqueous solutions is a challenging task: as a transition metal, tungsten is able to produce a vast variety of oxides and hydrates. To reveal the thermodynamic pathway of corrosion at different conditions, the 3D Pourbaix diagrams relating the reduction potential, pH, and concentration of different tungsten-based compounds were constructed. These diagrams allow one to identify the most thermodynamically stable tungsten-based compounds. The 3D Pourbaix diagrams were used to explain different regimes of anodic dissolution of tungsten in aqueous solutions of potassium hydroxide.

49 CFR 192.476 - Internal corrosion control: Design and construction of transmission line.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Internal corrosion control: Design and... STANDARDS Requirements for Corrosion Control § 192.476 Internal corrosion control: Design and construction of transmission line. (a) Design and construction. Except as provided in paragraph (b) of this...

49 CFR 192.476 - Internal corrosion control: Design and construction of transmission line.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Internal corrosion control: Design and... STANDARDS Requirements for Corrosion Control § 192.476 Internal corrosion control: Design and construction of transmission line. (a) Design and construction. Except as provided in paragraph (b) of this...

49 CFR 192.476 - Internal corrosion control: Design and construction of transmission line.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Internal corrosion control: Design and... STANDARDS Requirements for Corrosion Control § 192.476 Internal corrosion control: Design and construction of transmission line. (a) Design and construction. Except as provided in paragraph (b) of this...

49 CFR 192.476 - Internal corrosion control: Design and construction of transmission line.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Internal corrosion control: Design and... STANDARDS Requirements for Corrosion Control § 192.476 Internal corrosion control: Design and construction of transmission line. (a) Design and construction. Except as provided in paragraph (b) of this...

49 CFR 192.476 - Internal corrosion control: Design and construction of transmission line.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Internal corrosion control: Design and... STANDARDS Requirements for Corrosion Control § 192.476 Internal corrosion control: Design and construction of transmission line. (a) Design and construction. Except as provided in paragraph (b) of this...

40 CFR 141.82 - Description of corrosion control treatment requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Description of corrosion control... § 141.82 Description of corrosion control treatment requirements. Each system shall complete the corrosion control treatment requirements described below which are applicable to such system under § 141.81...

40 CFR 141.82 - Description of corrosion control treatment requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Description of corrosion control... § 141.82 Description of corrosion control treatment requirements. Each system shall complete the corrosion control treatment requirements described below which are applicable to such system under § 141.81...

40 CFR 141.82 - Description of corrosion control treatment requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Description of corrosion control... § 141.82 Description of corrosion control treatment requirements. Each system shall complete the corrosion control treatment requirements described below which are applicable to such system under § 141.81...

40 CFR 141.82 - Description of corrosion control treatment requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Description of corrosion control... § 141.82 Description of corrosion control treatment requirements. Each system shall complete the corrosion control treatment requirements described below which are applicable to such system under § 141.81...

40 CFR 141.82 - Description of corrosion control treatment requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Description of corrosion control... § 141.82 Description of corrosion control treatment requirements. Each system shall complete the corrosion control treatment requirements described below which are applicable to such system under § 141.81...

Environmentally Compatible Vapor-Phase Corrosion Inhibitor for Space Shuttle Hardware

NASA Technical Reports Server (NTRS)

Novak, Howard L.; Hall, Phillip B.

2003-01-01

USA-SRB Element is responsible for the assembly and refurbishment of the non-motor components of the SRB as part of Space Shuttle. Thrust Vector Control (TVC) frames structurally support components of the TVC system located in the aft skirt of the SRB. TVC frames are exposed to the seacoast environment after refurbishment and, also, to seawater immersion after splashdown, and during tow-back to CCAFS-Hangar AF refurbishment facilities. During refurbishment operations it was found that numerous TVC frames were experiencing internal corrosion and coating failures, both from salt air and seawater intrusions. Inspectors using borescopes would visually examine the internal cavities of the complicated aluminum alloy welded tubular structure. It was very difficult for inspectors to examine cavity corners and tubing intersections and particularly, to determine the extent of the corrosion and coating anomalies. Physical access to TVC frame internal cavities for corrosion removal and coating repair was virtually impossible, and an improved method using a Liquid (water based) Vapor-phase Corrosion Inhibitor (LVCI) for preventing initiation of new corrosion, and mitigating and/or stopping existing corrosion growth was recommended in lieu of hazardous paint solvents and high VOC / solvent based corrosion inhibitors. In addition, the borescopic inspection method used to detect corrosion, and/or coating anomalies had severe limitations because of part geometry, and an improved non-destructive inspection (NDI) method using Neutron Radiography (N-Ray) was also recommended.

Environmentally Compatible Vapor-Phase Corrosion Inhibitor for Space Shuttle Hardware

NASA Technical Reports Server (NTRS)

Novak, Howard L.; Hall, Phillip B.; Martin, David (Technical Monitor)

2002-01-01

USA-SRB Element is responsible for the assembly and refurbishment of the non-motor components of the SRB as part of Space Shuttle. Thrust Vector Control (TVC) frames structurally support components of the TVC system located in the aft skirt of the SRB (Solid Rocket Booster). TVC frames are exposed to the seacoast environment after refurbishment and, also, to seawater immersion after splashdown, and during tow-back to CCAFS-Hangar AF refurbishment facilities. During refurbishment operations it was found that numerous TVC frames were experiencing internal corrosion and coating failures, both from salt air and seawater intrusions. Inspectors using borescopes would visually examine the internal cavities of the complicated aluminum alloy welded tubular structure. It was very difficult for inspectors to examine cavity corners and tubing intersections and particularly. to determine the extent of the corrosion and coating anomalies. Physical access to TVC frame internal cavities for corrosion removal and coating repair was virtually impossible, and an improved method using a Liquid (water based) Vapor-phase Corrosion Inhibitor (LVCI) for preventing initiation of new corrosion, and mitigating and/or stopping existing corrosion growth was recommended in lieu of hazardous paint solvents and high VOC/solvent based corrosion inhibitors. In addition, the borescopic inspection method used to detect corrosion, and/or coating anomalies had severe limitations because of part geometry, and an improved non-destructive inspection (NDI) method using Neutron Radiography (N-Ray) was also recommended.

Environmentally Compatible Vapor-Phase Corrosion Inhibitor for Space Shuttle Hardware

NASA Technical Reports Server (NTRS)

Novak, Howard L.; Hall, Phillip B.; McCool, Alex (Technical Monitor)

2001-01-01

USA-SRB Element is responsible for the assembly and refurbishment of the non-motor components of the SRB as part of Space Shuttle. Thrust Vector Control (TVC) frames structurally support components of the TVC system located in the aft skirt of the SRB. TVC frames are exposed to the seacoast environment after refurbishment and, also, to seawater immersion after splashdown, and during tow-back to CCAFS-Hangar AF refurbishment facilities. During refurbishment operations it was found that numerous TVC frames were experiencing internal corrosion and coating failures, both from salt air and seawater intrusions. Inspectors using borescopes would visually examine the internal cavities of the complicated aluminum alloy welded tubular structure. It was very difficult for inspectors to examine cavity corners and tubing intersections and particularly, to determine the extent of the corrosion and coating anomalies. Physical access to TVC frame internal cavities for corrosion removal and coating repair was virtually impossible, and an improved method using a Liquid (water based) Vapor-phase Corrosion Inhibitor (LVCI) for preventing initiation of new corrosion, and mitigating and/or stopping existing corrosion growth was recommended in lieu of hazardous paint solvents and high VOC/solvent based corrosion inhibitors. In addition, the borescopic inspection method used to detect corrosion, and/or coating anomalies had severe limitations because of part geometry, and an improved non-destructive inspection (NDI) method using Neutron Radiography (N-Ray) was also recommended.

49 CFR 193.2627 - Atmospheric corrosion control.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Atmospheric corrosion control. 193.2627 Section... LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2627 Atmospheric corrosion control. Each exposed component that is subject to atmospheric corrosive attack must be protected from...

49 CFR 193.2627 - Atmospheric corrosion control.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Atmospheric corrosion control. 193.2627 Section... LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2627 Atmospheric corrosion control. Each exposed component that is subject to atmospheric corrosive attack must be protected from...

49 CFR 193.2627 - Atmospheric corrosion control.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Atmospheric corrosion control. 193.2627 Section... LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2627 Atmospheric corrosion control. Each exposed component that is subject to atmospheric corrosive attack must be protected from...

49 CFR 193.2635 - Monitoring corrosion control.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Monitoring corrosion control. 193.2635 Section 193... GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2635 Monitoring corrosion control. Corrosion protection provided as required by this subpart must be periodically monitored to give early...

49 CFR 193.2635 - Monitoring corrosion control.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Monitoring corrosion control. 193.2635 Section 193... GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2635 Monitoring corrosion control. Corrosion protection provided as required by this subpart must be periodically monitored to give early...

49 CFR 193.2635 - Monitoring corrosion control.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Monitoring corrosion control. 193.2635 Section 193... GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2635 Monitoring corrosion control. Corrosion protection provided as required by this subpart must be periodically monitored to give early...

49 CFR 193.2635 - Monitoring corrosion control.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Monitoring corrosion control. 193.2635 Section 193... GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2635 Monitoring corrosion control. Corrosion protection provided as required by this subpart must be periodically monitored to give early...

Corrosion behavior of pristine and added MgB2 in Phosphate Buffered Saline Solution

NASA Astrophysics Data System (ADS)

Batalu, D.; Bojin, D.; Ghiban, B.; Aldica, G.; Badica, P.

2012-09-01

We have obtained by Spark Plasma Sintering (SPS), dense samples of MgB2 added with Ho2O3. Starting composition was (MgB2)0.975(HoO1.5)0.025 and we used addition powders with an average particle size below and above 100 nm. For Mg, pristine and added MgB2 samples we measured potentiodynamic polarization curves in Phosphate Buffered Saline (PBS) solution media at room temperature. MgB2 based composites show corrosion/ degradation effects. This behavior is in principle similar to Mg based alloys in the same media. Our work suggests that the different morphologies and phase compositions of the SPS-ed samples influence the interaction with corrosion medium; hence additions can play an important role in controlling the corrosion rate. Pristine MgB2 show a significant improvement of the corrosion resistance, if compared with Mg. The best corrosion resistance is obtained for pristine MgB2, followed by MgB2 with nano-Ho2O3 and μ-Ho2O3 additions.

49 CFR 195.561 - When must I inspect pipe coating used for external corrosion control?

Code of Federal Regulations, 2010 CFR

2010-10-01

... corrosion control? 195.561 Section 195.561 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.561 When must I inspect pipe coating used for external corrosion control? (a) You must inspect all external pipe coating...

49 CFR 192.471 - External corrosion control: Test leads.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Test leads. 192.471... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.471 External corrosion control: Test leads. (a) Each test lead wire must be connected to the...

49 CFR 192.471 - External corrosion control: Test leads.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Test leads. 192.471... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.471 External corrosion control: Test leads. (a) Each test lead wire must be connected to the...

49 CFR 195.561 - When must I inspect pipe coating used for external corrosion control?

Code of Federal Regulations, 2011 CFR

2011-10-01

... corrosion control? 195.561 Section 195.561 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.561 When must I inspect pipe coating used for external corrosion control? (a) You must inspect all external pipe coating...

49 CFR 195.561 - When must I inspect pipe coating used for external corrosion control?

Code of Federal Regulations, 2013 CFR

2013-10-01

... corrosion control? 195.561 Section 195.561 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.561 When must I inspect pipe coating used for external corrosion control? (a) You must inspect all external pipe coating...

49 CFR 195.561 - When must I inspect pipe coating used for external corrosion control?

Code of Federal Regulations, 2014 CFR

2014-10-01

... corrosion control? 195.561 Section 195.561 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.561 When must I inspect pipe coating used for external corrosion control? (a) You must inspect all external pipe coating...

49 CFR 195.561 - When must I inspect pipe coating used for external corrosion control?

Code of Federal Regulations, 2012 CFR

2012-10-01

... corrosion control? 195.561 Section 195.561 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.561 When must I inspect pipe coating used for external corrosion control? (a) You must inspect all external pipe coating...

Corrosion Control in the Aerospace Industry

NASA Technical Reports Server (NTRS)

Calle, Luz Marina; Li, Wenyan; Buhrow, Jerry W.; Johnsey, Marissa N.

2016-01-01

Nearly all metals and their alloys are subject to corrosion that causes them to lose their structural integrity or other critical functionality. It is essential to detect corrosion when it occurs, and preferably at its early stage, so that action can be taken to avoid structural damage or loss of function. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional, smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to indicate it and control it..

Corrosion Control through a Better Understanding of the Metallic Substrate/Organic Coating/Interface.

DTIC Science & Technology

1984-01-01

Gerhard Brauer, and Henry Leidheiser, Jr., Nuclear Instruments and Methods 199, 353-57 (1982). "Cobalt and Nickel Cations as Corrosion Inhibitors for...2, 583-603 (1983). "Characterization of Solid Surfaces by Wet Chemical Methods ," F. M. Fowkes, ACS Symp. Ser. 199, 69-88 (1982). "New Concepts of...from these nucleation sites. A second method being used to understand better the initial stages of the corrosion process is based on the change in

Characterization of Encapsulated Corrosion Inhibitors for Environmentally Friendly Smart Coatings

NASA Technical Reports Server (NTRS)

Pearman, B. P.; Calle, L. M.; Zhang, X.; Li, W.; Buhrow, J. W.; Johnsey, M. N.; Montgomery, E. L.; Fitzpatrick, L.; Surma, J. M.

2015-01-01

The NASA Kennedy Space Center's Corrosion Technology Lab at the Kennedy Space Center in Florida, U.S.A. has been developing multifunctional smart coatings based on the microencapsulation of environmentally friendly corrosion indicators, inhibitors and self-healing agents. This allows the incorporation of autonomous corrosion control functionalities, such as corrosion detection and inhibition as well as the self-healing of mechanical damage, into coatings. This paper presents technical details on the characterization of inhibitor-containing particles and their corrosion inhibitive effects using electrochemical and mass loss methods. Three organic environmentally friendly corrosion inhibitors were encapsulated in organic microparticles that are compatible with desired coatings. The release of the inhibitors from the microparticles in basic solution was studied. Fast release, for immediate corrosion protection, as well as long-term release for continued protection, was observed. The inhibition efficacy of the inhibitors, incorporated directly and in microparticles, on carbon steel was evaluated. Polarization curves and mass loss measurements showed that, in the case of 2MBT, its corrosion inhibition effectiveness was greater when it was delivered from microparticles.

Protection of bronze artefacts through polymeric coatings based on nanocarriers filled with corrosion inhibitors

NASA Astrophysics Data System (ADS)

de Luna, Martina Salzano; Buonocore, Giovanna; Di Carlo, Gabriella; Giuliani, Chiara; Ingo, Gabriel M.; Lavorgna, Marino

2016-05-01

Protective coatings based on polymers synthesized from renewable sources (chitosan or an amorphous vinyl alcohol based polymer) have been prepared for the protection of bronze artifacts from corrosion. Besides acting as an effective barrier against corrosive species present in the environment, the efficiency of the coatings has been improved by adding corrosion inhibitor compounds (benzotriazole or mercaptobenzothiazole) to the formulations. The liquid medium of the formulations has been carefully selected looking at maximizing the wettability on the bronze substrate and optimizing the solvent evaporation rate. The minimum amount of inhibitor compounds has been optimized by performing accelerated corrosion tests on coated bronze substrates. The inhibitors have been directly dissolved in the coating-forming solutions and/or introduced by means of nanocarriers, which allow to control the release kinetics. The free dissolved inhibitor molecules immediately provide a sufficient protection against corrosion. On the other hand, the inhibitor molecules contained in the nanocarriers serve as long-term reservoir, which can be activated by external corrosion-related stimuli in case of particularly severe conditions. Particular attention has been paid to other features which affect the coating performances. Specifically, the adhesion of the protective polymer layer to the bronze substrate has been assessed, as well as its permeability properties and transparency, the latter being a fundamental feature of protective coating for cultural heritages. Finally, the protective efficiency of the produced smart coatings has been assessed through accelerated corrosion tests.

Stress Corrosion Evaluation of Various Metallic Materials for the International Space Station Water Recycling System

NASA Technical Reports Server (NTRS)

Torres, P. D.

2015-01-01

A stress corrosion evaluation was performed on Inconel 625, Hastelloy C276, titanium commercially pure (TiCP), Ti-6Al-4V, Ti-6Al-4V extra low interstitial, and Cronidur 30 steel as a consequence of a change in formulation of the pretreatment for processing the urine in the International Space Station Environmental Control and Life Support System Urine Processing Assembly from a sulfuric acid-based to a phosphoric acid-based solution. The first five listed were found resistant to stress corrosion in the pretreatment and brine. However, some of the Cronidur 30 specimens experienced reduction in load-carrying ability.

Al-based anti-corrosion and T-permeation barrier development for future DEMO blankets

NASA Astrophysics Data System (ADS)

Krauss, W.; Konys, J.; Holstein, N.; Zimmermann, H.

2011-10-01

In the Helium-Cooled-Liquid-Lead (HCLL) design of Test-Blanket-Modules (TBM's) for a future fusion power plant Pb-15.7Li is used as liquid breeder which is in direct contact with the structure material, e.g. EUROFER steel. Compatibility testing showed that high corrosion attack appears and that the dissolved steel components form precipitates with a high risk of system blockages. A reliable operation needs coatings as corrosion barriers. The earlier developed Hot-Dip Aluminisation (HDA) process has shown that Al-based scales can act as anti-corrosion as well as T-permeation barriers. Meanwhile two advanced electro-chemically based processes for deposition of Al-scales were successfully developed. The first (ECA = Electro-Chemical Al-deposition) is working with an organic electrolyte and the second one (ECX = Electro-Chemical-X-metal-deposition) is based on ionic liquids. Coatings in the μm-range were deposited homogeneously with exact controllable thicknesses. Metallurgical investigations showed the successful generation of protective scales and compatibility testing demonstrated the barrier function.

49 CFR 193.2627 - Atmospheric corrosion control.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Atmospheric corrosion control. 193.2627 Section... LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2627 Atmospheric corrosion... atmospheric corrosion by— (a) Material that has been designed and selected to resist the corrosive atmosphere...

Control of corrosive bacterial community by bronopol in industrial water system.

PubMed

Narenkumar, Jayaraman; Ramesh, Nachimuthu; Rajasekar, Aruliah

2018-01-01

Ten aerobic corrosive bacterial strains were isolated from a cooling tower water system (CWS) which were identified based on the biochemical characterization and 16S rRNA gene sequencing. Out of them, dominant corrosion-causing bacteria, namely, Bacillus thuringiensis EN2, Terribacillus aidingensis EN3, and Bacillus oleronius EN9, were selected for biocorrosion studies on mild steel 1010 (MS) in a CWS. The biocorrosion behaviour of EN2, EN3, and EN9 strains was studied using immersion test (weight loss method), electrochemical analysis, and surface analysis. To address the corrosion problems, an anti-corrosive study using a biocide, bronopol was also demonstrated. Scanning electron microscopy and Fourier-transform infrared spectroscopy analyses of the MS coupons with biofilm developed after exposure to CWS confirmed the accumulation of extracellular polymeric substances and revealed that biofilms was formed as microcolonies, which subsequently cause pitting corrosion. In contrast, the biocide system, no pitting type of corrosion, was observed and weight loss was reduced about 32 ± 2 mg over biotic system (286 ± 2 mg). FTIR results confirmed the adsorption of bronopol on the MS metal surface as protective layer (co-ordination of NH 2 -Fe 3+ ) to prevent the biofilm formation and inhibit the corrosive chemical compounds and thus led to reduction of corrosion rate (10 ± 1 mm/year). Overall, the results from WL, EIS, SEM, XRD, and FTIR concluded that bronopol was identified as effective biocide and corrosion inhibitor which controls the both chemical and biocorrosion of MS in CWS.

Atomic layer deposited ZrO2 nanofilm on Mg-Sr alloy for enhanced corrosion resistance and biocompatibility.

PubMed

Yang, Qiuyue; Yuan, Wei; Liu, Xiangmei; Zheng, Yufeng; Cui, Zhenduo; Yang, Xianjin; Pan, Haobo; Wu, Shuilin

2017-08-01

The biodegradability and good mechanical property of magnesium alloys make them potential biomedical materials. However, their rapid corrosion rate in the human body's environment impairs these advantages and limits their clinical use. In this work, a compact zirconia (ZrO 2 ) nanofilm was fabricated on the surface of a magnesium-strontium (Mg-Sr) alloy by the atomic layer deposition (ALD) method, which can regulate the thickness of the film precisely and thus also control the corrosion rate. Corrosion tests reveal that the ZrO 2 film can effectively reduce the corrosion rate of Mg-Sr alloys that is closely related to the thickness of the film. The cell culture test shows that this kind of ZrO 2 film can also enhance the activity and adhesion of osteoblasts on the surfaces of Mg-Sr alloys. The significance of the current work is to develop a zirconia nanofilm on biomedical MgSr alloy with controllable thickness precisely through atomic layer deposition technique. By adjusting the thickness of nanofilm, the corrosion rate of Mg-Sr alloy can be modulated, thereafter, the degradation rate of Mg-based alloys can be controlled precisely according to actual clinical requirement. In addition, this zirconia nanofilm modified Mg-Sr alloys show excellent biocompatibility than the bare samples. Hence, this work provides a new surface strategy to control the degradation rate while improving the biocompatibility of substrates. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

DOUBLE SHELL TANK (DST) INTEGRITY PROJECT HIGH LEVEL WASTE CHEMISTRY OPTIMIZATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

WASHENFELDER DJ

2008-01-22

The U.S. Department of Energy's Office (DOE) of River Protection (ORP) has a continuing program for chemical optimization to better characterize corrosion behavior of High-Level Waste (HLW). The DOE controls the chemistry in its HLW to minimize the propensity of localized corrosion, such as pitting, and stress corrosion cracking (SCC) in nitrate-containing solutions. By improving the control of localized corrosion and SCC, the ORP can increase the life of the Double-Shell Tank (DST) carbon steel structural components and reduce overall mission costs. The carbon steel tanks at the Hanford Site are critical to the mission of safely managing stored HLWmore » until it can be treated for disposal. The DOE has historically used additions of sodium hydroxide to retard corrosion processes in HLW tanks. This also increases the amount of waste to be treated. The reactions with carbon dioxide from the air and solid chemical species in the tank continually deplete the hydroxide ion concentration, which then requires continued additions. The DOE can reduce overall costs for caustic addition and treatment of waste, and more effectively utilize waste storage capacity by minimizing these chemical additions. Hydroxide addition is a means to control localized and stress corrosion cracking in carbon steel by providing a passive environment. The exact mechanism that causes nitrate to drive the corrosion process is not yet clear. The SCC is less of a concern in the newer stress relieved double shell tanks due to reduced residual stress. The optimization of waste chemistry will further reduce the propensity for SCC. The corrosion testing performed to optimize waste chemistry included cyclic potentiodynamic volarization studies. slow strain rate tests. and stress intensity factor/crack growth rate determinations. Laboratory experimental evidence suggests that nitrite is a highly effective:inhibitor for pitting and SCC in alkaline nitrate environments. Revision of the corrosion control strategies to a nitrite-based control, where there is no constant depletion mechanism as with hydroxide, should greatly enhance tank lifetime, tank space availability, and reduce downstream reprocessing costs by reducing chemical addition to the tanks.« less

REASONS FOR CORROSION CONTROL OTHER THAN THE LEAD AND COPPER RULE

EPA Science Inventory

A corrosion control program designed to accommodate all distribution system materials, as well as lead and copper, will produce significant benefits that are not always related to corrosion in an obvious way. Essential components of a good corrosion control program are the selec...

Smart Multifunctional Coatings for Corrosion Detection and Control in the Aerospace Industry

NASA Technical Reports Server (NTRS)

Calle, Luz Marina

2015-01-01

Nearly all metals and their alloys are subject to corrosion that causes them to lose their structural integrity or other critical functionality. It is essential to detect corrosion when it occurs, and preferably at its early stage, so that action can be taken to avoid structural damage or loss of function. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional, smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to indicate it and control it.

Wear and corrosion behaviour of Al2O3-TiO2 coatings produced by flame thermal projection

NASA Astrophysics Data System (ADS)

Forero-Duran, M.; Dulce-Moreno, H. J.; Ferrer-Pacheco, M.; Vargas-Galvis, F.

2017-12-01

Evaluated the wear resistance and the coatings corrosion behaviour of Al2O3-TiO2 prepared by thermal spraying by flame on AISI 1020 carbon steel substrates, previously coated with an alloy base Ni. For this purpose, were controlled parameters of thermal spraying and the use of powders of similar but different chemical composition is taken as a variable commercial reference for ceramic coating. SEM images allowed to know the morphology of the powders and coatings. Electrochemical techniques (Tafel) were applied to evaluate the protection against corrosion. Coatings were tested for wear with a tribometer configuration bola-disco. It was determined that the phases present in coatings are directly relate to the behaviour against corrosion and wear them. Keywords: wear, corrosion, thermal imaging.

Image analysis of corrosion pit initiation on ASTM type A240 stainless steel and ASTM type A 1008 carbon steel

NASA Astrophysics Data System (ADS)

Nine, H. M. Zulker

The adversity of metallic corrosion is of growing concern to industrial engineers and scientists. Corrosion attacks metal surface and causes structural as well as direct and indirect economic losses. Multiple corrosion monitoring tools are available although those are time-consuming and costly. Due to the availability of image capturing devices in today's world, image based corrosion control technique is a unique innovation. By setting up stainless steel SS 304 and low carbon steel QD 1008 panels in distilled water, half-saturated sodium chloride and saturated sodium chloride solutions and subsequent RGB image analysis in Matlab, in this research, a simple and cost-effective corrosion measurement tool has identified and investigated. Additionally, the open circuit potential and electrochemical impedance spectroscopy results have been compared with RGB analysis to gratify the corrosion. Additionally, to understand the importance of ambiguity in crisis communication, the communication process between Union Carbide and Indian Government regarding the Bhopal incident in 1984 was analyzed.

The Application of Electrochemical and Surface Analysis Approaches to Studying Copper Corrosion in Water: Fundamentals, Limitations, and Examples

EPA Science Inventory

Corrosion control is a concern for many drinking water utilities. The Lead and Copper Rule established a regulatory need to maintain a corrosion control program. Other corrosion-related issues such as “red” water resulting from excessive iron corrosion and copper pinhole leaks ...

Corrosion assessment and enhanced biocompatibility analysis of biodegradable magnesium-based alloys

NASA Astrophysics Data System (ADS)

Pompa, Luis Enrique

Magnesium alloys have raised immense interest to many researchers because of its evolution as a new third generation material. Due to their biocompatibility, density, and mechanical properties, magnesium alloys are frequently reported as prospective biodegradable implant materials. Moreover, magnesium based alloys experience a natural phenomena to biodegrade in aqueous solutions due to its corrosive activity, which is excellent for orthopedic and cardiovascular applications. However, major concerns with such alloys are fast and non-uniform corrosion degradation. Controlling the degradation rate in the physiological environment determines the success of an implant. In this investigation, three grades of magnesium alloys: AZ31B, AZ91E and ZK60A were studied for their corrosion resistance and biocompatibility. Scanning electron microscopy, energy dispersive spectroscopy, atomic force microscopy and contact angle meter are used to study surface morphology, chemistry, roughness and wettability, respectively. Additionally, the cytotoxicity of the leached metal ions was evaluated by a tetrazolium based bio-assay, MTS.

First-Principles Approach to Model Electrochemical Reactions: Understanding the Fundamental Mechanisms behind Mg Corrosion

NASA Astrophysics Data System (ADS)

Surendralal, Sudarsan; Todorova, Mira; Finnis, Michael W.; Neugebauer, Jörg

2018-06-01

Combining concepts of semiconductor physics and corrosion science, we develop a novel approach that allows us to perform ab initio calculations under controlled potentiostat conditions for electrochemical systems. The proposed approach can be straightforwardly applied in standard density functional theory codes. To demonstrate the performance and the opportunities opened by this approach, we study the chemical reactions that take place during initial corrosion at the water-Mg interface under anodic polarization. Based on this insight, we derive an atomistic model that explains the origin of the anodic hydrogen evolution.

Release Properties and Electrochemical Characterization of Encapsulated Corrosion Inhibitors for Environmentally Friendly Smart Coatings

NASA Technical Reports Server (NTRS)

Pearman, B. P.; Calle, L. M.; Zhang, X.; Li, W.; Buhrow, J. W.; Johnsey, M. N.; Montgomery, E. L.; Fitzpatrick, L.; Surma, J. M.

2015-01-01

The NASA Kennedy Space Center's Corrosion Technology Lab at the Kennedy Space Center in Florida, U.S.A. has been developing multifunctional smart coatings based on the microencapsulation of environmentally friendly corrosion indicators, inhibitors and self-healing agents. This allows for the incorporation of autonomous corrosion control functionalities, such as corrosion detection and inhibition as well as the self-healing of mechanical damage, into coatings. This paper presents technical details on the characterization of inhibitor-containing particles and their corrosion inhibitive effects using electrochemical and mass loss methods. Three organic environmentally friendly corrosion inhibitors were encapsulated in organic microparticles that are compatible with desired coatings. The total inhibitor content and the release of one of the inhibitors from the microparticles in basic solution was measured. Particles with inhibitor contents of up 60 wt% were synthesized. Fast release, for immediate corrosion protection, as well as long-term release for continued protection, was observed. The inhibition efficacy of the inhibitors, both as the pure materials and in microparticles, on carbon steel was evaluated. Polarization curves and mass loss measurements showed that, in the case of 2MBT, its corrosion inhibition effectiveness was greater when it was delivered from microparticles.

Smart Coatings for Corrosion Protection

NASA Technical Reports Server (NTRS)

Calle, Luz Marina; Li, Wendy; Buhrow, Jerry W.; Johnsey, Marissa N.

2016-01-01

Nearly all metals and their alloys are subject to corrosion that causes them to lose their structural integrity or other critical functionality. It is essential to detect corrosion when it occurs, and preferably at its early stage, so that action can be taken to avoid structural damage or loss of function. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional, smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to indicate it and control it.

49 CFR 195.583 - What must I do to monitor atmospheric corrosion control?

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false What must I do to monitor atmospheric corrosion... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.583 What must I do to monitor atmospheric corrosion control? (a) You must inspect each pipeline or portion of pipeline that is...

Adsorption and inhibitive properties of a Schiff base for the corrosion control of carbon steel in saline water.

PubMed

Samide, Adriana; Tutunaru, Bogdan

2011-01-01

A Schiff base, namely N-(2-hydroxybenzylidene) thiosemicarbazide (HBTC), was investigated as inhibitor for carbon steel in saline water (SW) using electrochemical measurements such as: potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The morphology of the surfaces before and after corrosion was examined by Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM/EDS). The results showed that HBTC acts as corrosion inhibitor in SW by suppressing simultaneously the cathodic and anodic processes via adsorption on the surface which followed the Langmuir adsorption isotherm; the polarization resistance (R(p)) and inhibition efficiency (IE) increased with each HBTC concentration increase. SEM/EDS analysis showed at this stage that the main product of corrosion is a non-stoichiometric amorphous Fe(3+) oxyhydroxide, consisting of a mixture of Fe(3+) oxyhydroxides, α-FeOOH and/or γ-FeOOH, α-FeOOH/γ-FeOOH and Fe(OH)(3).

Effect of fluid flow, pH and tobacco extracts concentration as organic inhibitors to corrosion characteristics of AISI 1045 steel in 3.5% NaCl environment containing CO2 gas

NASA Astrophysics Data System (ADS)

Kurniawan, Budi Agung; Pratiwi, Vania Mitha; Ahmadi, Nafi'ul Fikri

2018-04-01

Corrosion become major problem in most industries. In the oil and gas company, corrosion occurs because of reaction between steel and chemical species inside crude oil. Crude oil or nature gas provide corrosive species, such as CO2, O2, H2S and so on. Fluid containing CO2 gas causes CO2 corrosion which attack steel as well as other corrosion phenomena. This CO2 corrosion commonly called as sweet environment and produce FeCO3 as corrosion products. Fluid flow factor in pipelines during the oil and gas transportation might increase the rate of corrosion itself. Inhibitor commonly use used as corrosion protection because its simplicity in usage. Nowadays, organic inhibitor become main issue in corrosion protection because of biodegradable, low cost, and environmental friendly. This research tried to use tobacco leaf extract as organic inhibitor to control corrosion in CO2 environment. The electrolyte solution used was 3.5% NaCl at pH 4 and pH 7. Weight loss test results showed that the lowest corrosion rate was reach at 132.5 ppm inhibitor, pH 7 and rotational speed of 150 rpm with corrosion rate of 0.091 mm/y. While at pH 4, the lowest corrosion rate was found at rotational speed of 150 rpm with inhibitor concentration of 265 ppm and corrosion rate of 0.327 mm/y. FTIR results indicate the presence of nicotine functional groups on the steel surface. However, based on corrosion rate, it is believed that corrosion occurs, and FeCO3 was soluble in electrolyte. Tobacco leaf extract inhibitors worked by a physisorption mechanism, where tobacco inhibitors formed thin layer on the steel surface.

A New Maraging Stainless Steel with Excellent Strength-Toughness-Corrosion Synergy.

PubMed

Tian, Jialong; Wang, Wei; Babar Shahzad, M; Yan, Wei; Shan, Yiyin; Jiang, Zhouhua; Yang, Ke

2017-11-10

A new maraging stainless steel with superior strength-toughness-corrosion synergy has been developed based on an innovative concept of alloy design. The high strength-toughness combination is achieved by forming dispersive nano-sized intermetallic compounds in the soft lath martensitic matrix with a slight amount of residual austenite. The good corrosion resistance is guaranteed by exactly controlling the Co content based on understanding the synergistic effect between Co and Cr. The fine structure characteristics of two dominant strengthening precipitations including Ni₃Ti and Mo-rich phases were finely characterized associated with transmission electron microscope (TEM) and atom probe tomography (APT) analyses. The relationship among microstructure, strength and toughness is discussed. The precipitation mechanism of different precipitates in the new maraging stainless steel is revealed based on the APT analysis.

The Mineralogy of Microbiologically Influenced Corrosion

DTIC Science & Technology

2015-01-01

cathodically active). The biomineralization rate and the corrosion current control oxide accumulation. Localized corrosion current that exceeds the... phosphate ). Localized corrosion would not readily occur unless Cl- was the predominant anion in the medium. They concluded that the Cl- concentration...transforms into goethite and/or hematite over time. For mild steel corrosion under anodic control , manganese oxides elevate con-osion current, but will

77 FR 46940 - Airworthiness Directives; Glasflugel Gliders

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-07

... condition as corrosion damage to the elevator control rod that could lead to failure of the elevator control... into the elevator control rod through a control bore hole and resulted in corrosion damage. The investigation concluded as well that the corrosion cannot be detected from outside the elevator control rod...

Ca2+-exchange in layered zirconium orthophosphate, α-ZrP: Chemical study and potential application for zinc corrosion inhibition

NASA Astrophysics Data System (ADS)

Bouali, Imane; Rocca, Emmanuel; Veys-Renaux, Delphine; Rhouta, Benaissa; Khalil, Aziza; Aït Aghzzaf, Ahmed

2017-11-01

The control of the corrosion phenomenon occurring at the metal interface requires the development of new non-toxic anticorrosion additives. For this purpose, zirconium orthophosphate compounds (Zr(HPO4)2,H2O noted α-ZrP) were synthesized by both hydrothermal and refluxing methods The Ca2+-cationic exchange in the layered structure is kinetically favoured by low crystallinity of α-ZrP synthesized by refluxing process, and leads to the formation of CaZr(PO4)2,4H2O, noted Ca2+-ZrP. The H+/Ca2+ exchange mechanism is mainly triggered by acid-base considerations, and especially the pKa of α-ZrP/Ca2+-ZrP acid-base couple (evaluated to 2.5). Both compounds are acidic compounds by internal exchangeable H+ for α-ZrP and surface protons for Ca2+-ZrP, and can be used as potential inhibitors of zinc corrosion. Electrochemical measurements show that Ca2+-ZrP compounds dispersed in the NaCl electrolyte buffer the pH value over a long time and therefore allow controlling the corrosion rate of zinc.

Effect of pulsed duty cycle control on tribological and corrosion properties of AISI-316 in cathodic cage plasma nitriding

NASA Astrophysics Data System (ADS)

Naeem, M.; Raza, H. A.; Shafiq, M.; Zaka-ul-Islam, M.; Iqbal, Javed; Díaz-Guillén, J. C.; Zakaullah, M.

2017-11-01

Austenitic stainless steels are of prime importance in many industrial sectors because of their excellent corrosion resistance; however, their poor mechanical and tribological features lead to their reduced applicability. In this regard, low-temperature cathodic cage plasma nitriding (CCPN) can be used to improve surface properties of steels without scarifying the inherent corrosion resistance. In this study, AISI-316 samples are processed in CCPN reactor at a temperature of 400 °C, for the treatment time of 4 h, at a pressure of 150 Pa and variable pulsed duty cycle (15-75%). The microstructure and mechanical features are analyzed using x-ray diffraction, scanning electron microscopy, microhardness tester and ball-on-disc wear tester. The anodic polarization test in 3.5% NaCl is conducted to examine the corrosion properties. The results show that hardness is enhanced up to 1327 HV at low duty cycle, which is considerably higher than base material (278 HV). The wear rate is found to be reduced up to 90% over base material by processing at low duty cycle. The base material exhibits severe abrasive wear, and the nitrided sample has dominant adhesive wear. The corrosion rate is found to be reduced up to 95% over base material for the sample nitrided at low duty cycle. This study shows that wear and corrosion resistance in CCPN can be significantly boosted by reducing the pulsed duty cycle.

Microencapsulation Technologies for Corrosion Protective Coating Applications

NASA Technical Reports Server (NTRS)

Li, Wenyan; Buhrow, Jerry; Jolley, Scott; Calle, Luz; Pearman, Benjamin; Zhang, Xuejun

2015-01-01

Microencapsulation technologies for functional smart Coatings for autonomous corrosion control have been a research area of strong emphasis during the last decade. This work concerns the development of pH sensitive micro-containers (microparticles and microcapsules) for autonomous corrosion control. This paper presents an overview of the state-of-the-art in the field of microencapsulation for corrosion control applications, as well as the technical details of the pH sensitive microcontainer approach, such as selection criteria for corrosion indicators and corrosion inhibitors; the development and optimization of encapsulation methods; function evaluation before and after incorporation of the microcontainers into coatings; and further optimization to improve coating compatibility and performance.

Corrosion resistance characteristics of a Ti-6Al-4V alloy scaffold that is fabricated by electron beam melting and selective laser melting for implantation in vivo.

PubMed

Zhao, Bingjing; Wang, Hong; Qiao, Ning; Wang, Chao; Hu, Min

2017-01-01

The purpose of this study is to determine the corrosion resistance of Ti-6Al-4V alloy fabricated with electron beam melting and selective laser melting for implantation in vivo. Ti-6Al-4V alloy specimens were fabricated with electron beam melting (EBM) and selective laser melting (SLM). A wrought form of Ti-6Al-4V alloy was used as a control. Surface morphology observation, component analysis, corrosion resistance experimental results, electrochemical impedance spectroscopy, crevice corrosion resistance experimental results, immersion test and metal ions precipitation analysis were processed, respectively. The thermal stability of EBM specimen was the worst, based on the result of open circuit potential (OCP) result. The result of electrochemical impedance spectroscopy indicated that the corrosion resistance of the SLM specimen was the best under the low electric potential. The result of potentiodynamic polarization suggested that the corrosion resistance of the SLM specimen was the best under the low electric potential (<1.5V) and EBM specimen was the best under the high electric potential (>1.5V).The crevice corrosion resistance of the EBM specimen was the best. The corrosion resistance of SLM specimen was the best, based on the result of immersion test. The content of Ti, Al and V ions of EBM, SLM and wrought specimens was very low. In general, the scaffolds that were fabricated with EBM and SLM had good corrosion resistance, and were suitable for implantation in vivo. Copyright © 2016 Elsevier B.V. All rights reserved.

NASA's Corrosion Technology Laboratory at the Kennedy Space Center: Anticipating, Managing, and Preventing Corrosion

NASA Technical Reports Server (NTRS)

Calle, Luz Marina

2015-01-01

The marine environment at NASAs Kennedy Space Center (KSC) has been documented by ASM International (formerly American Society for Metals) as the most corrosive in North America. With the introduction of the Space Shuttle in 1981, the already highly corrosive conditions at the launch pads were rendered even more severe by the highly corrosive hydrochloric acid (HCl) generated by the solid rocket boosters (SRBs). Numerous failures at the launch pads are caused by corrosion. The structural integrity of ground infrastructure and flight hardware is critical to the success, safety, cost, and sustainability of space missions. NASA has over fifty years of experience dealing with unexpected failures caused by corrosion and has developed expertise in corrosion control in the launch and other environments. The Corrosion Technology Laboratory at KSC evolved, from what started as an atmospheric exposure test site near NASAs launch pads, into a capability that provides technical innovations and engineering services in all areas of corrosion for NASA, external partners, and customers.This paper provides a chronological overview of NASAs role in anticipating, managing, and preventing corrosion in highly corrosive environments. One important challenge in managing and preventing corrosion involves the detrimental impact on humans and the environment of what have been very effective corrosion control strategies. This challenge has motivated the development of new corrosion control technologies that are more effective and environmentally friendly. Strategies for improved corrosion protection and durability can have a huge impact on the economic sustainability of human spaceflight operations.

Nano-engineering of superhydrophobic aluminum surfaces for anti-corrosion

NASA Astrophysics Data System (ADS)

Jeong, Chanyoung

Metal corrosion is a serious problem, both economically and operationally, for engineering systems such as aircraft, automobiles, pipelines, and naval vessels. In such engineering systems, aluminum is one of the primary materials of construction due to its light weight compared to steel and good general corrosion resistance. However, because of aluminum's relatively lower resistance to corrosion in salt water environments, protective measures such as thick coatings, paints, or cathodic protection must be used for satisfactory service life. Unfortunately, such anti-corrosion methods can create other concerns, such as environmental contamination, protection durability, and negative impact on hydrodynamic efficiency. Recently, a novel approach to preventing metal corrosion has emerged, using superhydrophobic surfaces. Superhydrophobic surfaces create a composite interface to liquid by retaining air within the surface structures, thus minimizing the direct contact of the liquid environment to the metal surface. The result is a highly non-wetting and anti-adherent surface that can offer other benefits such as biofouling resistance and hydrodynamic low friction. Prior research with superhydrophobic surfaces for corrosion applications was based on irregular surface roughening and/or chemical coatings, which resulted in random surface features, mostly on the micrometer scale. Such microscale surface roughness with poor controllability of structural dimensions and shapes has been a critical limitation to deeper understanding of the anti-corrosive effectiveness and optimized application of this approach. The research reported here provides a novel approach to producing controlled superhydrophobic nanostructures on aluminum that allows a systematic investigation of the superhydrophobic surface parameters on the corrosion resistance and hence can provide a route to optimization of the surface. Electrochemical anodization is used to controllably modulate the oxide layer thickness and pore dimensions at the aluminum surface. The results show that thicker oxide layers with larger pore sizes allow the nanostructured surface to retain more gas (air) and hence provide a more effective barrier to corrosion. The anodizing techniques are further advanced to design and produce hierarchical three-dimensional nanostructures for better retention of the gaseous barrier layer at the surface.

In vitro studying corrosion behavior of porous titanium coating in dynamic electrolyte.

PubMed

Chen, Xuedan; Fu, Qingshan; Jin, Yongzhong; Li, Mingtian; Yang, Ruisong; Cui, Xuejun; Gong, Min

2017-01-01

Porous titanium (PT) is considered as a promising biomaterials for orthopedic implants. Besides biocompatibility and mechanical properties, corrosion resistance in physiological environment is the other important factor affecting the long stability of an implant. In order to investigate the corrosion behavior of porous titanium implants in a dynamic physiological environment, a dynamic circle system was designed in this study. Then a titanium-based implant with PT coating was fabricated by plasma spraying. The corrosion resistance of PT samples in flowing 0.9% NaCl solution was evaluated by electrochemical measurements. Commercial pure solid titanium (ST) disc was used as a control. The studies of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) show that the pores in the PT play a negetive part in corrosion resistance and the flowing electrolyte can increase the corrosive rate of all titanium samples. The results suggest that pore design of titanium implants should pay attention to the effect of dynamic process of a physiological environment on the corrosion behavior of implants. Copyright © 2016 Elsevier B.V. All rights reserved.

Corrosion detector apparatus for universal assessment of pollution in data centers

DOEpatents

Hamann, Hendrik F.; Klein, Levente I.

2015-08-18

A compact corrosion measurement apparatus and system includes an air fan, a corrosion sensor, a temperature sensor, a humidity sensor, a heater element, and an air flow sensor all under control to monitor and maintain constant air parameters in an environment and minimize environmental fluctuations around the corrosion sensor to overcome the variation commonly encountered in corrosion rate measurement. The corrosion measurement apparatus includes a structure providing an enclosure within which are located the sensors. Constant air flow and temperature is maintained within the enclosure where the corrosion sensor is located by integrating a variable speed air fan and a heater with the corresponding feedback loop control. Temperature and air flow control loops ensure that corrosivity is measured under similar conditions in different facilities offering a general reference point that allow a one to one comparison between facilities with similar or different pollution levels.

Improvement of the linear polarization resistance method for testing steel corrosion inhibitors

NASA Astrophysics Data System (ADS)

Faritov, A. T.; Rozhdestvenskii, Yu. G.; Yamshchikova, S. A.; Minnikhanova, E. R.; Tyusenkov, A. S.

2016-11-01

The linear polarization resistance method is used to improve the technique of corrosion control in liquid conducting according to GOST 9.514-99 (General Corrosion and Aging Protection System. Corrosion Inhibitors for Metals in Water Systems. Electrochemical Method of Determining the Protective Ability). Corrosion monitoring is shown to be performed by electronic devices with real-time data transfer to industrial controllers and SCADA systems.

A New Maraging Stainless Steel with Excellent Strength–Toughness–Corrosion Synergy

PubMed Central

Tian, Jialong; Wang, Wei; Babar Shahzad, M.; Yan, Wei; Shan, Yiyin; Jiang, Zhouhua; Yang, Ke

2017-01-01

A new maraging stainless steel with superior strength–toughness–corrosion synergy has been developed based on an innovative concept of alloy design. The high strength–toughness combination is achieved by forming dispersive nano-sized intermetallic compounds in the soft lath martensitic matrix with a slight amount of residual austenite. The good corrosion resistance is guaranteed by exactly controlling the Co content based on understanding the synergistic effect between Co and Cr. The fine structure characteristics of two dominant strengthening precipitations including Ni3Ti and Mo-rich phases were finely characterized associated with transmission electron microscope (TEM) and atom probe tomography (APT) analyses. The relationship among microstructure, strength and toughness is discussed. The precipitation mechanism of different precipitates in the new maraging stainless steel is revealed based on the APT analysis. PMID:29125550

Ammonium salt corrosion in hydrotreating unit stripper column overhead systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shargay, C.A.; Jacobs, G.E.; Price, M.D.

In the past, the presence of ammonium bisulfide (NH{sub 4}HS) or ammonium chloride (NH{sub 4}Cl) in hydrotreater stripper overheads was relatively rare. However, designs of newer units and revamps to older units, are resulting in corrosive levels of NH{sub 4}HS or NH{sub 4}Cl in overhead systems. This is primarily due to the addition of a hot high pressure separator (HHPS) with the bottoms going directly (or through another separator) to the stripper. This paper presents data on one corrosion case history in detail, a summary of another case history reported in Retln-Cor 3.0 and the results of a brief surveymore » targeted to units with HHPS designs. Some correlations of the process conditions to the severity of corrosion are made based on the survey results, and recommended materials selection and other corrosion control methods to minimize the risk of this problem are given.« less

Characterization of newly synthesized pyrimidine derivatives for corrosion inhibition as inferred from computational chemical analysis

NASA Astrophysics Data System (ADS)

El-Taib Heakal, F.; Rizk, S. A.; Elkholy, A. E.

2018-01-01

Corrosion of metallic constructions is a serious problem in most industries worldwide that can be controlled via addition of special chemicals having adsorption capability on metal surfaces and hence isolating it from the aggressive environment. These chemicals are characterized by being rich in functional groups containing free lone pairs of electrons and/or π-electrons. In the present study four newly imidazole-pyrimidine based ionic derivatives have been synthesized and their structures were characterized by means of elemental analysis and different spectroscopic techniques. Quantum chemical calculations were carried out to give insights into the structural and electronic characteristics of these fabricated compounds. Monte Carlo simulation was also applied to shed the light on our prepared corrosion inhibitor molecules by examining their aptitude to adsorb on iron surface. Our ultimate goal is to help industries in fighting corrosion by providing them with a cheap and efficient anti-corrosion molecules.

Amplified OTDR systems for multipoint corrosion monitoring.

PubMed

Nascimento, Jehan F; Silva, Marcionilo J; Coêlho, Isnaldo J S; Cipriano, Eliel; Martins-Filho, Joaquim F

2012-01-01

We present two configurations of an amplified fiber-optic-based corrosion sensor using the optical time domain reflectometry (OTDR) technique as the interrogation method. The sensor system is multipoint, self-referenced, has no moving parts and can measure the corrosion rate several kilometers away from the OTDR equipment. The first OTDR monitoring system employs a remotely pumped in-line EDFA and it is used to evaluate the increase in system reach compared to a non-amplified configuration. The other amplified monitoring system uses an EDFA in booster configuration and we perform corrosion measurements and evaluations of system sensitivity to amplifier gain variations. Our experimental results obtained under controlled laboratory conditions show the advantages of the amplified system in terms of longer system reach with better spatial resolution, and also that the corrosion measurements obtained from our system are not sensitive to 3 dB gain variations.

Amplified OTDR Systems for Multipoint Corrosion Monitoring

PubMed Central

Nascimento, Jehan F.; Silva, Marcionilo J.; Coêlho, Isnaldo J. S.; Cipriano, Eliel; Martins-Filho, Joaquim F.

2012-01-01

We present two configurations of an amplified fiber-optic-based corrosion sensor using the optical time domain reflectometry (OTDR) technique as the interrogation method. The sensor system is multipoint, self-referenced, has no moving parts and can measure the corrosion rate several kilometers away from the OTDR equipment. The first OTDR monitoring system employs a remotely pumped in-line EDFA and it is used to evaluate the increase in system reach compared to a non-amplified configuration. The other amplified monitoring system uses an EDFA in booster configuration and we perform corrosion measurements and evaluations of system sensitivity to amplifier gain variations. Our experimental results obtained under controlled laboratory conditions show the advantages of the amplified system in terms of longer system reach with better spatial resolution, and also that the corrosion measurements obtained from our system are not sensitive to 3 dB gain variations. PMID:22737017

Modeling local chemistry in PWR steam generator crevices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Millett, P.J.

1997-02-01

Over the past two decades steam generator corrosion damage has been a major cost impact to PWR owners. Crevices and occluded regions create thermal-hydraulic conditions where aggressive impurities can become highly concentrated, promoting localized corrosion of the tubing and support structure materials. The type of corrosion varies depending on the local conditions, with stress corrosion cracking being the phenomenon of most current concern. A major goal of the EPRI research in this area has been to develop models of the concentration process and resulting crevice chemistry conditions. These models may then be used to predict crevice chemistry based on knowledgemore » of bulk chemistry, thereby allowing the operator to control corrosion damage. Rigorous deterministic models have not yet been developed; however, empirical approaches have shown promise and are reflected in current versions of the industry-developed secondary water chemistry guidelines.« less

49 CFR 195.583 - What must I do to monitor atmospheric corrosion control?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false What must I do to monitor atmospheric corrosion... monitor atmospheric corrosion control? (a) You must inspect each pipeline or portion of pipeline that is exposed to the atmosphere for evidence of atmospheric corrosion, as follows: If the pipeline islocated...

49 CFR 195.583 - What must I do to monitor atmospheric corrosion control?

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false What must I do to monitor atmospheric corrosion... monitor atmospheric corrosion control? (a) You must inspect each pipeline or portion of pipeline that is exposed to the atmosphere for evidence of atmospheric corrosion, as follows: If the pipeline islocated...

49 CFR 195.583 - What must I do to monitor atmospheric corrosion control?

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false What must I do to monitor atmospheric corrosion... monitor atmospheric corrosion control? (a) You must inspect each pipeline or portion of pipeline that is exposed to the atmosphere for evidence of atmospheric corrosion, as follows: If the pipeline islocated...

49 CFR 192.471 - External corrosion control: Test leads.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Test leads. 192.471... Control § 192.471 External corrosion control: Test leads. (a) Each test lead wire must be connected to the pipeline so as to remain mechanically secure and electrically conductive. (b) Each test lead wire must be...

49 CFR 192.471 - External corrosion control: Test leads.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Test leads. 192.471... Control § 192.471 External corrosion control: Test leads. (a) Each test lead wire must be connected to the pipeline so as to remain mechanically secure and electrically conductive. (b) Each test lead wire must be...

49 CFR 192.471 - External corrosion control: Test leads.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Test leads. 192.471... Control § 192.471 External corrosion control: Test leads. (a) Each test lead wire must be connected to the pipeline so as to remain mechanically secure and electrically conductive. (b) Each test lead wire must be...

49 CFR 192.453 - General.

Code of Federal Regulations, 2010 CFR

2010-10-01

... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.453 General. The corrosion control procedures required by § 192.605(b)(2), including those for the design... direction of, a person qualified in pipeline corrosion control methods. [Amdt. 192-71, 59 FR 6584, Feb. 11...

49 CFR 192.453 - General.

Code of Federal Regulations, 2011 CFR

2011-10-01

... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.453 General. The corrosion control procedures required by § 192.605(b)(2), including those for the design... direction of, a person qualified in pipeline corrosion control methods. [Amdt. 192-71, 59 FR 6584, Feb. 11...

49 CFR 192.453 - General.

Code of Federal Regulations, 2014 CFR

2014-10-01

... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.453 General. The corrosion control procedures required by § 192.605(b)(2), including those for the design... direction of, a person qualified in pipeline corrosion control methods. [Amdt. 192-71, 59 FR 6584, Feb. 11...

49 CFR 192.453 - General.

Code of Federal Regulations, 2013 CFR

2013-10-01

... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.453 General. The corrosion control procedures required by § 192.605(b)(2), including those for the design... direction of, a person qualified in pipeline corrosion control methods. [Amdt. 192-71, 59 FR 6584, Feb. 11...

49 CFR 192.453 - General.

Code of Federal Regulations, 2012 CFR

2012-10-01

... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.453 General. The corrosion control procedures required by § 192.605(b)(2), including those for the design... direction of, a person qualified in pipeline corrosion control methods. [Amdt. 192-71, 59 FR 6584, Feb. 11...

NASA's Corrosion Technology Laboratory at the Kennedy Space Center: Anticipating, Managing, and Preventing Corrosion

NASA Technical Reports Server (NTRS)

Calle, Luz Marina

2014-01-01

Corrosion is the degradation of a material that results from its interaction with the environment. The marine environment at NASAs Kennedy Space Center (KSC) has been documented by ASM International (formerly American Society for Metals) as the most corrosive in the United States. With the introduction of the Space Shuttle in 1981, the already highly corrosive conditions at the launch pads were rendered even more severe by the 70 tons of highly corrosive hydrochloric acid that were generated by the solid rocket boosters. Numerous failures at the launch pads are caused by corrosion.The structural integrity of ground infrastructure and flight hardware is critical to the success, safety, cost, and sustainability of space missions. As a result of fifty years of experience with launch and ground operations in a natural marine environment that is highly corrosive, NASAs Corrosion Technology Laboratory at KSC is a major source of corrosion control expertise in the launch and other environments. Throughout its history, the Laboratory has evolved from what started as an atmospheric exposure facility near NASAs launch pads into a world-wide recognized capability that provides technical innovations and engineering services in all areas of corrosion for NASA and external customers.This presentation will provide a historical overview of the role of NASAs Corrosion Technology in anticipating, managing, and preventing corrosion. One important challenge in managing and preventing corrosion involves the detrimental impact on humans and the environment of what have been very effective corrosion control strategies. This challenge has motivated the development of new corrosion control technologies that are more effective and environmentally friendly. Strategies for improved corrosion protection and durability can have a huge impact on the economic sustainability of human spaceflight operations.

Evaluation and control of environmental corrosion for aluminum and steel alloys

NASA Technical Reports Server (NTRS)

Franklin, D. B.

1977-01-01

Corrosion protection systems for aerospace application and the effects of surface treatments and methods of controlling stress corrosion are evaluated. Chromate pigmented systems were found to be most effective for aluminum alloys; zinc-rich coatings gave the greatest protection to steel alloys. Various steel and aluminum alloys are rated for stress corrosion resistance.

Powder Metallurgical Synthesis of Biodegradable Mg-Hydroxyapatite Composites for Biomedical Applications

NASA Astrophysics Data System (ADS)

Stüpp, Cesar Augusto; Szakács, Gábor; Mendis, Chamini Lakshi; Gensch, Felix; Müller, Sören; Feyerabend, Frank; Hotza, Dachamir; Fredel, Marcio Celso; Hort, Norbert

Magnesium alloys with acceptable or even controllable corrosion rates, where mechanical properties are not significantly modified or worsened, have been increasingly investigated in the last decade for use as biomaterials. This work shows an approach with a magnesium metal matrix composite (Mg-MMC), composed of ZK60 as base material and hydroxyapatite (HA) particles. The composite was produced by mechanical alloying followed by hot extrusion, as HA in contact with molten magnesium releases toxic gases such as phosphine (PH3). This work will present the influence of different amounts of HA on corrosion behaviour and mechanical properties of the investigated composites. Compared to the ZK60 alloy, corrosion is expected to be delayed, without localized corrosion. The mechanical properties are not expected to be compromised with such composite during tissue's healing period.

40 CFR 141.87 - Monitoring requirements for water quality parameters.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... (c) Monitoring after installation of corrosion control. Any large system which installs optimal corrosion control treatment pursuant to § 141.81(d)(4) shall measure the water quality parameters at the...)(i). Any small or medium-size system which installs optimal corrosion control treatment shall conduct...

40 CFR 141.87 - Monitoring requirements for water quality parameters.

Code of Federal Regulations, 2010 CFR

2010-07-01

.... (c) Monitoring after installation of corrosion control. Any large system which installs optimal corrosion control treatment pursuant to § 141.81(d)(4) shall measure the water quality parameters at the...)(i). Any small or medium-size system which installs optimal corrosion control treatment shall conduct...

40 CFR 141.87 - Monitoring requirements for water quality parameters.

Code of Federal Regulations, 2012 CFR

2012-07-01

.... (c) Monitoring after installation of corrosion control. Any large system which installs optimal corrosion control treatment pursuant to § 141.81(d)(4) shall measure the water quality parameters at the...)(i). Any small or medium-size system which installs optimal corrosion control treatment shall conduct...

40 CFR 141.87 - Monitoring requirements for water quality parameters.

Code of Federal Regulations, 2014 CFR

2014-07-01

.... (c) Monitoring after installation of corrosion control. Any large system which installs optimal corrosion control treatment pursuant to § 141.81(d)(4) shall measure the water quality parameters at the...)(i). Any small or medium-size system which installs optimal corrosion control treatment shall conduct...

40 CFR 141.87 - Monitoring requirements for water quality parameters.

Code of Federal Regulations, 2013 CFR

2013-07-01

.... (c) Monitoring after installation of corrosion control. Any large system which installs optimal corrosion control treatment pursuant to § 141.81(d)(4) shall measure the water quality parameters at the...)(i). Any small or medium-size system which installs optimal corrosion control treatment shall conduct...

Development of a Nonchromate Structural Adhesive Bond Primer

DTIC Science & Technology

2014-11-01

with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE NOV 2014 2. REPORT TYPE 3. DATES...Prevent corrosion of base metal • Applied to porous anodized surface • Overcoated with non-inhibited epoxy adhesive • High adhesive bond strength...primers •Long-running surveillance of chromate-free alternatives by UTC companies shows weak corrosion inhibition • (A) strontium chromate

A Multifunctional Coating for Autonomous Corrosion Control

NASA Technical Reports Server (NTRS)

Calle, L. M.; Hintze, P. E.; Li, W.; Buhrow, J. W.; Jolley, S. T.

2011-01-01

This slide presentation reviews the effects of corrosion on various structures at the Kennedy Space Center, and the work to discover a corrosion control coating that will be autonomous and will indicate corrosion at an early point in the process. Kennedy Space Center has many environmental conditions that are corrosive: ocean salt spray, heat, humidity, sunlight and acidic exhaust from the Solid Rocket Boosters (SRBs). Presented is a chart which shows the corrosion rates of carbon steel at various locations. KSC has the highest corrosion rates with 42.0 mils/yr, leading the next highest Galeta Point Beach, in the Panama Canal Zone with 27 mils/yr corrosion. A chart shows the changes in corrosion rate with the distance from the ocean. The three types of corrosion protective coatings are described: barrier (passive), Barrier plus active corrosion inhibiting components, and smart. A smart coating will detect and respond actively to changes in its environment in a functional and predictable manner and is capable of adapting its properties dynamically. The smart coating uses microcapsules, particles or liquid drops coated in polymers, that can detect and control the corrosion caused by the environment. The mechanism for a pH sensitive microcapsule and the hydrophobic core microcapsule are demonstrated and the chemistry is reviewed. When corrosion begins, the microcapsule will release the contents of the core (indicator, inhibitor, and self healing agent) in close proximity to the corrosion. The response to a pH increase is demonstrated by a series of pictures that show the breakdown of the microcapsule and the contents release. An example of bolt corrosion is used, as an example of corrosion in places that are difficult to ascertain. A comparison of various coating systems is shown.

A corrosion control manual for rail rapid transit

NASA Technical Reports Server (NTRS)

Gilbert, L. O.; Fitzgerald, J. F., II; Menke, J. T.

1982-01-01

In 1979, during the planning stage of the Metropolitan Dade County Transit System, the need was expressed for a corrosion control manual oriented to urban rapid transit system use. This manual responds to that need. The objective of the manual is to aid rail rapid transit agencies by providing practical solutions to selected corrosion problems. The scope of the manual encompasses corrosion problems of the facilities of rapid transit systems: structures and tracks, platforms and stations, power and signals, and cars. It also discusses stray electric current corrosion. Both design and maintenance solutions are provided for each problem. Also included are descriptions of the types of corrosion and their causes, descriptions of rapid transit properties, a list of corrosion control committees and NASA, DOD, and ASTM specifications and design criteria to which reference is made in the manual. A bibliography of papers and excerpts of reports and a glossary of frequency used terms are provided.

A glossary of corrosion-related terms used in science and industry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vukasovich, M.S.

1995-12-31

A Glossary of Corrosion-Related Terms Used in Science and Industry features definitions for over 4,000 specialized terms related to corrosion and corrosion prevention/control. Its coverage encompasses not only the fundamental terms commonly used in corrosion science, but also lesser-known, industry-specific jargon. The Glossary contains terms relevant to the study, effect, and control of corrosion that pertain to chemistry/electro-chemistry, metallurgy, plastics, paints/coatings, metal finishing, and the environment. Various synonyms, acronyms, and abbreviations are also included. A practical desk reference for students, scientists, engineers, technicians, and manufacturing and maintenance personnel.

Mechanical properties and bio-tribological behaviors of novel beta-Zr-type Zr-Al-Fe-Nb alloys for biomedical applications.

PubMed

Hua, Nengbin; Chen, Wenzhe; Zhang, Lei; Li, Guanghui; Liao, Zhenlong; Lin, Yan

2017-07-01

The present study prepares novel Zr 70+x Al 5 Fe 15-x Nb 10 (x=0, 5) alloys by arc-melting for potential biomedical application. The mechanical properties and bio-tribological behaviors of the Zr-based alloys are evaluated and compared with biomedical pure Zr. The as-prepared alloys exhibit a microstructure containing a micrometer-sized dendritic beta-Zr phase dispersed in a Zr 2 Fe-typed matrix. It is found that increasing the content of Zr is favorable for the mechanical compatibility with a combination of low Young's modulus, large plasticity, and high compressive strength. The wear resistance of the Zr-Al-Fe-Nb alloys in air and phosphate buffer saline (PBS) solution is superior to that of pure Zr. The wear mechanism of Zr-based alloys sliding in air is controlled by oxidation and abrasive wear whereas that sliding in PBS is controlled by synergistic effects of the abrasive and corrosive wear. Electrochemical measurements demonstrate that the Zr-based alloys are corrosion resistant in PBS. Their bio-corrosion resistance is improved with the increase in Zr content, which is attributed to the enrichment in Zr and decrease in Al concentration in the surface passive film of alloys. The Zr 75 Al 5 Fe 10 Nb 10 exhibits the best corrosion resistance in PBS, which contributes to its superior wear resistance in a simulated body environment. The combination of good mechanical properties, corrosion resistance, and biotribological behaviors of the Zr-Al-Fe-Nb alloys offers them potential advantages in biomedical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Study program for encapsulation materials interface for low cost silicon solar array

NASA Technical Reports Server (NTRS)

Kaelble, D. H.; Mansfeld, F. B.; Lunsden, J. B., III; Leung, C.

1980-01-01

An atmospheric corrosion model was developed and verified by five months of corrosion rate and climatology data acquired at the Mead, Nebraska LSA test site. Atmospheric corrosion rate monitors (ACM) show that moisture condensation probability and ionic conduction at the corroding surface or interface are controlling factors in corrosion rate. Protection of the corroding surface by encapsulant was shown by the ACM recordings to be maintained, independent of climatology, over the five months outdoor exposure period. The macroscopic corrosion processes which occur at Mead are shown to be reproduced in the climatology simulator. Controlled experiments with identical moisture and temperature aging cycles show that UV radiation causes corrosion while UV shielding inhibits LSA corrosion.

Characterization of biofilm and corrosion of cast iron pipes in drinking water distribution system with UV/Cl2 disinfection.

PubMed

Zhu, Ying; Wang, Haibo; Li, Xiaoxiao; Hu, Chun; Yang, Min; Qu, Jiuhui

2014-09-01

The effect of UV/Cl2 disinfection on the biofilm and corrosion of cast iron pipes in drinking water distribution system were studied using annular reactors (ARs). Passivation occurred more rapidly in the AR with UV/Cl2 than in the one with Cl2 alone, decreasing iron release for higher corrosivity of water. Based on functional gene, pyrosequencing assays and principal component analysis, UV disinfection not only reduced the required initial chlorine dose, but also enhanced denitrifying functional bacteria advantage in the biofilm of corrosion scales. The nitrate-reducing bacteria (NRB) Dechloromonas exhibited the greatest corrosion inhibition by inducing the redox cycling of iron to enhance the precipitation of iron oxides and formation of Fe3O4 in the AR with UV/Cl2, while the rhizobia Bradyrhizobium and Rhizobium, and the NRB Sphingomonas, Brucella producing siderophores had weaker corrosion-inhibition effect by capturing iron in the AR with Cl2. These results indicated that the microbial redox cycling of iron was possibly responsible for higher corrosion inhibition and lower effect of water Larson-Skold Index (LI) changes on corrosion. This finding could be applied toward the control of water quality in drinking water distribution systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Superhydrophobic powder additives to enhance chemical agent resistant coating systems for military equipment for the U.S. Marine Corps (USMC) Corrosion Prevention and Control (CPAC) Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pawel, Steven J.; Armstrong, Beth L.; Haynes, James A.

The primary goal of the CPAC program at ORNL was to explore the feasibility of introducing various silica-based superhydrophobic (SH) powder additives as a way to improve the corrosion resistance of US Department of Defense (DOD) military-grade chemical agent resistant coating (CARC) systems. ORNL had previously developed and patented several SH technologies of interest to the USMC, and one of the objectives of this program was to identify methods to incorporate these technologies into the USMC’s corrosion-resistance strategy. This report discusses findings of the CPAC and their application.

Natural analogues of nuclear waste glass corrosion.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abrajano, T.A. Jr.; Ebert, W.L.; Luo, J.S.

1999-01-06

This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serves as an analogue for the corrosion of high-level radioactive waste glasses in an engineered geologic disposal system. A wide range of natural and experimental corrosion studies has been performed on three major groups of natural glasses: tektite, obsidian, and basalt. Studies of the corrosion of natural glass attempt to characterize both the nature of alteration products and the reaction kinetics. Information availablemore » on natural glass was then compared to corresponding information on the corrosion of nuclear waste glasses, specifically to resolve two key questions: (1) whether one or more natural glasses behave similarly to nuclear waste glasses in laboratory tests, and (2) how these similarities can be used to support projections of the long-term corrosion of nuclear waste glasses. The corrosion behavior of basaltic glasses was most similar to that of nuclear waste glasses, but the corrosion of tektite and obsidian glasses involves certain processes that also occur during the corrosion of nuclear waste glasses. The reactions and processes that control basalt glass dissolution are similar to those that are important in nuclear waste glass dissolution. The key reaction of the overall corrosion mechanism is network hydrolysis, which eventually breaks down the glass network structure that remains after the initial ion-exchange and diffusion processes. This review also highlights some unresolved issues related to the application of an analogue approach to predicting long-term behavior of nuclear waste glass corrosion, such as discrepancies between experimental and field-based estimates of kinetic parameters for basaltic glasses.« less

Demystifying Controlling Copper Corrosion

EPA Science Inventory

The LCR systematically misses the highest health and corrosion risk sites for copper. Additionally, there are growing concerns for WWTP copper in sludges and discharge levels. There are many corrosion control differences between copper and lead. This talk explains the sometimes c...

Fretting and Corrosion at the Backside of Modular Cobalt Chromium Acetabular Inserts: A Retrieval Analysis.

PubMed

Tarity, T David; Koch, Chelsea N; Burket, Jayme C; Wright, Timothy M; Westrich, Geoffrey H

2017-03-01

Adverse local tissue reaction formation has been suggested to occur with the Modular Dual Mobility (MDM) acetabular design. Few reports in the literature have evaluated fretting and corrosion damage between the acetabular shell and modular metal inserts in this modular system. We evaluated a series of 18 retrieved cobalt chromium MDM inserts for evidence of fretting and corrosion. We assessed the backsides of 18 MDM components for evidence of fretting and corrosion in polar and taper regions based on previously established methods. We collected and assessed 30 similarly designed modular inserts retrieved from metal-on-metal (MoM) total hip arthroplasties as a control. No specific pattern of fretting or corrosion was identified on the MDM inserts. Both fretting and corrosion were significantly greater in the MoM cohort than the MDM cohort, driven by higher fretting and corrosion scores in the engaged taper region of the MoM inserts. MoM components demonstrated more fretting and corrosion than MDM designs, specifically at the taper region, likely driven by differences in the taper engagement mechanism and geometry among the insert designs. The lack of significant fretting and corrosion observed in the MDM inserts are inconsistent with recent claims that this interface may produce clinically significant metallosis and adverse local tissue reactions. Copyright © 2016 Elsevier Inc. All rights reserved.

78 FR 48845 - Hydrofluorosilicic Acid in Drinking Water; TSCA Section 21 Petition; Reasons for Agency Response

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-12

... the corrosivity of the water including: Taking further steps to optimize their corrosion control treatment (for water systems serving 50,000 people that have not fully optimized their corrosion control... Control Act (TSCA). The TSCA section 21 petition, dated May 9, 2013, was submitted by American University...

Minimization of corrosion using activated sodium bromide in a medium-size cooling tower

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nalepa, C.J.; Moore, R.M.; Golson, G.L.

1996-07-01

The cooling tower at the Albermarle Process Development Center in Baton Rouge, Louisiana, historically used chlorine as a biocide in combination with phosphorus-based corrosion/scale inhibitors. Although this regimen provided biocontrol, sludge and iron buildup was a problem in low-velocity, small cross-sectional areas of piping. A general cleanup of the system was performed in April 1995. This cleanup was followed with a switch to a two-component corrosion inhibitor/dispersant package. Alternate biocides were evaluated at this time. Activated sodium bromide was found to be particularly effective in this tower, which operates at pH {approximately}8.4. Relative to chlorine, the use of activated sodiummore » bromide led to a decrease in general and pitting corrosion on mild steel. The reduced corrosion appears to be due to a combination of both chemical (less attack on passivated metal surfaces) and biological factors (better control of heterotrophic and sessile bacteria). These conclusions are supported by chemical analyses, corrosion meter and coupon data, dip slides, biological activity reaction tests, and visual observations of the tower sump and heat exchanger surfaces.« less

Effect of Drag Reducing Polymer and Suspended Solid on the Rate of Diffusion Controlled Corrosion in 90° Copper Elbow

NASA Astrophysics Data System (ADS)

Fouad, Mohamed Ahmed; Zewail, Taghreed Mohamed; Amine, Nieven Kamal Abbes

2017-06-01

Rate of diffusion controlled corrosion in 90° Copper Elbow acidified dichromate has been investigated in relation to the following parameters: effect of solution velocity in the absence and presence of drag- reducing polymer on the rate of diffusion controlled corrosion, and effect of the presence of suspended solids on the rate of diffusion controlled corrosion. It was found that the presence of drag reducing polymer inhibited the rate of mass transfer, while the presence of suspended solid increased significantly the rate of mass transfer.

Corrosion Activities at the NASA Kennedy Space Center

NASA Technical Reports Server (NTRS)

Heidersbach, Robert H.

2002-01-01

This report documents summer faculty fellow efforts in the corrosion test bed at the NASA Kennedy Space Center. During the summer of 2002 efforts were concentrated on three activities: a short course on corrosion control for KSC personnel, evaluation of commercial wash additives used for corrosion control on Army aircraft, and improvements in the testing of a new cathodic protection system under development at KSC.

Corrosion Prevention and Control Planning Guidebook for Military Systems and Equipment

DTIC Science & Technology

2014-04-02

corrosion to applying advanced materials, coatings, inhibitors, and cathodic protection for corrosion control over many years, well before the DoD...requiring the delivery of the Contractor CPCP. Further, MIL-HDBK-1568 is for aerospace systems. Consider this when tailoring your Contract Data...Corrosion personnel from the user command; o Information Analysis Center personnel, such as Advanced Materials, Manufacturing, and Testing Information

Corrosion Control 101: A Journey in Rediscovery | Science ...

EPA Pesticide Factsheets

The presentation covers the general water chemistry of lead and copper, how contamination originates from home plumbing systems, what treatments are appropriate for controlling lead and copper to meet the Lead and Copper Rule, and what water quality and treatment factors directly impact the success and failure of corrosion control treatment. This talk re-introduces the overriding principles of corrosion control treatment to a water industry audience

Laboratory Evaluation of Expedient Low-Temperature Admixtures for Runway Craters in Cold Weather

DTIC Science & Technology

2014-10-01

ignores typical concerns, such as long-term durability, aesthetics, and corrosion , that are of minimal importance in this expedient field- use ...those identified to be in common use although it was acknowledged that the chloride based compounds caused corrosion problems (Korhonen 1990...batch to batch when using less than a 2000 lb batch, our ability to model and predict results with each batch is degraded. How- ever, when we control

Applications in the Nuclear Industry for Thermal Spray Amorphous Metal and Ceramic Coatings

NASA Astrophysics Data System (ADS)

Blink, J.; Farmer, J.; Choi, J.; Saw, C.

2009-06-01

Amorphous metal and ceramic thermal spray coatings have been developed with excellent corrosion resistance and neutron absorption. These coatings, with further development, could be cost-effective options to enhance the corrosion resistance of drip shields and waste packages, and limit nuclear criticality in canisters for the transportation, aging, and disposal of spent nuclear fuel. Iron-based amorphous metal formulations with chromium, molybdenum, and tungsten have shown the corrosion resistance believed to be necessary for such applications. Rare earth additions enable very low critical cooling rates to be achieved. The boron content of these materials and their stability at high neutron doses enable them to serve as high efficiency neutron absorbers for criticality control. Ceramic coatings may provide even greater corrosion resistance for waste package and drip shield applications, although the boron-containing amorphous metals are still favored for criticality control applications. These amorphous metal and ceramic materials have been produced as gas-atomized powders and applied as near full density, nonporous coatings with the high-velocity oxy-fuel process. This article summarizes the performance of these coatings as corrosion-resistant barriers and as neutron absorbers. This article also presents a simple cost model to quantify the economic benefits possible with these new materials.

Summary of the Sixth Persh Workshop: Corrosion Policy Guiding Science and Technology

DTIC Science & Technology

2016-01-01

mitigating corrosion. Corrosion affects military readiness, so corrosion prevention and control (CPC) have a high priority for the DOD since CPC is a...resulting in high -cost repairs. Corrosion mitigation is thus a key cost-effective approach for system maintainability and reduced life cycle costs. The... treatments . • Develop corrosion databases and corrosion models for predictive evaluation. Testing methods for realistic prediction of performance

Ground Truthing the 'Conventional Wisdom' of Lead Corrosion Control Using Mineralogical Analysis

EPA Science Inventory

For drinking water distribution systems (DWDS) with lead-bearing plumbing materials some form of corrosion control is typically necessary, with the goal of mitigating lead release by forming adherent, stable corrosion scales composed of low-solubility mineral phases. Conventional...

Effect of 1,2,4-triazole on galvanic corrosion between cobalt and copper in CMP based alkaline slurry

NASA Astrophysics Data System (ADS)

Fu, Lei; Liu, Yuling; Wang, Chenwei; Han, Linan

2018-04-01

Cobalt has become a new type of barrier material with its unique advantages since the copper-interconnects in the great-large scale integrated circuits (GLSI) into 10 nm and below technical nodes, but cobalt and copper have severe galvanic corrosion during chemical–mechanical flattening. The effect of 1,2,4-triazole on Co/Cu galvanic corrosion in alkaline slurry and the control of rate selectivity of copper and cobalt were investigated in this work. The results of electrochemical experiments and polishing experiments had indicated that a certain concentration of 1,2,4-triazole could form a layer of insoluble and dense passive film on the surface of cobalt and copper, which reduced the corrosion potential difference between cobalt and copper. Meantime, the removal rate of cobalt and copper could be effectively controlled according to demand during the CMP process. When the study optimized slurry was composed of 0.5 wt% colloidal silica, 0.1 %vol. hydrogen peroxide, 0.05 wt% FA/O, 345 ppm 1,2,4-triazole, cobalt had higher corrosion potential than copper and the galvanic corrosion could be reduced effectively when the corrosion potential difference between them decreased to 1 mV and the galvanic corrosion current density reached 0.02 nA/cm2. Meanwhile, the removal rate of Co was 62.396 nm/min, the removal rate of Cu was 47.328 nm/min, so that the removal rate ratio of cobalt and copper was 1.32 : 1, which was a good amendment to the dishing pits. The contact potential corrosion of Co/Cu was very weak, which could be better for meeting the requirements of the barrier CMP. Project supported by the Major National Science and Technology Special Projects (No. 2016ZX02301003-004-007), the Natural Science Foundation of Hebei Province, China (No. F2015202267), and the Outstanding Young Science and Technology Innovation Fund of Hebei University of Technology (No. 2015007).

Army Corrosion Prevention and Control (CPC) Program for Facilities and Infrastructure

DTIC Science & Technology

2010-02-01

FY2009 - 2011 • Benefits: Reduced corrosion due to elimination of metallic rebar , reduced weight equates to reduced dead load and increased dynamic...Decks as Replacement for Steel Reinforced Concrete Decks F09AR04: Corrosion Resistant Roofs with Integrated Sustainable PV Power Systems • Where...Army Corrosion Prevention and Control (CPC) Program for Facilities and Infrastructure Dr. Craig E. College Deputy Assistant Chief of Staff for

Management and control of microbiologically influenced corrosion (MIC) in the oil and gas industry-Overview and a North Sea case study.

PubMed

Skovhus, Torben Lund; Eckert, Richard B; Rodrigues, Edgar

2017-08-20

Microbiologically influenced corrosion (MIC) is the terminology applied where the actions of microorganisms influence the corrosion process. In literature, terms such as microbial corrosion, biocorrosion, microbially influenced/induced corrosion, and biodegradation are often applied. MIC research in the oil and gas industry has seen a revolution over the past decade, with the introduction of molecular microbiological methods: (MMM) as well as new industry standards and procedures of sampling biofilm and corrosion products from the process system. This review aims to capture the most important trends the oil and gas industry has seen regarding MIC research over the past decade. The paper starts out with an overview of where in the process stream MIC occurs - from the oil reservoir to the consumer. Both biotic and abiotic corrosion mechanisms are explained in the context of managing MIC using a structured corrosion management (CM) approach. The corrosion management approach employs the elements of a management system to ensure that essential corrosion control activities are carried out in an effective, sustainable, well-planned and properly executed manner. The 3-phase corrosion management approach covering of both biotic and abiotic internal corrosion mechanisms consists of 1) corrosion assessment, 2) corrosion mitigation and 3) corrosion monitoring. Each of the three phases are described in detail with links to recent field cases, methods, industry standards and sampling protocols. In order to manage the corrosion threat, operators commonly use models to support decision making. The models use qualitative, semi-quantitative or quantitative measures to help assess the rate of degradation caused by MIC. The paper reviews four existing models for MIC Threat Assessment and describe a new model that links the threat of MIC in the oil processing system located on an offshore platform with a Risk Based Inspection (RBI) approach. A recent field case highlights and explains the conflicting historic results obtained through serial dilution of culture media using the most probable number (MPN) method as compared to data obtained from corrosion monitoring and the quantitative polymerase chain reaction (qPCR) method. Results from qPCR application in the field case have changed the way MIC is monitored on the oil production facility in the North Sea. A number of high quality resources have been published as technical conference papers, books, educational videos and peer-reviewed scientific papers, and thus we end the review with an updated list of state-of-the-art resources for anyone desiring to become more familiar with the topic of MIC in the upstream oil and gas sector. Copyright © 2017 Elsevier B.V. All rights reserved.

Antifouling strategies and corrosion control in cooling circuits.

PubMed

Cristiani, P; Perboni, G

2014-06-01

Biofouling and corrosion phenomena dramatically reduce the functionality of industrial cooling circuits, especially in marine environments. This study underlines the effectiveness of a low level chlorination treatment of seawater to prevent biological fouling and biocorrosion. Reported examples emphasize the reaction of chlorine with bromide, ammonia and organic compounds in seawater and the effectiveness of a treatment performed in such a way to guarantee a residual concentration lower than 3μM at the outlet of the condensers. In a brief review of antifouling strategies, alternatives to chlorination and the monitoring approach able to optimize the treatments are also reported. An integrated, on-line system based on electrochemical probes (Biox system and a linear polarization resistance probe) demonstrated to be sufficient to monitor in real time: corrosion, biofilm growth and chemical treatments based on chlorine or alternative oxidant products (chlorine dioxide, etc.). A careful electrochemical monitoring and the optimized treatments help the plant operators of industrial cooling circuits prevent the decay of the equipment performance, allowing at the same time the control of the halogenated by-products formation. Copyright © 2014 Elsevier B.V. All rights reserved.

40 CFR 141.90 - Reporting requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... water system deemed to have optimized corrosion control under § 141.81(b)(3), a water system subject to...), and switching corrosion inhibitor products (e.g., orthophosphate to blended phosphate). Long-term... changed. (c) Corrosion control treatment reporting requirements. By the applicable dates under § 141.81...

40 CFR 141.90 - Reporting requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... water system deemed to have optimized corrosion control under § 141.81(b)(3), a water system subject to...), and switching corrosion inhibitor products (e.g., orthophosphate to blended phosphate). Long-term... changed. (c) Corrosion control treatment reporting requirements. By the applicable dates under § 141.81...

40 CFR 141.90 - Reporting requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... water system deemed to have optimized corrosion control under § 141.81(b)(3), a water system subject to...), and switching corrosion inhibitor products (e.g., orthophosphate to blended phosphate). Long-term... changed. (c) Corrosion control treatment reporting requirements. By the applicable dates under § 141.81...

40 CFR 141.90 - Reporting requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... water system deemed to have optimized corrosion control under § 141.81(b)(3), a water system subject to...), and switching corrosion inhibitor products (e.g., orthophosphate to blended phosphate). Long-term... changed. (c) Corrosion control treatment reporting requirements. By the applicable dates under § 141.81...

40 CFR 141.90 - Reporting requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... water system deemed to have optimized corrosion control under § 141.81(b)(3), a water system subject to...), and switching corrosion inhibitor products (e.g., orthophosphate to blended phosphate). Long-term... changed. (c) Corrosion control treatment reporting requirements. By the applicable dates under § 141.81...

Ground Truthing the ‘Conventional Wisdom’ of Lead Corrosion Control Using Mineralogical Analysis

EPA Science Inventory

For drinking water distribution systems (DWDS) with lead-bearing plumbing materials some form of corrosion control is typically necessary, with the goal of mitigating lead release by forming adherent, stable corrosion scales composed of low-solubility mineral phases. Conventional...

NEW INSIGHTS INTO LEAD CORROSION CONTROL AND TREATMENT CHANGE IMPACTS

EPA Science Inventory

This presentation will summarize recent research into the chemistry of lead corrosion control, and focus on five different areas that could impact the prediction of whether or not particular treatment changes are likely to either disturb existing lead corrosion scales, or to actu...

Controlling Surface Chemistry to Deconvolute Corrosion Benefits Derived from SMAT Processing

NASA Astrophysics Data System (ADS)

Murdoch, Heather A.; Labukas, Joseph P.; Roberts, Anthony J.; Darling, Kristopher A.

2017-07-01

Grain refinement through surface plastic deformation processes such as surface mechanical attrition treatment has shown measureable benefits for mechanical properties, but the impact on corrosion behavior has been inconsistent. Many factors obfuscate the particular corrosion mechanisms at work, including grain size, but also texture, processing contamination, and surface roughness. Many studies attempting to link corrosion and grain size have not been able to decouple these effects. Here we introduce a preprocessing step to mitigate the surface contamination effects that have been a concern in previous corrosion studies on plastically deformed surfaces; this allows comparison of corrosion behavior across grain sizes while controlling for texture and surface roughness. Potentiodynamic polarization in aqueous NaCl solution suggests that different corrosion mechanisms are responsible for samples prepared with the preprocessing step.

NEW INSIGHTS INTO LEAD AND COPPER CORROSION CONTROL AND TREATMENT CHANGE IMPACTS

EPA Science Inventory

This presentation summarizes recent research into the chemistry of lead corrosion control, and focus on different areas that could impact the prediction of whether or not particular treatment changes are likely to either disturb existing lead corrosion scales, or to actually impr...

Iron-Based Amorphous Metals: High-Performance Corrosion-Resistant Material Development

NASA Astrophysics Data System (ADS)

Farmer, Joseph; Choi, Jor-Shan; Saw, Cheng; Haslam, Jeffrey; Day, Dan; Hailey, Phillip; Lian, Tiangan; Rebak, Raul; Perepezko, John; Payer, Joe; Branagan, Daniel; Beardsley, Brad; D'Amato, Andy; Aprigliano, Lou

2009-06-01

An overview of the High-Performance Corrosion-Resistant Materials (HPCRM) Program, which was cosponsored by the Defense Advanced Research Projects Agency (DARPA) Defense Sciences Office (DSO) and the U.S. Department of Energy (DOE) Office of Civilian and Radioactive Waste Management (OCRWM), is discussed. Programmatic investigations have included a broad range of topics: alloy design and composition, materials synthesis, thermal stability, corrosion resistance, environmental cracking, mechanical properties, damage tolerance, radiation effects, and important potential applications. Amorphous alloys identified as SAM2X5 (Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4) and SAM1651 (Fe48Mo14Cr15Y2C15B6) have been produced as meltspun ribbons (MSRs), dropcast ingots, and thermal-spray coatings. Chromium (Cr), molybdenum (Mo), and tungsten (W) additions provided corrosion resistance, while boron (B) enabled glass formation. Earlier electrochemical studies of MSRs and ingots of these amorphous alloys demonstrated outstanding passive film stability. More recently, thermal-spray coatings of these amorphous alloys have been made and subjected to long-term salt-fog and immersion tests; good corrosion resistance has been observed during salt-fog testing. Corrosion rates were measured in situ with linear polarization, while the open-circuit corrosion potentials (OCPs) were simultaneously monitored; reasonably good performance was observed. The sensitivity of these measurements to electrolyte composition and temperature was determined. The high boron content of this particular amorphous metal makes this amorphous alloy an effective neutron absorber and suitable for criticality-control applications. In general, the corrosion resistance of such iron-based amorphous metals is maintained at operating temperatures up to the glass transition temperature. These materials are much harder than conventional stainless steel and Ni-based materials, and are proving to have excellent wear properties, sufficient to warrant their use in earth excavation, drilling, and tunnel-boring applications. Large areas have been successfully coated with these materials, with thicknesses of approximately 1 cm. The observed corrosion resistance may enable applications of importance in industries such as oil and gas production, refining, nuclear power generation, shipping, etc.

Emerging Nanotechnology-based Corrosion Control Coatings

DTIC Science & Technology

2009-02-01

Posdorfer, J., Synth. Met., 102, 1400-1401, 1999. • Fluoro- and silicon/silicone modified polymers • Organic- inorganic hybrid polymers Hopkins, A, The...O O S u b s t ra te Hybrid Organic- Inorganic Sol-gel Coating Bis-Ureasil HN NH O HN NH O Si MeO OMe MeO Si OMe OMe OMeR C2H5O Si OC2H5 OC2H5 OC2H5...Cycloaliphatic Amine 35% 65% 100% Nanotechnology-based coatings Ce+3Ce+3 Δ, H2O, OH - ΔEnviron > Tm =40 oC + Corrosion resistant Hybrid Organic- Inorganic

Corrosion engineering in the utilization of the Raft River geothermal resource

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, R.L.

1976-08-01

The economic impact of corrosion and the particular problems of corrosion in the utilization of geothermal energy resources are noted. Corrosion is defined and the parameters that control corrosion in geothermal systems are discussed. A general background of corrosion is presented in the context of the various forms of corrosion, in relation to the Raft River geothermal system. A basic reference for mechanical design engineers involved in the design of geothermal energy recovery systems is provided.

Inter-relationships between corrosion and mineral-scale deposition in aqueous systems.

PubMed

Hodgkiess, T

2004-01-01

The processes of corrosion and scale deposition in natural and process waters are often linked and this paper considers a number of instances of interactions between the two phenomena. In some circumstances a scale layer (e.g. calcium carbonate) can be advantageously utilised as a corrosion-protection coating on components and this feature has been exploited for many decades in the conditioning of water to induce spontaneous precipitation of a scale layer upon the surfaces of engineering equipment. The electrochemical mechanisms associated with some corrosion and corrosion-control processes can promote alkaline-scale deposition directly upon component surfaces. This is a feature that can be exploited in the operation of cathodic protection (CP) of structures and components submerged in certain types of water (e.g. seawater). Similar phenomena can occur during bi-metallic corrosion and a case study, involving carbon steel/stainless steel couples in seawater, is presented. Additional complexities pertain during cyclic loading of submerged reinforced concrete members in which scale deposition may reduce the severity of fatigue stresses but can be associated with severe corrosion damage to embedded reinforcing steel. Also considered are scale-control/corrosion interactions in thermal desalination plant and an indirect consequence of the scale-control strategy on vapourside corrosion is discussed.

Environmental factors affecting corrosion of munitions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bundy, K.; Bricka, M.; Morales, A.

1995-12-31

Spent small arms munitions have accumulated for years at outdoor firing ranges operated by the DoD and other groups. Used bullets are often subjected to moisture sources. There is increasing concern that accumulations of lead-based munitions represent potential sources of water and soil pollution. To understand both the severity of and solutions to this problem, it is necessary to measure how rapidly bullets corrode and to determine the soil variables affecting the process. In this study M16 bullets were buried in samples of soil taken from Louisiana army firing ranges. Four environmental conditions were simulated; rain water, acid rain, seamore » water, and 50% sea water/50% acid rain. The three electrode technique was used to measure the bullet corrosion. Graphite rods served as counter electrodes. A saturated calomel reference electrode was used along with a specially constructed salt bridge. Electrochemical measurements were conducted using a computer-controlled potentiostat to determine corrosion potential, soil resistance, and corrosion current. The rate of corrosion was found to markedly increase with decreasing soil pH and increasing chloride and moisture contents, with the chloride content being the most influential variable. High soil resistance and noble corrosion potential were found to be associated with low corrosion rates. This is important since both parameters can be readily measured in the field.« less

Selectable-Tip Corrosion-Testing Electrochemical Cell

NASA Technical Reports Server (NTRS)

Lomness, Janice; Hintze, Paul

2008-01-01

The figure depicts aspects of an electrochemical cell for pitting- corrosion tests of material specimens. The cell is designed to generate a region of corrosion having a pit diameter determined by the diameter of a selectable tip. The average depth of corrosion is controlled by controlling the total electric charge passing through the cell in a test. The cell is also designed to produce minimal artifacts associated with crevice corrosion. There are three selectable tips, having diameters of 0.1 in. (0.254 cm), 0.3 in. (0.762 cm), and 0.6 in. (1.524 cm), respectively.

High-Performance Polyimide Powder Coatings

NASA Technical Reports Server (NTRS)

2008-01-01

Much of the infrastructure at Kennedy Space Center and other NASA sites has been subjected to outside weathering effects for more than 40 years. Because much of this infrastructure has metallic surfaces, considerable effort is continually devoted to developing methods to minimize the effects of corrosion on these surfaces. These efforts are especially intense at KSC, where offshore salt spray and exhaust from Solid Rocket Boosters accelerate corrosion. Coatings of various types have traditionally been the choice for minimizing corrosion, and improved corrosion control methods are constantly being researched. Recent work at KSC on developing an improved method for repairing Kapton (polyimide)-based electrical wire insulation has identified polyimides with much lower melting points than traditional polyimides used for insulation. These lower melting points and the many other outstanding physical properties of polyimides (thermal stability, chemical resistance, and electrical properties) led us to investigate whether they could be used in powder coatings.

Effect of temperature on anodic behavior of 13Cr martensitic steel in CO2 environment

NASA Astrophysics Data System (ADS)

Zhao, G. X.; Zheng, M.; Lv, X. H.; Dong, X. H.; Li, H. L.

2005-04-01

The corrosion behavior of 13Cr martensitic stainless steel in a CO2 environment in a stimulated oilfield was studied with potentiodynamic polarization and the impedance spectra technique. The results showed that the microstructure of the surface scale clearly changed with temperature. This decreased the sensitivity of pitting corrosion and increased the tendency toward general (or uniform) corrosion. The capacitance, the charge transfer resistance, and the polarization resistance of the corrosion product scale decrease with increasing temperature from 90 to 120 °C, and thus the corrosion is a thermal activation controlled process. Charge transfer through the scale is difficult and the corrosion is controlled by a diffusion process at a temperature of 150 °C. Resistance charge transfer through the corrosion product layer is higher than that in the passive film.

Evaluating Rebar Corrosion Using Nonlinear Ultrasound

NASA Astrophysics Data System (ADS)

Woodward, Clinton; Amin, Md. Nurul

2008-02-01

The early detection of rebar corrosion in reinforced concrete is difficult using current methods. This pilot study investigated the viability of using nonlinear ultrasound to detect the effects of rebar corrosion in its early stages. The study utilized three accelerated corrosion specimens and one control specimen. Results showed that when corrosion developed in the area isonified by a Rayleigh wave, nonlinear parameters increased. As corrosion progressed, these nonlinear parameters also increased.

Effects of SO42- ions on the corrosion of GH3535 weld joint in FLiNaK molten salt

NASA Astrophysics Data System (ADS)

Zhu, Yasheng; Qiu, Jie; Hou, Juan; Liu, Wenguan; Chen, Huaican; Ai, Hua; Yu, Guojun; Wang, Jianqiang; Zhou, Xingtai

2017-08-01

The present work studied the impact of SO42- ions on the corrosion behaviors of GH3535 weld joint in FLiNaK molten salt. The concentration of SO42- ions in the FLiNaK molten salt was controlled by adjusting the quantity of Na2SO4 added into the salt. Results indicate that the SO42- ions in the FLiNaK salt speed up the corrosion rate remarkably by promoting the dissolution of Cr from the alloy matrix into the salt. With the concentration of SO42- ions in the FLiNaK salt increases from 100 ppm to 1000 ppm, the weight losses and the Cr depletion layer depths of the corroded specimens increase linearly. Even in the case of the heavy corrosion attack caused by the SO42- ions, the corrosion performance is similar between the base zone and fusion zone in the GH3535 weld joint. It is demonstrated that the structural diversity caused by the welding process has little impact on the corrosion performances of GH3535 alloy in FLiNaK molten salt.

Study for determination of industrial water corrosivity in Kashan Fajre Sepahan Galvanizing Mills during 2005-2006 Iran.

PubMed

Rabbani, D; Miranzadeh, M B; Motlagh, A Ahmadi

2008-01-01

This research was carried out in Kashan Fajre Sepahan Galvanizing mills (KFSGM) for evaluation of water corrosivity during 2005-2006. A total of 18 samples were taken from various points of the water supply system for testing the specific parameters and calculation Langelier Index (LI), Ryznar Index (RI) and Pukorious Index (PI). This research showed that in raw water (sand filter effluent) LI were positive as well as RI and PI were lower than 7 which means that mentioned water is not corrosive. Also LI in treated water by reverse osmosis process was negative and RI and PI were higher than 7, so, this water has corrosive properties. Finally, calculated indexes indicate that according to LI, conditioned water is not corrosive but based on RI and P. this water tend to corrosivity which this findings is compatible with literature review statement. So it is recommended that, for water conditioning addition of preservative chemicals to be continued but at the same time another alternatives such as pH adjustment, air stripping and deoxygenating, control of carbonate concentration and split flow treatment should be studied.

Peptide-based biocoatings for corrosion protection of stainless steel biomaterial in a chloride solution.

PubMed

Muruve, Noah G G; Cheng, Y Frank; Feng, Yuanchao; Liu, Tao; Muruve, Daniel A; Hassett, Daniel J; Irvin, Randall T

2016-11-01

In this work, PEGylated D-amino acid K122-4 peptide (D-K122-4-PEG), derived from the type IV pilin of Pseudomonas aeruginosa, coated on 304 stainless steel was investigated for its corrosion resistant properties in a sodium chloride solution by various electrochemical measurements, surface characterization and molecular dynamics simulation. As a comparison, stainless steel electrodes coated with non-PEGylated D-amino acid retroinverso peptide (RI-K122-4) and D-amino acid K122-4 peptide (D-K122-4) were used as control variables during electrochemical tests. It was found that the D-K122-4-PEG coating is able to protect the stainless steel from corrosion in the solution. The RI-K122-4 coating shows corrosion resistant property and should be investigated further, while the D-K122-4 peptide coating, in contrast, shows little to no effect on corrosion. The morphological characterizations support the corrosion resistance of D-K122-4-PEG on stainless steel. The adsorption of D-K122-4 molecules occurs preferentially on Fe2O3, rather than Cr2O3, present on the stainless steel surface. Copyright © 2016 Elsevier B.V. All rights reserved.

Controlling stress corrosion cracking in mechanism components of ground support equipment

NASA Technical Reports Server (NTRS)

Majid, W. A.

1988-01-01

The selection of materials for mechanism components used in ground support equipment so that failures resulting from stress corrosion cracking will be prevented is described. A general criteria to be used in designing for resistance to stress corrosion cracking is also provided. Stress corrosion can be defined as combined action of sustained tensile stress and corrosion to cause premature failure of materials. Various aluminum, steels, nickel, titanium and copper alloys, and tempers and corrosive environment are evaluated for stress corrosion cracking.

Research on a new type of fiber Bragg grating based corrosion sensor

NASA Astrophysics Data System (ADS)

Li, Peng; Song, Shide; Wang, Xiaona; Zhou, Weijie; Zhang, Zuocai

2015-08-01

Investigations of the corrosion of rebars in concrete structures are widely studied because of the serious damage to concrete caused by rebar corrosion. The rebar corrosion products in reinforced concrete take up 2~6 times the volume of the rebar. Based on this principle, a new type of fiber Bragg grating (FBG) corrosion sensor is proposed in this paper, which consists of two sensors, an FBG corrosion measurement sensor to measure the expansion strain caused by rebar corrosion, and a temperature compensation sensor to eliminate the cross-sensitivity of FBG corrosion sensor. The corrosion rate is derived by the wavelength shift of FBG corrosion sensor, so rebar corrosion can be monitored and assessed by the FBG wavelength shift. A customized rebar with epoxy fixing groove is designed to install a corrosion sensor on its surface and an embedded temperature compensation sensor. The corrosion sensor is embedded in cement mortar and subsequently casted in concrete. The performance of the corrosion sensor is studied in an accelerated electrochemical corrosion test. Experimental results show that the new type of corrosion sensor has advantage of relatively large measurement range of corrosion rate. The corrosion sensor is suitable to monitor slightly and moderately corroded rebars.

LabVIEW 2010 Computer Vision Platform Based Virtual Instrument and Its Application for Pitting Corrosion Study.

PubMed

Ramos, Rogelio; Zlatev, Roumen; Valdez, Benjamin; Stoytcheva, Margarita; Carrillo, Mónica; García, Juan-Francisco

2013-01-01

A virtual instrumentation (VI) system called VI localized corrosion image analyzer (LCIA) based on LabVIEW 2010 was developed allowing rapid automatic and subjective error-free determination of the pits number on large sized corroded specimens. The VI LCIA controls synchronously the digital microscope image taking and its analysis, finally resulting in a map file containing the coordinates of the detected probable pits containing zones on the investigated specimen. The pits area, traverse length, and density are also determined by the VI using binary large objects (blobs) analysis. The resulting map file can be used further by a scanning vibrating electrode technique (SVET) system for rapid (one pass) "true/false" SVET check of the probable zones only passing through the pit's centers avoiding thus the entire specimen scan. A complete SVET scan over the already proved "true" zones could determine the corrosion rate in any of the zones.

49 CFR 193.2625 - Corrosion protection.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Corrosion protection. 193.2625 Section 193.2625...: FEDERAL SAFETY STANDARDS Maintenance § 193.2625 Corrosion protection. (a) Each operator shall determine which metallic components could, unless corrosion is controlled, have their integrity or reliability...

49 CFR 193.2625 - Corrosion protection.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Corrosion protection. 193.2625 Section 193.2625...: FEDERAL SAFETY STANDARDS Maintenance § 193.2625 Corrosion protection. (a) Each operator shall determine which metallic components could, unless corrosion is controlled, have their integrity or reliability...

49 CFR 193.2625 - Corrosion protection.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Corrosion protection. 193.2625 Section 193.2625...: FEDERAL SAFETY STANDARDS Maintenance § 193.2625 Corrosion protection. (a) Each operator shall determine which metallic components could, unless corrosion is controlled, have their integrity or reliability...

49 CFR 193.2625 - Corrosion protection.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Corrosion protection. 193.2625 Section 193.2625...: FEDERAL SAFETY STANDARDS Maintenance § 193.2625 Corrosion protection. (a) Each operator shall determine which metallic components could, unless corrosion is controlled, have their integrity or reliability...

Corrosion inhibitors for water-base slurry in multiblade sawing

NASA Technical Reports Server (NTRS)

Chen, C. P.; Odonnell, T. P.

1982-01-01

The use of a water-base slurry instead of the standard PC oil vehicle was proposed for multiblade sawing (MBS) silicon wafering technology. Potential cost savings were considerable; however, significant failures of high-carbon steel blades were observed in limited tests using a water-based slurry during silicon wafering. Failures were attributed to stress corrosion. A specially designed fatigue test of 1095 steel blades in distilled water with various corrosion inhibitor solutions was used to determine the feasibility of using corrosion inhibitors in water-base MBS wafering. Fatigue tests indicate that several corrosion inhibitors have significant potential for use in a water-base MBS operation. Blade samples tested in these specific corrosion-inhibitor solutions exhibited considerably greater lifetime than those blades tested in PC oil.

Corrosion Prevention for Wheeled Vehicle Systems

DTIC Science & Technology

1993-08-13

The audit objective was to evaluate the effectiveness and efficiency of the Army’s procedures for acquiring corrosion prevention and chemical agent...resistant coatings for wheeled vehicle systems. To accomplish this objective, we reviewed corrosion controls and painting processes. The audit also...included a review of the adequacy of internal controls related to the audit objective.

Image-based corrosion recognition for ship steel structures

NASA Astrophysics Data System (ADS)

Ma, Yucong; Yang, Yang; Yao, Yuan; Li, Shengyuan; Zhao, Xuefeng

2018-03-01

Ship structures are subjected to corrosion inevitably in service. Existed image-based methods are influenced by the noises in images because they recognize corrosion by extracting features. In this paper, a novel method of image-based corrosion recognition for ship steel structures is proposed. The method utilizes convolutional neural networks (CNN) and will not be affected by noises in images. A CNN used to recognize corrosion was designed through fine-turning an existing CNN architecture and trained by datasets built using lots of images. Combining the trained CNN classifier with a sliding window technique, the corrosion zone in an image can be recognized.

The Corrosion Control of Fastening Systems for Aircraft Carrier Steam Catapults

DTIC Science & Technology

1976-03-31

mixture AT Aluminum powder and titanium powder 1:1 mixture MP Multiphase MP35N (powder) NA Nickel Aluminide base coat and aluminum top coat T Titanium ...Subsequent lifting or peeling was also accomplished by the use of a knife blade on areas not in contact with the "Fette Head". The densification process "s...75 of big bolt. White Titanium corrosion products elsewhere. After 552 hr. 57 salt spray AT .002 Aluminum/ Red rust in recess bottom around Titanium

US/Australia Collaborative Research Project on Corrosion Fatigue in D6AC Steel Joints

DTIC Science & Technology

1978-12-01

Life of Exposure Groups at 80,000 psi Max Load Level (R=0.1) 77 10 Location of Observable Fatigue Cracks on Failed D6AC Steel Specimen Surfaces 78 11...ing the machining and assembly process. Such liquids might have a serious deleterious effect on the fatigue life of the aircraft. Further, there was...control tests were to provide a base for determining the various corrosion effects on fatigue life , and to deter- mine any differences in laboratory

AGARD Corrosion Handbook. Volume 2. Aircraft Corrosion Control Documents: A Descriptive Catalogue

DTIC Science & Technology

1987-03-01

sweelb other than recommending that the use of maraging steel bolts be prohibited. However, it does provide a very good overview of the corrosion problems...as corrosion resistant steels in this manual. The metallurgy and general corrosion behavior of these steels is discussed in AGARD Corrosio.t Handbook...specifically with the selection of corrosion resistapt steels is a recommendation for prohibiting the use of maraging steel bolts in uncontrolled

49 CFR 195.588 - What standards apply to direct assessment?

Code of Federal Regulations, 2011 CFR

2011-10-01

... TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.588 What standards apply to direct... corrosion, you must follow the requirements of this section for performing external corrosion direct... direct assessment process. (b) The requirements for performing external corrosion direct assessment are...

49 CFR 195.588 - What standards apply to direct assessment?

Code of Federal Regulations, 2014 CFR

2014-10-01

... TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.588 What standards apply to direct... corrosion, you must follow the requirements of this section for performing external corrosion direct... direct assessment process. (b) The requirements for performing external corrosion direct assessment are...

49 CFR 195.588 - What standards apply to direct assessment?

Code of Federal Regulations, 2012 CFR

2012-10-01

... TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.588 What standards apply to direct... corrosion, you must follow the requirements of this section for performing external corrosion direct... direct assessment process. (b) The requirements for performing external corrosion direct assessment are...

49 CFR 195.588 - What standards apply to direct assessment?

Code of Federal Regulations, 2013 CFR

2013-10-01

... TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.588 What standards apply to direct... corrosion, you must follow the requirements of this section for performing external corrosion direct... direct assessment process. (b) The requirements for performing external corrosion direct assessment are...

78 FR 1726 - Airworthiness Directives; Burkhart GROB Luft- und Raumfahrt GmbH Sailplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-09

... purposes of this AD, we define slight corrosion as corrosion you can remove with metal wool and that has no visible pitting in the base metal. If you cannot remove the corrosion with metal wool or if there is visible pitting in the base metal, we define it as heavy corrosion. (3) If any cracks or heavy corrosion...

Investigation on localized corrosion of 304 stainless steel joints brazed using Sn-plated Ag alloy filler in NaCl aqueous solution

NASA Astrophysics Data System (ADS)

Wang, Xingxing; Li, Shuai; Peng, Jin

2018-03-01

Novel AgCuZnSn filler metal with high Sn contents was prepared from BAg50CuZn filler metal by a process of electroplating and thermal diffusion, and the prepared filler metal was applied to induction brazing of 304 stainless steel. The corrosion behavior of the brazed joints was evaluated based on localized corrosion analysis, the morphology of the joints were analyzed by SEM after immersion in a 3.5 vol% NaCl aqueous solution. The results indicated that corrosion groove occurred near the interface between the stainless steel base metal and the brazing seam. A wide range of defects such as holes and cracks appeared on the surface of the base metal, while the brazing seam zone almost no corrosion defects occur. With the increase of corrosion time, the corrosion rates of both the brazing seam and the base metal first exhibited an increasing trend, followed by a decreasing trend, and the corrosion rate of the base metal was slightly greater than that of the brazing seam. The corrosion potential of the brazing seam and 304 stainless steel were -0.7758 V and -0.7863 V, respectively.

Assessment of Microbiologically Influenced Corrosion Potential in the International Space Station Internal Active Thermal Control System Heat Exchanger Materials: A 6-Momths Study

NASA Technical Reports Server (NTRS)

Roman, Monsi C.; Macuch, Patrick; McKrell, Thomas; VanDerSchijff, Ockert J.; Mitchell, Ralph

2005-01-01

The fluid in the Internal Active Thermal Control System (IATCS) of the International Space Station (ISS) is water based. The fluid in the ISS Laboratory Module and Node 1 initially contained a mix of water, phosphate (corrosion control), borate (pH buffer), and silver sulfate (Ag2SO4) (microbial control) at a pH of 9.5+/-0.5. Over time, the chemistry of the fluid changed. Fluid changes included a pH drop from 9.5 to 8.3 due to diffusion of carbon dioxide (CO2) through Teflon(reistered Trademark) (DuPont) hoses, increases in dissolved nickel (Ni) levels, deposition of silver (Ag) to metal surfaces, and precipitation of the phosphate (PO4) as nickel phosphate (NiPO4). The drop in pH and unavailability of a antimicrobial has provided an environment conducive to microbial growth. Microbial levels in the fluid have increased from >10 colony-forming units (CFUs)/100 ml to 10(exp 6) CFUs/100 ml. The heat exchangers in the IATCS loops are considered the weakest point in the loop because of the material thickness (=7 mil). It is made of a Ni-based braze filler/CRES 347. Results of a preliminary test performed at Hamilton Sundstrand indicated the possibility of pitting on this material at locations where Ag deposits were found. Later, tests have confirmed that chemical corrosion of the materials is a concern for this system. Accumulation of micro-organisms on surfaces (biofilm) can also result in material degradation and can amplify the damage caused by the chemical corrosion, known as microbiologically influenced corrosion (MIC). This paper will discuss the results of a 6-mo test performed to characterize and quantify the damage from microbial accumulation on the surface of the ISS/ATCS heat exchanger materials. The test was designed to quantify the damage to the materials under worst-case conditions with and without micro-organisms present at pH 8.3 and 9.5.

Corrosion characteristics of nickel alloys. Citations from the International Aerospace Abstracts data base

NASA Technical Reports Server (NTRS)

Zollars, G. F.

1979-01-01

This bibliography cites 118 articles from the international literature concerning corrosion characteristics of nickel alloys. Articles dealing with corrosion resistance, corrosion tests, intergranular corrosion, oxidation resistance, and stress corrosion cracking of nickel alloys are included.

Biocorrosion behavior and cell viability of adhesive polymer coated magnesium based alloys for medical implants

NASA Astrophysics Data System (ADS)

Abdal-hay, Abdalla; Dewidar, Montasser; Lim, Jae Kyoo

2012-11-01

The present study was ultimately aimed to design novel adhesive biodegradable polymer, poly(vinyl acetate) (PVAc), coatings onto Mg based alloys by the dip-coating technique in order to control the degradation rate and enhance the biocompatibility of magnesium alloys. The influence of various solvents on PVAc surface topography and their protection of Mg alloys were dramatically studied in vitro. Electrochemical polarization, degradation, and PVAc film cytocompatibility were also tested. Our results showed that the solvent had a significant effect on coating quality. PVAc/dichloromethane solution showed a porous structure and solution concentration could control the porous size. The coatings prepared using tetrahydrofuran and dimethylformamide solvents are exceptional in their ability to generate porous morphology even at low polymer concentration. In general, the corrosion performance appears to be different on different PVAc-solvent system. Immersion tests illustrated that the porous morphology on PVAc stabilized corrosion rates. A uniform corrosion attack in artificial simulation body fluid was also exhibited. The cytocompatibility of osteoblast cells (MC3T3) revealed high adherence, proliferation, and survival on the porous structure of PVAc coated Mg alloy, which was not observed for the uncoated samples. This novel PVAc coating is a promising candidate for biodegradable implant materials, which might widen the use of Mg based implants.

Corrosion chemistry closing comments: opportunities in corrosion science facilitated by operando experimental characterization combined with multi-scale computational modelling.

PubMed

Scully, John R

2015-01-01

Recent advances in characterization tools, computational capabilities, and theories have created opportunities for advancement in understanding of solid-fluid interfaces at the nanoscale in corroding metallic systems. The Faraday Discussion on Corrosion Chemistry in 2015 highlighted some of the current needs, gaps and opportunities in corrosion science. Themes were organized into several hierarchical categories that provide an organizational framework for corrosion. Opportunities to develop fundamental physical and chemical data which will enable further progress in thermodynamic and kinetic modelling of corrosion were discussed. These will enable new and better understanding of unit processes that govern corrosion at the nanoscale. Additional topics discussed included scales, films and oxides, fluid-surface and molecular-surface interactions, selected topics in corrosion science and engineering as well as corrosion control. Corrosion science and engineering topics included complex alloy dissolution, local corrosion, and modelling of specific corrosion processes that are made up of collections of temporally and spatially varying unit processes such as oxidation, ion transport, and competitive adsorption. Corrosion control and mitigation topics covered some new insights on coatings and inhibitors. Further advances in operando or in situ experimental characterization strategies at the nanoscale combined with computational modelling will enhance progress in the field, especially if coupling across length and time scales can be achieved incorporating the various phenomena encountered in corrosion. Readers are encouraged to not only to use this ad hoc organizational scheme to guide their immersion into the current opportunities in corrosion chemistry, but also to find value in the information presented in their own ways.

49 CFR 192.479 - Atmospheric corrosion control: General.

Code of Federal Regulations, 2011 CFR

2011-10-01

... this section. (b) Coating material must be suitable for the prevention of atmospheric corrosion. (c... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion..., or experience appropriate to the environment of the pipeline that corrosion will— (1) Only be a light...

49 CFR 192.479 - Atmospheric corrosion control: General.

Code of Federal Regulations, 2010 CFR

2010-10-01

... this section. (b) Coating material must be suitable for the prevention of atmospheric corrosion. (c... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion..., or experience appropriate to the environment of the pipeline that corrosion will— (1) Only be a light...

Flow-induced corrosion behavior of absorbable magnesium-based stents.

PubMed

Wang, Juan; Giridharan, Venkataraman; Shanov, Vesselin; Xu, Zhigang; Collins, Boyce; White, Leon; Jang, Yongseok; Sankar, Jagannathan; Huang, Nan; Yun, Yeoheung

2014-12-01

The aim of this work was to study corrosion behavior of magnesium (Mg) alloys (MgZnCa plates and AZ31 stents) under varied fluid flow conditions representative of the vascular environment. Experiments revealed that fluid hydrodynamics, fluid flow velocity and shear stress play essential roles in the corrosion behavior of absorbable magnesium-based stent devices. Flow-induced shear stress (FISS) accelerates the overall corrosion (including localized, uniform, pitting and erosion corrosions) due to the increased mass transfer and mechanical force. FISS increased the average uniform corrosion rate, the localized corrosion coverage ratios and depths and the removal rate of corrosion products inside the corrosion pits. For MgZnCa plates, an increase of FISS results in an increased pitting factor but saturates at an FISS of ∼0.15Pa. For AZ31 stents, the volume loss ratio (31%) at 0.056Pa was nearly twice that (17%) at 0Pa before and after corrosion. Flow direction has a significant impact on corrosion behavior as more severe pitting and erosion corrosion was observed on the back ends of the MgZnCa plates, and the corrosion product layer facing the flow direction peeled off from the AZ31 stent struts. This study demonstrates that flow-induced corrosion needs be understood so that Mg-based stents in vascular environments can be effectively designed. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Effects of grain size on the corrosion resistance of pure magnesium by cooling rate-controlled solidification

NASA Astrophysics Data System (ADS)

Liu, Yichi; Liu, Debao; You, Chen; Chen, Minfang

2015-09-01

The aim of this study was to investigate the effect of grain size on the corrosion resistance of pure magnesium developed for biomedical applications. High-purity magnesium samples with different grain size were prepared by the cooling rate-controlled solidification. Electrochemical and immersion tests were employed to measure the corrosion resistance of pure magnesium with different grain size. The electrochemical polarization curves indicated that the corrosion susceptibility increased as the grain size decrease. However, the electrochemical impedance spectroscopy (EIS) and immersion tests indicated that the corrosion resistance of pure magnesium is improved as the grain size decreases. The improvement in the corrosion resistance is attributed to refine grain can produce more uniform and density film on the surface of sample.

Corrosion control and disinfection studies in spacecraft water systems. [considering Saturn 5 orbital workshop

NASA Technical Reports Server (NTRS)

Shea, T. G.

1974-01-01

Disinfection and corrosion control in the water systems of the Saturn 5 Orbital Workshop Program are considered. Within this framework, the problem areas of concern are classified into four general areas: disinfection; corrosion; membrane-associated problems of disinfectant uptake and diffusion; and taste and odor problems arising from membrane-disinfectant interaction.

Corrosion control of carbon steel using inhibitor of banana peel extract in acid diluted solutions

NASA Astrophysics Data System (ADS)

Komalasari; Utami, S. P.; Fermi, M. I.; Aziz, Y.; Irianti, R. S.

2018-04-01

Issues of corrosion happened in pipes, it was used as fluid transportation in the chemical industry. Corrosion cannot be preventing, however it could be controlled or blocked. Inhibitor addition is one of the method to control the corrosion inside the pipe. Corrosion inhibitors consisted of inorganic and organic compound inhibitors. Organic inhibitor is composed from synthetic and natural material. This study focused to evaluate the inhibition’s efficiency from banana peel to carbon steel in different concentration of inhibitor and immersing time in acid solution variation. The research employed inhibitor concentration of 0 gram/liter, 2 gram/liter, 4 gram/liter and 6 gram/liter, immersed time of carbon steel for 2, 4, 6, 8 and 10 hours. It was immersed in chloride acid solution of 0.5 M and 1.5 M. Carbon Steel AISI 4041 was used as specimen steel. Results were analyzed using corrosion rate evaluation for each specimens and inhibitor efficiencies determination. It was found that the specimen without inhibitor yielded fast corrosion rate in long immersing time and high concentration of HCl. However, the specimens with inhibitor gave lowest corrosion rate which was 78.59% for 6 gram/litre and 10 hours in 0.5 M HCl.

Corrosion and Corrosion Control in Light Water Reactors

NASA Astrophysics Data System (ADS)

Gordon, Barry M.

2013-08-01

Serious corrosion problems have plagued the light water reactor (LWR) industry for decades. The complex corrosion mechanisms involved and the development of practical engineering solutions for their mitigation will be discussed in this article. After a brief overview of the basic designs of the boiling water reactor (BWR) and pressurized water reactor (PWR), emphasis will be placed on the general corrosion of LWR containments, flow-accelerated corrosion of carbon steel components, intergranular stress corrosion cracking (IGSCC) in BWRs, primary water stress corrosion cracking (PWSCC) in PWRs, and irradiation-assisted stress corrosion cracking (IASCC) in both systems. Finally, the corrosion future of both plants will be discussed as plants extend their period of operation for an additional 20 to 40 years.

Corrosion of aluminium in soft drinks.

PubMed

Seruga, M; Hasenay, D

1996-04-01

The corrosion of aluminium (Al) in several brands of soft drinks (cola- and citrate-based drinks) has been studied, using an electrochemical method, namely potentiodynamic polarization. The results show that the corrosion of Al in soft drinks is a very slow, time-dependent and complex process, strongly influenced by the passivation, complexation and adsorption processes. The corrosion of Al in these drinks occurs principally due to the presence of acids: citric acid in citrate-based drinks and orthophosphoric acid in cola-based drinks. The corrosion rate of Al rose with an increase in the acidity of soft drinks, i.e. with increase of the content of total acids. The corrosion rates are much higher in the cola-based drinks than those in citrate-based drinks, due to the facts that: (1) orthophosphoric acid is more corrosive to Al than is citric acid, (2) a quite different passive oxide layer (with different properties) is formed on Al, depending on whether the drink is cola or citrate based. The method of potentiodynamic polarization was shown as being very suitable for the study of corrosion of Al in soft drinks, especially if it is combined with some non-electrochemical method, e.g. graphite furnace atomic absorption spectrometry (GFAAS).

Characteristics of lead corrosion scales formed during drinking water distribution and their potential influence on the release of lead and other contaminants.

PubMed

Kim, Eun Jung; Herrera, Jose E

2010-08-15

Destabilization of the corrosion scale present in lead pipes used in drinking water distribution systems is currently considered a major problem for municipalities serviced in part by lead pipes. Although several lead corrosion strategies have been deployed with success, a clear understanding of the chemistry of corrosion products present in the scale is needed for an effective lead control. This contribution focuses on a comprehensive characterization of the layers present in the corrosion scale formed on the inner surfaces of lead pipes used in the drinking water distribution system of the City on London, ON, Canada. Solid corrosion products were characterized using X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Toxic elements accumulated in the corrosion scale were also identified using inductively coupled plasma (ICP) spectrometry after acid digestion. Based on the XRD results, hydrocerussite was identified as the major lead crystalline corrosion phase in most of the pipes sampled, while cerussite was observed as the main crystalline component only in a few cases. Lead oxides including PbO(2) and Pb(3)O(4) were also observed in the inner layers of the corrosion scale. The presence of these highly oxidized lead species is rationalized in terms of the lead(II) carbonate phase transforming into lead(IV) oxide through an intermediate Pb(3)O(4) (2Pb(II)O x Pb(IV)O(2)) phase. In addition to lead corrosion products, an amorphous aluminosilicate phase was also identified in the corrosion scale. Its concentration is particularly high at the outer surface layers. Accumulation of toxic contaminants such as As, V, Sb, Cu, and Cr was observed in the corrosion scales, together with a strong correlation between arsenic accumulation and aluminum concentration.

49 CFR 192.490 - Direct assessment.

Code of Federal Regulations, 2011 CFR

2011-10-01

... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.490 Direct.... Threat Standard 1 External corrosion § 192.925 2 Internal corrosion in pipelines that transport dry gas § 192.927 Stress corrosion cracking § 192.929 1 For lines not subject to subpart O of this part, the...

49 CFR 192.490 - Direct assessment.

Code of Federal Regulations, 2014 CFR

2014-10-01

... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.490 Direct.... Threat Standard 1 External corrosion § 192.925 2 Internal corrosion in pipelines that transport dry gas § 192.927 Stress corrosion cracking § 192.929 1 For lines not subject to subpart O of this part, the...

49 CFR 192.490 - Direct assessment.

Code of Federal Regulations, 2013 CFR

2013-10-01

... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.490 Direct.... Threat Standard 1 External corrosion § 192.925 2 Internal corrosion in pipelines that transport dry gas § 192.927 Stress corrosion cracking § 192.929 1 For lines not subject to subpart O of this part, the...

49 CFR 192.490 - Direct assessment.

Code of Federal Regulations, 2012 CFR

2012-10-01

... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.490 Direct.... Threat Standard 1 External corrosion § 192.925 2 Internal corrosion in pipelines that transport dry gas § 192.927 Stress corrosion cracking § 192.929 1 For lines not subject to subpart O of this part, the...

49 CFR 192.490 - Direct assessment.

Code of Federal Regulations, 2010 CFR

2010-10-01

... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.490 Direct.... Threat Standard 1 External corrosion § 192.925 2 Internal corrosion in pipelines that transport dry gas § 192.927 Stress corrosion cracking § 192.929 1 For lines not subject to subpart O of this part, the...

Corrosion due to use of carbon dioxide for enhanced oil recovery. Final report. SumX No. 78-003

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeBerry, D.W.; Clark, W.S.

1979-09-01

This study documents the specific effects of CO/sub 2/ on corrosion and identifies promising methods for controlling corrosion in fields using CO/sub 2/ injection. Information has been assembled on: CO/sub 2/ corrosion problems in general, surface and downhole corrosion problems specifically associated with CO/sub 2/ enhanced oil recovery, and methods to reduce corrosion problems in CO/sub 2/ environments. Corrosion mechanisms, kinetic behavior, and the effects of various parameters on corrosion by CO/sub 2/ are presented in this study. Engineering metals are not attacked by CO/sub 2/ under oil field environments unless liquid water is also present. Plain and low alloymore » steels are attacked by mixtures of CO/sub 2/ and liquid water. Attack on these bare metals may become serious at a CO/sub 2/ partial pressure as low as 4 psi and it increases with CO/sub 2/ partial pressure although not in direct proportion. Fluid flow rate is an important factor in CO/sub 2//water corrosion. Practically all stainless steels and similar resistant alloys are not particularly subject to corrosion by CO/sub 2//water mixtures alone, even at high CO/sub 2/ pressures. Elevated levels of CO/sub 2/ can aggravate the corrosive effects of other species such as hydrogen sulfide, oxygen, and chloride. Mixtures of CO/sub 2/, carbon monoxide (CO), and water can cause stress corrosion cracking of plain steels. Corrosion problems in CO/sub 2/ systems should be circumvented when possible by avoiding combination of the corrosive components. Although water cannot be excluded throughout the CO/sub 2/ injection-oil production-CO/sub 2/ and water reinjection chain, air in-leakage can be minimized and oxygen scavengers used to remove any residual. Exclusion of oxygen is important to the successful use of other corrosion control measures. A discussion is given of the main control methods including metal selection, protective coatings and nonmetallic materials, and chemical inhibition. (DLC)« less

Corrosion Performance of Fe-Based Alloys in Simulated Oxy-Fuel Environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zeng, Zuotao; Natesan, Ken; Cai, Zhonghou

The long-term corrosion of Fe-based alloys in simulated oxy-fuel environment at 1023 K (750 A degrees C) was studied. Detailed results are presented on weight change, scale thickness, internal penetration, microstructural characteristics of the corrosion products, and the cracking of scales for the alloys after exposure at 1023 K (750 A degrees C) for up to 3600 hours. An incubation period during which the corrosion rate was low was observed for the alloys. After the incubation period, the corrosion accelerated, and the corrosion process followed linear kinetics. Effects of alloy, CaO-containing ash, and gas composition on the corrosion rate weremore » also studied. In addition, synchrotron nanobeam X-ray analysis was employed to determine the phase and chemical composition of the oxide layers on the alloy surface. Results from these studies are being used to address the long-term corrosion performance of Fe-based alloys in various coal-ash combustion environments and to develop methods to mitigate high-temperature ash corrosion.« less

Hot corrosion of four superalloys - HA-188, S-57, IN-617, and TD-NiCrAl

NASA Technical Reports Server (NTRS)

Santoro, G. J.

1979-01-01

Cyclic oxidation and hot corrosion tests of two cobalt-base and two nickel-base alloys are reported. The alloys were exposed to maximum temperatures of 900 and 1000 C in a Mach 0.3 burner rig whose flame was doped with various concentrations of sea salt and sodium sulfate for hot corrosion tests. The test data were subjected to a regression analysis for the development of model equations relating corrosion to temperature and for the effects of salt concentration and composition on corrosion. The corrosion resistance varied with temperature, sea salt concentration, and salt composition, concluding that the S-57 cobalt-base alloy was the most hot corrosion-resistant alloy, and the TD-NiCrAl nickel-base alloy was the least resistant. However, under straight oxidation conditions, the TD-NiCrAl was most resistant, while S-57 was the least resistant alloy.

Corrosion of Tungsten Microelectrodes used in Neural Recording Applications

PubMed Central

Patrick, Erin; Orazem, Mark E.; Sanchez, Justin C.; Nishida, Toshikazu

2011-01-01

In neuroprosthetic applications, long-term electrode viability is necessary for robust recording of the activity of neural populations used for generating communication and control signals. The corrosion of tungsten microwire electrodes used for intracortical recording applications was analyzed in a controlled bench-top study and compared to the corrosion of tungsten microwires used in an in vivo study. Two electrolytes were investigated for the benchtop electrochemical analysis: 0.9% phosphate buffered saline (PBS) and 0.9% PBS containing 30 mM of hydrogen peroxide. The oxidation and reduction reactions responsible for corrosion were found by measurement of the open circuit potential and analysis of Pourbaix diagrams. Dissolution of tungsten to form the tungstic ion was found to be the corrosion mechanism. The corrosion rate was estimated from the polarization resistance, which was extrapolated from the electrochemical impedance spectroscopy data. The results show that tungsten microwires in an electrolyte of PBS have a corrosion rate of 300–700 µm/yr. The corrosion rate for tungsten microwires in an electrolyte containing PBS and 30 mM H2O2 is accelerated to 10,000–20,000 µm/yr. The corrosion rate was found to be controlled by the concentration of the reacting species in the cathodic reaction (e.g. O2 and H2O2). The in vivo corrosion rate, averaged over the duration of implantation, was estimated to be 100 µm/yr. The reduced in vivo corrosion rate as compared to the benchtop rate is attributed to decreased rate of oxygen diffusion caused by the presence of a biological film and a reduced concentration of available oxygen in the brain. PMID:21470563

Corrosion of tungsten microelectrodes used in neural recording applications.

PubMed

Patrick, Erin; Orazem, Mark E; Sanchez, Justin C; Nishida, Toshikazu

2011-06-15

In neuroprosthetic applications, long-term electrode viability is necessary for robust recording of the activity of neural populations used for generating communication and control signals. The corrosion of tungsten microwire electrodes used for intracortical recording applications was analyzed in a controlled bench-top study and compared to the corrosion of tungsten microwires used in an in vivo study. Two electrolytes were investigated for the bench-top electrochemical analysis: 0.9% phosphate buffered saline (PBS) and 0.9% PBS containing 30 mM of hydrogen peroxide. The oxidation and reduction reactions responsible for corrosion were found by measurement of the open circuit potential and analysis of Pourbaix diagrams. Dissolution of tungsten to form the tungstic ion was found to be the corrosion mechanism. The corrosion rate was estimated from the polarization resistance, which was extrapolated from the electrochemical impedance spectroscopy data. The results show that tungsten microwires in an electrolyte of PBS have a corrosion rate of 300-700 μm/yr. The corrosion rate for tungsten microwires in an electrolyte containing PBS and 30 mM H₂O₂ is accelerated to 10,000-20,000 μm/yr. The corrosion rate was found to be controlled by the concentration of the reacting species in the cathodic reaction (e.g. O₂ and H₂O₂). The in vivo corrosion rate, averaged over the duration of implantation, was estimated to be 100 μm/yr. The reduced in vivo corrosion rate as compared to the bench-top rate is attributed to decreased rate of oxygen diffusion caused by the presence of a biological film and a reduced concentration of available oxygen in the brain. Copyright © 2011 Elsevier B.V. All rights reserved.

Recent progress to understand stress corrosion cracking in sodium borosilicate glasses: linking the chemical composition to structural, physical and fracture properties

NASA Astrophysics Data System (ADS)

Rountree, Cindy L.

2017-08-01

This topical review is dedicated to understanding stress corrosion cracking in oxide glasses and specifically the SiO_2{\\text-B_2O_3{\\text-}Na_2O} (SBN) ternary glass systems. Many review papers already exist on the topic of stress corrosion cracking in complex oxide glasses or overly simplified glasses (pure silica). These papers look at how systematically controlling environmental factors (pH, temperature...) alter stress corrosion cracking, while maintaining the same type of glass sample. Many questions still exist, including: What sets the environmental limit? What sets the velocity versus stress intensity factor in the slow stress corrosion regime (Region I)? Can researchers optimize these two effects to enhance a glass’ resistance to failure? To help answer these questions, this review takes a different approach. It looks at how systemically controlling the glass’ chemical composition alters the structure and physical properties. These changes are then compared and contrasted to the fracture toughness and the stress corrosion cracking properties. By taking this holistic approach, researchers can begin to understand the controlling factors in stress corrosion cracking and how to optimize glasses via the initial chemical composition.

[The Research on Optic Fiber FBG Corrosion Sensor Based on the Analysis of the Spectral Characteristics].

PubMed

Zhang, Jun; Zeng, Jie; Wang, Bo; Wang, Wen-juan; Liang, Da-kai; Liu, Xiao-ying

2016-03-01

Aiming at meeting the need of aluminum corrosion monitoring in aerospace field, a pre-load type fiber grating corrosion sensor based on an aluminum thin tube structure is proposed. The corrosion sensor of aluminum alloy structure in-service monitoring mechanism is studied, a theoretical model about the relation of FBG reflection spectral characteristics and aluminum thickness variation is also obtained. Optical fiber grating corrosion monitoring test system based on the capillary structure of aluminum alloy is constructed by acid-base environment. The problem of cross sensitivity of temperature and strain is solved by configuring an optical fiber grating which is not affected by strain and only sensitive to temperature inside the aluminum alloy tube. The results shows that he aluminum tube packaging design not only can sense the effects of corrosion on the mechanical properties, but also can interference shielding effect of corrosion on the tube optical fiber sensing device. With the deepening of the metal tube corrosion and aluminum alloy tube thickness gradually thinning, fiber grating reflective spectrum gradually shift to the short wavelength and the wall thickness and the grating center wavelength offset has a good monotonic relation. These characteristics can provide useful help to further research corrosion online monitoring based on optic fiber sensor.

Preventing Corrosion by Controlling Cathodic Reaction Kinetics

DTIC Science & Technology

2016-03-25

electrochemical reaction rates of processes that drive corrosion, e.g. the oxygen reduction reaction (ORR). To this end, we have used reactive...elements on the kinetics of oxygen reduction reaction catalyzed on titanium oxide in order to develop new approaches for controlling galvanic corrosion... consumption of anions in reactions with metal cations can deplete the electrolyte. However, in the atmospheric electrolyte, the electrolyte

Anode film formation and control

DOEpatents

Koski, Oscar; Marschman, Steven C.

1990-01-01

A protective film is created about the anode within a cryolite-based electrolyte during electrolytic production of aluminum from alumina. The film function to minimize corrosion of the anode by the cryolitic electrolyte and thereby extend the life of the anode. Various operating parameters of the electrolytic process are controlled to maintain the protective film about the anode in a protective state throughout the electrolytic reduction of alumina. Such parameters include electrolyte temperature, electrolyte ratio, current density, and Al.sub.2 O.sub.3 concentration. An apparatus is also disclosed to enable identification of the onset of anode corrosion due to disruption of the film to provide real time information regarding the state of the film.

Anode film formation and control

DOEpatents

Koski, O.; Marschman, S.C.

1990-05-01

A protective film is created about the anode within a cryolite-based electrolyte during electrolytic production of aluminum from alumina. The film functions to minimize corrosion of the anode by the cryolitic electrolyte and thereby extend the life of the anode. Various operating parameters of the electrolytic process are controlled to maintain the protective film about the anode in a protective state throughout the electrolytic reduction of alumina. Such parameters include electrolyte temperature, electrolyte ratio, current density, and Al[sub 2]O[sub 3] concentration. An apparatus is also disclosed to enable identification of the onset of anode corrosion due to disruption of the film to provide real time information regarding the state of the film. 3 figs.

Field Testing of High Current Electrokinetic Nanoparticle Treatment for Corrosion Mitigation in Reinforced Concrete

NASA Technical Reports Server (NTRS)

Cardenas, Henry; Alexander, Joshua; Kupwade-Patil, Kunal; Calle, Luz marina

2010-01-01

Electrokinetic Nanoparticle (EN) treatment was used as a rapid repair measure to mitigate chloride induced corrosion of reinforced concrete in the field. EN treatment uses an electric field to transport positively charged nanoparticles to the reinforcement through the concrete capillary pores. Cylindrical reinforced concrete specimens were batched with 4.5 wt % salt content (based on cement mass). Three distinct electrokinetic treatments were conducted using high current density (up to 5 A/m2) to form a chloride penetration barrier that was established in 5 days, as opposed to the traditional 6-8 weeks, generally required for electrochemical chloride extraction (ECE). These treatments included basic EN treatment, EN with additional calcium treatment, and basic ECE treatment. Field exposures were conducted at the NASA Beachside Corrosion Test Site, Kennedy Space Center, Florida, USA. The specimens were subjected to sea water immersion at the test site as a posttreatment exposure. Following a 30-day post-treatment exposure period, the specimens were subjected to indirect tensile testing to evaluate treatment impact. The EN treated specimens exhibited 60% and 30% increases in tensile strength as compared to the untreated controls and ECE treated specimens respectively. The surfaces of the reinforcement bars of the control specimens were 67% covered by corrosion products. In contrast, the EN treated specimens exhibited corrosion coverage of only 4%. Scanning electron microscopy (SEM) revealed a dense concrete microstructure adjacent to the bars of the treated specimens as compared to the control and ECE specimens. Energy dispersive spectroscopic (EDS) analysis of the polished EN treated specimens showed a reduction in chloride content by a factor of 20 adjacent to the bars. This study demonstrated that EN treatment was successful in forming a chloride penetration barrier rapidly. This work also showed that the chloride barrier was effective when samples were exposed to field conditions at one of the most severely corrosive environments in North America.

DEVELOPMENT OF AN ENVIRONMENTALLY BENIGN MICROBIAL INHIBITOR TO CONTROL INTERNAL PIPELINE CORROSION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bill W. Bogan; Brigid M. Lamb; John J. Kilbane II

2004-10-30

The overall program objective is to develop and evaluate environmentally benign agents or products that are effective in the prevention, inhibition, and mitigation of microbially influenced corrosion (MIC) in the internal surfaces of metallic natural gas pipelines. The goal is to develop one or more environmentally benign (a.k.a. ''green'') products that can be applied to maintain the structure and dependability of the natural gas infrastructure. Previous testing indicated that the growth, and the metal corrosion caused by pure cultures of sulfate reducing bacteria were inhibited by hexane extracts of some pepper plants. This quarter tests were performed to determine ifmore » chemical compounds other than pepper extracts could inhibit the growth of corrosion-associated microbes and to determine if pepper extracts and other compounds can inhibit corrosion when mature biofilms are present. Several chemical compounds were shown to be capable of inhibiting the growth of corrosion-associated microorganisms, and all of these compounds limited the amount of corrosion caused by mature biofilms to a similar extent. It is difficult to control corrosion caused by mature biofilms, but any compound that disrupts the metabolism of any of the major microbial groups present in corrosion-associated biofilms shows promise in limiting the amount/rate of corrosion.« less

Evidence of biogenic corrosion of titanium after exposure to a continuous culture of thiobacillus ferrooxidans grown in thiosulfate medium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Horn, J M; Martin, S I; Masterson, B

2000-12-07

Experiments were undertaken to evaluate extreme conditions under which candidate materials intended for use in a proposed nuclear waste repository might be susceptible to corrosion by endogenous microorganisms. Thiobucillus ferrooxidans, a sulfur-oxidizing bacterium, was grown in continuous culture using thiosulfate as an energy source; thiosulfate is oxidized to sulfate as a metabolic endproduct by this organism. Culture conditions were optimized to produce a high-density, metabolically active culture throughout a period of long term incubation in the presence of Alloy 22 (a high nickel-based alloy) and Titanium grade 7 (Tigr7) material coupons. After seven months incubation under these conditions, material couponsmore » were withdrawn and analyzed by high resolution microscopy and energy dispersive x-ray analyses. Alloy 22 coupons showed no detectable signs of corrosion. Tigr7, however, demonstrated distinct roughening of the coupon surface, and [presumably solubilized and precipitated] titanium was detected on Alloy 22 coupons incubated in the same T. ferrooxiduns culture vessel. Control coupons of these materials incubated in sterile thiosulfate medium did not demonstrate any signs of corrosion, thus showing that observed corrosive effects were due to the T. ferrooxidans metabolic activities. T. ferrooxidans intermediates of thiosulfate oxidation or sulfate may have caused the corrosive effects observed on Tigr7.« less

Case study: Minimization of corrosion using activated sodium bromide in a medium-size cooling tower

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nalepa, C.J.; Moore, R.M.; Golson, G.L.

1996-10-01

The process loop cooling tower at the Albemarle Process Development Center in Baton Rouge, LA has historically used chlorine as the biocide together with industry accepted phosphorus-based corrosion/scale inhibitors. Although this regimen provided biocontrol, sludge and iron build-up was a recurring problem, especially in low-velocity, small cross-sectional areas of piping. A general clean-up of the system was performed in April, 1995. This clean-up was followed with a switch to a two-component corrosion inhibitor/dispersant package. It was decided to study alternate biocides as well at this time. Activated sodium bromide was found to be particularly effective in this tower, which operatesmore » at pH {approximately}8.4. Relative to chlorine, the use of activated sodium bromide led to a decrease in general and pitting corrosion on mild steel while maintaining prior performance on admiralty brass. The reduced corrosion appears to be due to a combination of both chemical (less attack on passivated metal surfaces) and biological factors (better control of heterotrophic and sessile bacteria). These conclusions are supported by chemical analyses, corrosion meter and coupon data, dip slides, BART (biological activity reaction test) tests, and visual observations of the tower sump and heat exchanger surfaces.« less

Numerical Simulation of Monitoring Corrosion in Reinforced Concrete Based on Ultrasonic Guided Waves

PubMed Central

Zheng, Zhupeng; Lei, Ying; Xue, Xin

2014-01-01

Numerical simulation based on finite element method is conducted to predict the location of pitting corrosion in reinforced concrete. Simulation results show that it is feasible to predict corrosion monitoring based on ultrasonic guided wave in reinforced concrete, and wavelet analysis can be used for the extremely weak signal of guided waves due to energy leaking into concrete. The characteristic of time-frequency localization of wavelet transform is adopted in the corrosion monitoring of reinforced concrete. Guided waves can be successfully used to identify corrosion defects in reinforced concrete with the analysis of suitable wavelet-based function and its scale. PMID:25013865

The Corrosion and Corrosion Fatigue Behavior of Nickel Based Alloy Weld Overlay and Coextruded Claddings

NASA Astrophysics Data System (ADS)

Stockdale, Andrew

The use of low NOx boilers in coal fired power plants has resulted in sulfidizing corrosive conditions within the boilers and a reduction in the service lifetime of the waterwall tubes. As a solution to this problem, Ni-based weld overlays are used to provide the necessary corrosion resistance however; they are susceptible to corrosion fatigue. There are several metallurgical factors which give rise to corrosion fatigue that are associated with the localized melting and solidification of the weld overlay process. Coextruded coatings offer the potential for improved corrosion fatigue resistance since coextrusion is a solid state coating process. The corrosion and corrosion fatigue behavior of alloy 622 weld overlays and coextruded claddings was investigated using a Gleeble thermo-mechanical simulator retrofitted with a retort. The experiments were conducted at a constant temperature of 600°C using a simulated combustion gas of N2-10%CO-5%CO2-0.12%H 2S. An alternating stress profile was used with a minimum tensile stress of 0 MPa and a maximum tensile stress of 300 MPa (ten minute fatigue cycles). The results have demonstrated that the Gleeble can be used to successfully simulate the known corrosion fatigue cracking mechanism of Ni-based weld overlays in service. Multilayer corrosion scales developed on each of the claddings that consisted of inner and outer corrosion layers. The scales formed by the outward diffusion of cations and the inward diffusion of sulfur and oxygen anions. The corrosion fatigue behavior was influenced by the surface finish and the crack interactions. The initiation of a large number of corrosion fatigue cracks was not necessarily detrimental to the corrosion fatigue resistance. Finally, the as-received coextruded cladding exhibited the best corrosion fatigue resistance.

Nanoscale Reinforced, Polymer Derived Ceramic Matrix Coatings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rajendra Bordia

The goal of this project was to explore and develop a novel class of nanoscale reinforced ceramic coatings for high temperature (600-1000 C) corrosion protection of metallic components in a coal-fired environment. It was focused on developing coatings that are easy to process and low cost. The approach was to use high-yield preceramic polymers loaded with nano-size fillers. The complex interplay of the particles in the polymer, their role in controlling shrinkage and phase evolution during thermal treatment, resulting densification and microstructural evolution, mechanical properties and effectiveness as corrosion protection coatings were investigated. Fe-and Ni-based alloys currently used in coal-firedmore » environments do not possess the requisite corrosion and oxidation resistance for next generation of advanced power systems. One example of this is the power plants that use ultra supercritical steam as the working fluid. The increase in thermal efficiency of the plant and decrease in pollutant emissions are only possible by changing the properties of steam from supercritical to ultra supercritical. However, the conditions, 650 C and 34.5 MPa, are too severe and result in higher rate of corrosion due to higher metal temperatures. Coating the metallic components with ceramics that are resistant to corrosion, oxidation and erosion, is an economical and immediate solution to this problem. Good high temperature corrosion protection ceramic coatings for metallic structures must have a set of properties that are difficult to achieve using established processing techniques. The required properties include ease of coating complex shapes, low processing temperatures, thermal expansion match with metallic structures and good mechanical and chemical properties. Nanoscale reinforced composite coatings in which the matrix is derived from preceramic polymers have the potential to meet these requirements. The research was focused on developing suitable material systems and processing techniques for these coatings. In addition, we investigated the effect of microstructure on the mechanical properties and oxidation protection ability of the coatings. Coatings were developed to provide oxidation protection to both ferritic and austentic alloys and Ni-based alloys. The coatings that we developed are based on low viscosity pre-ceramic polymers. Thus they can be easily applied to any shape by using a variety of techniques including dip-coating, spray-coating and painting. The polymers are loaded with a variety of nanoparticles. The nanoparticles have two primary roles: control of the final composition and phases (and hence the properties); and control of the shrinkage during thermal decomposition of the polymer. Thus the selection of the nanoparticles was the most critical aspect of this project. Based on the results of the processing studies, the performance of selected coatings in oxidizing conditions (both static and cyclic) was investigated.« less

Optimal Corrosion Control Treatment Evaluation Technical Recommendations

EPA Pesticide Factsheets

This document provides technical recommendations that both systems and primacy agencies can use to comply with LCR CCT requirements and effective evaluation and designation of optimal corrosion control treatment (OCCT).

Response of microbial growth to orthophosphate and organic carbon influx in copper and plastic based plumbing water systems.

PubMed

Park, Se-Keun; Kim, Yeong-Kwan; Choi, Sung-Chan

2008-07-01

Consequences of orthophosphate addition for corrosion control in water distribution pipes with respect to microbial growth were investigated using batch and dynamic tests. Batch tests showed that the release of copper in either low or high organic carbon content water was decreased by 69% and 56% with addition 206 microg PO(4)-P, respectively. Dosing of orthophosphate against corrosion did not increase microbial growth potential in the water and in the biofilm in both corroded and uncorroded systems receiving tap water with a low content of organic carbon and of biodegradable organic fraction. However, in tap water having a high concentration of organic carbon from acetate addition, orthophosphate addition promoted the growth of bacteria, allowed more bacteria to assemble on corroded and uncorroded surfaces, and increased the consumption of organic carbon. Orthophosphate consumption did not exceed 1% of the amount of easily biodegradable organic carbon required for microbial growth, and the orthophosphate demand for corrosion control greatly exceeded the nutritional requirement of microbial growth. The results of the dynamic tests demonstrated that there was a significant effect of interaction between biodegradable organic carbon and orthophosphate on biofilm growth, whereby the effect of orthophosphate flux on microbial growth was dependent on the levels of biodegradable organic carbon. Controlling an easily biodegradable organic carbon would be therefore necessary to minimize the microbial growth potential induced by orthophosphate-based anticorrosion treatment.

Prediction of Failure Due to Thermal Aging, Corrosion and Environmental Fracture in Amorphous and Titanium Alloys

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farmer, J C

2003-04-15

DARPA is exploring a number of advanced materials for military applications, including amorphous metals and titanium-based alloys. Equipment made from these materials can undergo degradation due to thermal aging, uniform corrosion, pitting, crevice corrosion, denting, stress corrosion cracking, corrosion fatigue, hydrogen induced cracking and microbial influenced corrosion. Amorphous alloys have exceptional resistance to corrosion, due in part to the absence of grain boundaries, but can undergo crystallization and other phase instabilities during heating and welding. Titanium alloys are extremely corrosion resistant due to the formation of a tenacious passive film of titanium oxide, but is prone to hydrogen absorption inmore » crevices, and hydrogen induced cracking after hydrogen absorption. Accurate predictions of equipment reliability, necessary for strategic planning, requires integrated models that account for all relevant modes of attack, and that can make probabilistic predictions. Once developed, model parameters must be determined experimentally, and the validity of models must be established through careful laboratory and field tests. Such validation testing requires state-of-the-art surface analytical techniques, as well as electrochemical and fracture mechanics tests. The interaction between those processes that perturb the local environment on a surface and those that alter metallurgical condition must be integrated in predictive models. The material and environment come together to drive various modes of corrosive attack (Figure 1). Models must be supported through comprehensive materials testing capabilities. Such capabilities are available at LLNL and include: the Long Term Corrosion Test Facility (LTCTF) where large numbers of standard samples can be exposed to realistic test media at several temperature levels; a reverse DC machine that can be used to monitor the propagation of stress corrosion cracking (SCC) in situ; and banks of potentiostats with temperature controlled cells for potentiostatic and potentiodynamic testing (Figure 2).« less

Corrosion products of carbonation induced corrosion in existing reinforced concrete facades

DOE Office of Scientific and Technical Information (OSTI.GOV)

Köliö, Arto; Honkanen, Mari; Lahdensivu, Jukka

Active corrosion in reinforced concrete structures is controlled by environmental conditions and material properties. These factors determine the corrosion rate and type of corrosion products which govern the total achieved service life. The type and critical amount of corrosion products were studied by electron microscopy and X-ray diffractometry on concrete and reinforcement samples from existing concrete facades on visually damaged locations. The corrosion products in outdoor environment exposed concrete facades are mostly hydroxides (Feroxyhite, Goethite and Lepidocrocite) with a volume ratio to Fe of approximately 3. The results can be used to calibrate calculation of the critical corrosion penetration ofmore » concrete facade panels.« less

Smart aircraft fastener evaluation (SAFE) system: a condition-based corrosion detection system for aging aircraft

NASA Astrophysics Data System (ADS)

Schoess, Jeffrey N.; Seifert, Greg; Paul, Clare A.

1996-05-01

The smart aircraft fastener evaluation (SAFE) system is an advanced structural health monitoring effort to detect and characterize corrosion in hidden and inaccessible locations of aircraft structures. Hidden corrosion is the number one logistics problem for the U.S. Air Force, with an estimated maintenance cost of $700M per year in 1990 dollars. The SAFE system incorporates a solid-state electrochemical microsensor and smart sensor electronics in the body of a Hi-Lok aircraft fastener to process and autonomously report corrosion status to aircraft maintenance personnel. The long-term payoff for using SAFE technology will be in predictive maintenance for aging aircraft and rotorcraft systems, fugitive emissions applications such as control valves, chemical pipeline vessels, and industrial boilers. Predictive maintenance capability, service, and repair will replace the current practice of scheduled maintenance to substantially reduce operational costs. A summary of the SAFE concept, laboratory test results, and future field test plans is presented.

Demonstration of Antimicrobial Corrosion-Resisting Interior Coating Systems for Military Facilities in Warm, Humid Locations

DTIC Science & Technology

2017-06-01

ER D C/ CE RL T R- 17 -1 9 DoD Corrosion Prevention and Control Program Demonstration of Antimicrobial Corrosion- Resisting Interior ...Demonstration of Antimicrobial Corrosion- Resisting Interior Coating Systems for Military Facilities in Warm, Humid Locations Final Report on...Under Project F10-AR04, “Application of New Corrosion-Resistant Mold Abatement Technologies for Interior Surfaces of Buildings at Fort Polk, LA” ERDC

Lamb-Wave-Based Tomographic Imaging Techniques for Hole-Edge Corrosion Monitoring in Plate Structures

PubMed Central

Wang, Dengjiang; Zhang, Weifang; Wang, Xiangyu; Sun, Bo

2016-01-01

This study presents a novel monitoring method for hole-edge corrosion damage in plate structures based on Lamb wave tomographic imaging techniques. An experimental procedure with a cross-hole layout using 16 piezoelectric transducers (PZTs) was designed. The A0 mode of the Lamb wave was selected, which is sensitive to thickness-loss damage. The iterative algebraic reconstruction technique (ART) method was used to locate and quantify the corrosion damage at the edge of the hole. Hydrofluoric acid with a concentration of 20% was used to corrode the specimen artificially. To estimate the effectiveness of the proposed method, the real corrosion damage was compared with the predicted corrosion damage based on the tomographic method. The results show that the Lamb-wave-based tomographic method can be used to monitor the hole-edge corrosion damage accurately. PMID:28774041

49 CFR 195.581 - Which pipelines must I protect against atmospheric corrosion and what coating material may I use?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Which pipelines must I protect against atmospheric... Corrosion Control § 195.581 Which pipelines must I protect against atmospheric corrosion and what coating... the prevention of atmospheric corrosion. (c) Except portions of pipelines in offshore splash zones or...

49 CFR 195.581 - Which pipelines must I protect against atmospheric corrosion and what coating material may I use?

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Which pipelines must I protect against atmospheric... Corrosion Control § 195.581 Which pipelines must I protect against atmospheric corrosion and what coating... the prevention of atmospheric corrosion. (c) Except portions of pipelines in offshore splash zones or...

49 CFR 195.581 - Which pipelines must I protect against atmospheric corrosion and what coating material may I use?

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Which pipelines must I protect against atmospheric... Corrosion Control § 195.581 Which pipelines must I protect against atmospheric corrosion and what coating... the prevention of atmospheric corrosion. (c) Except portions of pipelines in offshore splash zones or...

Axenic aerobic biofilms inhibit corrosion of copper and aluminum.

PubMed

Jayaraman, A; Ornek, D; Duarte, D A; Lee, C C; Mansfeld, F B; Wood, T K

1999-11-01

The corrosion behavior of unalloyed copper and aluminum alloy 2024 in modified Baar's medium has been studied with continuous reactors using electrochemical impedance spectroscopy. An axenic aerobic biofilm of either Pseudomonas fragi K or Bacillus brevis 18 was able to lessen corrosion as evidenced by a consistent 20-fold increase in the low-frequency impedance value of copper as well as by a consistent four- to seven-fold increase in the polarization resistance of aluminum 2024 after six days exposure compared to sterile controls. This is the first report of axenic aerobic biofilms inhibiting generalized corrosion of copper and aluminum. Addition of the representative sulfate-reducing bacterium (SRB) Desulfovibrio vulgaris (to simulate consortia corrosion behavior) to either the P. fragi K or B. brevis 18 protective biofilm on copper increased the corrosion to that of the sterile control unless antibiotic (ampicillin) was added to inhibit the growth of SRB in the biofilm.

49 CFR 192.461 - External corrosion control: Protective coating.

Code of Federal Regulations, 2012 CFR

2012-10-01

... protective coating, whether conductive or insulating, applied for the purpose of external corrosion control... or damage from supporting blocks. (e) If coated pipe is installed by boring, driving, or other...

49 CFR 192.461 - External corrosion control: Protective coating.

Code of Federal Regulations, 2014 CFR

2014-10-01

... protective coating, whether conductive or insulating, applied for the purpose of external corrosion control... or damage from supporting blocks. (e) If coated pipe is installed by boring, driving, or other...

Rebar corrosion monitoring in concrete structure under salt water enviroment using fiber Bragg grating

NASA Astrophysics Data System (ADS)

Pan, Yuheng; Liu, Tiegen; Jiang, Junfeng; Liu, Kun; Wang, Shuang; He, Pan; Yan, Jinlin

2015-08-01

Monitoring corrosion of steel reinforcing bars is critical for the durability and safety of reinforced concrete structures. Corrosion sensors based on fiber optic have proved to exhibit meaningful benefits compared with the conventional electric ones. In recent years, Fiber Bragg Grating (FBG) has been used as a new kind of sensing element in an attempt to directly monitor the corrosion in concrete structure due to its remarkable advantages. In this paper, we present a novel kind of FBG based rebar corrosion monitoring sensor. The rebar corrosion is detected by volume expansion of the corroded rebar by transferring it to the axial strain of FBG when concrete structure is soaked in salt water. An accelerated salt water corrosion test was performed. The experiment results showed the corrosion can be monitored effectively and the corrosion rate is obtained by volume loss rate of rebar.

A Corrosion Control Manual for Rail Rapid Transit

NASA Technical Reports Server (NTRS)

Gilbert, L. O.; Fitzgerald, J. H., III; Menke, J. T.; Lizak, R. M. (Editor)

1982-01-01

This manual addresses corrosion problems in the design, contruction, and maintenance of rapid transit systems. Design and maintenance solutions are provided for each problem covered. The scope encompasses all facilities of urban rapid transit systems: structures and tracks, platforms and stations, power and signals, and cars. The types of corrosion and their causes as well as rapid transit properties are described. Corrosion control committees, and NASA, DOD, and ASTM specifications and design criteria to which reference is made in the manual are listed. A bibliography of papers and excerpts of reports is provided and a glossary of frequently used terms is included.

Launch Pad Coatings for Smart Corrosion Control

NASA Technical Reports Server (NTRS)

Calle, Luz M.; Hintze, Paul E.; Bucherl, Cori N.; Li, Wenyan; Buhrow, Jerry W.; Curran, Jerome P.; Whitten, Mary C.

2010-01-01

Corrosion is the degradation of a material as a result of its interaction with the environment. The environment at the KSC launch pads has been documented by ASM International (formerly American Society for Metals) as the most corrosive in the US. The 70 tons of highly corrosive hydrochloric acid that are generated by the solid rocket boosters during a launch exacerbate the corrosiveness of the environment at the pads. Numerous failures at the pads are caused by the pitting of stainless steels, rebar corrosion, and the degradation of concrete. Corrosion control of launch pad structures relies on the use of coatings selected from the qualified products list (QPL) of the NASA Standard 5008A for Protective Coating of Carbon Steel, Stainless Steel, and Aluminum on Launch Structures, Facilities, and Ground Support Equipment. This standard was developed to establish uniform engineering practices and methods and to ensure the inclusion of essential criteria in the coating of ground support equipment (GSE) and facilities used by or for NASA. This standard is applicable to GSE and facilities that support space vehicle or payload programs or projects and to critical facilities at all NASA locations worldwide. Environmental regulation changes have dramatically reduced the production, handling, use, and availability of conventional protective coatings for application to KSC launch structures and ground support equipment. Current attrition rate of qualified KSC coatings will drastically limit the number of commercial off the shelf (COTS) products available for the Constellation Program (CxP) ground operations (GO). CxP GO identified corrosion detection and control technologies as a critical, initial capability technology need for ground processing of Ares I and Ares V to meet Constellation Architecture Requirements Document (CARD) CxP 70000 operability requirements for reduced ground processing complexity, streamlined integrated testing, and operations phase affordability. Researchers at NASA's Corrosion Technology Laboratory at KSC are developing a smart, environmentally friendly coating system for early corrosion detection, inhibition, and self healing of mechanical damage without external intervention. This smart coating will detect and respond actively to corrosion and mechanical damage such as abrasion and scratches, in a functional and predictable manner, and will be capable of adapting its properties dynamically. This coating is being developed using corrosion sensitive microcapsules that deliver the contents of their core (corrosion inhibiting compounds, corrosion indicators, and self healing agents) on demand when corrosion or mechanical damage to the coating occurs.

PH and Electrochemical Responsive Materials for Corrosion Smart Coating Applications

NASA Technical Reports Server (NTRS)

Li, Wenyan; Calle, Luz M.

2008-01-01

Corrosion is a costly issue for military operations and civil industries. While most corrosion initiates from localized corrosion form, such as pitting, failure directly caused by localized corrosion is the most dangerous kind, because it is difficult to anticipate and prevent, occurs very suddenly and can be catastrophic. One way of preventing these failures is with a coating that can detect and heal localized corrosion. pH and other electrochemical changes are often associated with localized corrosion, so it is expected that materials that are pH or otherwise electrochemical responsive can be used to detect and control corrosion. This paper will review various pH and electrochemical responsive materials and their potential applications in corrosion smart coatings. Current research results in this field will also be reported.

LabVIEW 2010 Computer Vision Platform Based Virtual Instrument and Its Application for Pitting Corrosion Study

PubMed Central

Ramos, Rogelio; Zlatev, Roumen; Valdez, Benjamin; Stoytcheva, Margarita; Carrillo, Mónica; García, Juan-Francisco

2013-01-01

A virtual instrumentation (VI) system called VI localized corrosion image analyzer (LCIA) based on LabVIEW 2010 was developed allowing rapid automatic and subjective error-free determination of the pits number on large sized corroded specimens. The VI LCIA controls synchronously the digital microscope image taking and its analysis, finally resulting in a map file containing the coordinates of the detected probable pits containing zones on the investigated specimen. The pits area, traverse length, and density are also determined by the VI using binary large objects (blobs) analysis. The resulting map file can be used further by a scanning vibrating electrode technique (SVET) system for rapid (one pass) “true/false” SVET check of the probable zones only passing through the pit's centers avoiding thus the entire specimen scan. A complete SVET scan over the already proved “true” zones could determine the corrosion rate in any of the zones. PMID:23691434

49 CFR 193.2635 - Monitoring corrosion control.

Code of Federal Regulations, 2010 CFR

2010-10-01

....2635 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2635 Monitoring corrosion control...

Surface modification of a biodegradable magnesium alloy with phosphorylcholine (PC) and sulfobetaine (SB) functional macromolecules for reduced thrombogenicity and acute corrosion resistance.

PubMed

Ye, Sang-Ho; Jang, Yong-Seok; Yun, Yeo-Heung; Shankarraman, Venkat; Woolley, Joshua R; Hong, Yi; Gamble, Lara J; Ishihara, Kazuhiko; Wagner, William R

2013-07-02

Siloxane functionalized phosphorylcholine (PC) or sulfobetaine (SB) macromolecules (PCSSi or SBSSi) were synthesized to act as surface modifying agents for degradable metallic surfaces to improve acute blood compatibility and slow initial corrosion rates. The macromolecules were synthesized using a thiol-ene radical photopolymerization technique and then utilized to modify magnesium (Mg) alloy (AZ31) surfaces via an anhydrous phase deposition of the silane functional groups. X-ray photoelectron spectroscopy surface analysis results indicated successful surface modification based on increased nitrogen and phosphorus or sulfur composition on the modified surfaces relative to unmodified AZ31. In vitro acute thrombogenicity assessment after ovine blood contact with the PCSSi and SBSSi modified surfaces showed a significant decrease in platelet deposition and bulk phase platelet activation compared with the control alloy surfaces. Potentiodynamic polarization and electrochemical impedance spectroscopy data obtained from electrochemical corrosion testing demonstrated increased corrosion resistance for PCSSi- and SBSSi-modified AZ31 versus unmodified surfaces. The developed coating technique using PCSSi or SBSSi showed promise in acutely reducing both the corrosion and thrombotic processes, which would be attractive for application to blood contacting devices, such as vascular stents, made from degradable Mg alloys.

Corrosion in artificial saliva of a Ni-Cr-based dental alloy joined by TIG welding and conventional brazing.

PubMed

Matos, Irma C; Bastos, Ivan N; Diniz, Marília G; de Miranda, Mauro S

2015-08-01

Fixed prosthesis and partial dental prosthesis frameworks are usually made from welded Ni-Cr-based alloys. These structures can corrode in saliva and have to be investigated to establish their safety. The purpose of this study was to evaluate the corrosion behavior of joints joined by tungsten inert gas (TIG) welding and conventional brazing in specimens made of commercial Ni-Cr alloy in Fusayama artificial saliva at 37°C (pH 2.5 and 5.5). Eighteen Ni-Cr base metal specimens were cast and welded by brazing or tungsten inert gas methods. The specimens were divided into 3 groups (base metal, 2 welded specimens), and the composition and microstructure were qualitatively evaluated. The results of potential corrosion and corrosion current density were analyzed with a 1-way analysis of variance and the Tukey test for pairwise comparisons (α=.05). Base metal and tungsten inert gas welded material showed equivalent results in electrochemical corrosion tests, while the air-torched specimens exhibited low corrosion resistance. The performance was worst at pH 2.5. These results suggest that tungsten inert gas is a suitable welding process for use in dentistry, because the final microstructure does not reduce the corrosion resistance in artificial saliva at 37°C, even in a corrosion-testing medium that facilitates galvanic corrosion processes. Moreover, the corrosion current density of brazed Ni-Cr alloy joints was significantly higher (P<.001) than the base metal and tungsten inert gas welded joints. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Studying localized corrosion using liquid cell transmission electron microscopy

DOE PAGES

Chee, See Wee; Pratt, Sarah H.; Hattar, Khalid; ...

2014-11-07

Using liquid cell transmission electron microscopy (LCTEM), localized corrosion of Cu and Al thin films immersed in aqueous NaCl solutions was studied. We demonstrate that potentiostatic control can be used to initiate pitting and that local compositional changes, due to focused ion beam implantation of Au + ions, can modify the corrosion susceptibility of Al films. Likewise, a discussion on strategies to control the onset of pitting is also presented.

Microbiologically Influenced Corrosion: Causative Organisms and Mechanisms

DTIC Science & Technology

2012-01-31

corrosion is both predictable and complex. In aquatic environments and under some atmospheric conditions . microorganisms settle on surfaces and alter the...some atmospheric conditions , microorganisms settle on sin laces and alter the surface chemistry controlling the rates of corrosion or shifting the...pitting corrosion of some allO) S continues under deposits of iron-oxidizing bacteria independent of bacterial activity. Similarly, microbiologicall

The role of lipopolysaccharide on the electrochemical behavior of titanium.

PubMed

Barão, V A; Mathew, M T; Assunção, W G; Yuan, J C; Wimmer, M A; Sukotjo, C

2011-05-01

Lipopolysaccharide (LPS) may induce peri-implantitis and implant failure. However, the role of LPS in titanium (Ti) electrochemical behavior remains unknown. We hypothesized that LPS in saliva with different pHs affects Ti corrosion properties. Thirty-six Ti discs (15 mm × 3 mm) were divided into 12 groups according to saliva pH (3, 6.5, and 9) and Escherichia coli LPS concentration (0, 0.15, 15, and 150 µg/mL). Electrochemical tests, such as open circuit potential, potentiodynamic, and electrochemical impedance spectroscopy, were conducted in a controlled environment. Data were evaluated by Pearson correlation and regression analysis (α = 0.05). LPS and pH affected Ti corrosive behavior. In general, lower pH and higher LPS concentration accelerated Ti corrosion. In the control group, the increase of pH significantly reduced the corrosion rate and increased the capacitance of the double layer. In LPS groups, the decrease of pH significantly increased the corrosion rate of Ti. LPS negatively influenced Ti corrosion behavior. C(dl), capacitance of double layer; E(corr), corrosion potential; EIS, electrochemical impedance spectroscopy; I(corr), corrosion current density; I(pass), passivation current density; LPS, lipopolysaccharide; OCP, open circuit potential; R(p), polarization resistance; Ti, titanium.

Superhydrophobic Post Treatment and Coating Extenders for Improved Asset Sustainability

NASA Technical Reports Server (NTRS)

Trigwell, Steven; Montgomery, Eliza L.; Calle, Luz M.

2015-01-01

Launch structures, hardware, and ground support equipment, at NASA's John F. Kennedy Space Center in Florida, are exposed to a highly corrosive natural coastal marine environment. In addition, during launches, rocket exhaust deposition is also highly corrosive. Superhydrophobic coatings are being considered for additional corrosion protection on existing structures to enhance corrosion resistance and add an additional layer of protection against harsh environmental elements. These coatings have come into their own recently, and are now being investigated as corrosion protective coatings due to their water repelling capability. These coatings can be used on existing coatings, newly coated materials, or used on bare substrates. The coatings are not suitable for permanent corrosion protection, but can be used where additional corrosion control is desired or only when temporary corrosion control is needed, such as in hardware sitting on a launch pad for 30-45 days prior to a launch. In this study, superhydrophobic coatings were applied on various coated and uncoated substrates and exposed to the spaceport environment for various times up to 60 days. This paper highlights the current results of the superhydrophobic coatings performance evaluated by X-ray photoelectron spectroscopy, and contact angle measurements.

Rail base corrosion and cracking prevention

DOT National Transportation Integrated Search

2014-07-01

Rail base corrosion combined with fatigue or damage can significantly reduce rail life. Studies were done to examine the relative contribution of damage, corrosion, and fatigue on rail life. The combined effects can be separated into constituent fact...

The corrosion behavior of Fe-Mn-Al weld metals

NASA Astrophysics Data System (ADS)

Aidun, Daryush K.

2001-02-01

The corrosion resistance of a newly developed iron-base, Fe-Mn-Al austenitic, and duplex weld metal has been examined in the NACE solution consisting of 5 wt.% NaCl, 0.5 wt.% acetic acid, and the balance distilled water. The electrochemical techniques such as potentiodynamic polarization, Tafel plots, linear polarization, cyclic polarization, and open-circuit potential versus time were employed. The Fe-Mn-Al weld metals did not passivate and exhibited high corrosion rates. Fe-Cr-Ni (310 and 316) weld and base metals were also examined in the NACE solution at room temperature. The 310 and 316 base metals were more resistant to corrosion than the as-welded 310 and 316 weld metals. Postweld heat treatment (PWHT) improved the corrosion performance of the Fe-Mn-Al weld metals. The corrosion resistance of Fe-Mn-Al weld metals after PWHT was still inferior to that of the 310 and 316 weld and base metals.

A Micro-Mechanism-Based Continuum Corrosion Fatigue Damage Model for Steels

NASA Astrophysics Data System (ADS)

Sun, Bin; Li, Zhaoxia

2018-05-01

A micro-mechanism-based corrosion fatigue damage model is developed for studying the high-cycle corrosion fatigue of steel from multi-scale viewpoint. The developed physical corrosion fatigue damage model establishes micro-macro relationships between macroscopic continuum damage evolution and collective evolution behavior of microscopic pits and cracks, which can be used to describe the multi-scale corrosion fatigue process of steel. As a case study, the model is used to predict continuum damage evolution and number density of the corrosion pit and short crack of steel component in 5% NaCl water under constant stress amplitude at 20 kHz, and the numerical results are compared with experimental results. It shows that the model is effective and can be used to evaluate the continuum macroscopic corrosion fatigue damage and study microscopic corrosion fatigue mechanisms of steel.

A Micro-Mechanism-Based Continuum Corrosion Fatigue Damage Model for Steels

NASA Astrophysics Data System (ADS)

Sun, Bin; Li, Zhaoxia

2018-04-01

A micro-mechanism-based corrosion fatigue damage model is developed for studying the high-cycle corrosion fatigue of steel from multi-scale viewpoint. The developed physical corrosion fatigue damage model establishes micro-macro relationships between macroscopic continuum damage evolution and collective evolution behavior of microscopic pits and cracks, which can be used to describe the multi-scale corrosion fatigue process of steel. As a case study, the model is used to predict continuum damage evolution and number density of the corrosion pit and short crack of steel component in 5% NaCl water under constant stress amplitude at 20 kHz, and the numerical results are compared with experimental results. It shows that the model is effective and can be used to evaluate the continuum macroscopic corrosion fatigue damage and study microscopic corrosion fatigue mechanisms of steel.

49 CFR 195.555 - What are the qualifications for supervisors?

Code of Federal Regulations, 2010 CFR

2010-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.555 What are the... that portion of the corrosion control procedures established under § 195.402(c)(3) for which they are...

49 CFR 195.555 - What are the qualifications for supervisors?

Code of Federal Regulations, 2011 CFR

2011-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.555 What are the... that portion of the corrosion control procedures established under § 195.402(c)(3) for which they are...

49 CFR 195.555 - What are the qualifications for supervisors?

Code of Federal Regulations, 2013 CFR

2013-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.555 What are the... that portion of the corrosion control procedures established under § 195.402(c)(3) for which they are...

49 CFR 195.555 - What are the qualifications for supervisors?

Code of Federal Regulations, 2012 CFR

2012-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.555 What are the... that portion of the corrosion control procedures established under § 195.402(c)(3) for which they are...

49 CFR 195.555 - What are the qualifications for supervisors?

Code of Federal Regulations, 2014 CFR

2014-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.555 What are the... that portion of the corrosion control procedures established under § 195.402(c)(3) for which they are...

49 CFR 193.2304 - Corrosion control overview.

Code of Federal Regulations, 2010 CFR

2010-10-01

....2304 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Construction § 193.2304 Corrosion control overview. (a...

49 CFR 193.2631 - Internal corrosion control.

Code of Federal Regulations, 2010 CFR

2010-10-01

....2631 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2631 Internal corrosion control. Each...

INTERNAL CORROSION AND DEPOSITION CONTROL

EPA Science Inventory

Corrosion is one of the most important problems in the drinking water industry. It can affect public health, public acceptance of a water supply, and the cost of providing safe water. Deterioration of materials resulting from corrosion can necessitate huge yearly expenditures o...

Fireside corrosion in kraft recovery boilers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tran, H.N.; Barham, D.; Hupa, M.

1988-01-01

Causes and corrective measures are reviewed for several common types of fireside corrosion in kraft recovery boilers. Corrosion differs significantly with location in the boiler due tio the great differences in metal surface temperature and deposit and flue gas chemistry. Sulphidation corrosion associated with sulphur-bearing gases under reducing conditions is dominant in the lower furnace, while sulphidation/oxidation resulting from gas-deposit-metal reactions is important in the upper boiler. In many cases, although corrosion has been controlled by ensuring the absence of a molten phase at the metal surface, the corrosion mechanism is not fully understood.

Proceedings of the Tri-Service Conference on Corrosion Held in Atlantic City, New Jersey on 17-19 October 1989

DTIC Science & Technology

1989-10-19

installation. 4. Corrosion inhibiting compounds need to be applied in the final assealbly of models to all corrosion prone areas of the structure, e.g...Figure 12 shows an example of poor surface treatment of a previously repaired stringer area. Application of a corrosion inhibiting compound may have... compounds and a good corrosion control maintenance program. REFERENCE U. G. Goranson and M. Miller, "Aging Fleet - Aging Fleet Evaluation Program

Sampling for Lead in Drinking Water

EPA Science Inventory

Sampling protocols for lead in water can be broadly categorized based on their intended purpose of 1) Pb regulatory compliance/corrosion control efficacy, 2) Pb plumbing source determination or Pb type identification, and 3) Pb exposure assessment. Choosing the appropriate protoc...

Rail Base Corrosion and Cracking Prevention: Phase 2

DOT National Transportation Integrated Search

2018-04-09

EWI was engaged by the Federal Railroad Administration to research rail treatments to prevent rail base corrosion in corrosive environments. A coating system was selected in Phase 1 and recommended for field trials. In Phase 2, four railroads sponsor...

Thermal control system corrosion study

NASA Technical Reports Server (NTRS)

Yee, Robert; Folsom, Rolfe A.; Mucha, Phillip E.

1990-01-01

During the development of an expert system for autonomous control of the Space Station Thermal Control System (TCS), the thermal performance of the Brassboard TCS began to gradually degrade. This degradation was due to filter clogging by metallic residue. A study was initiated to determine the source of the residue and the basic cause of the corrosion. The investigation focused on the TCS design, materials compatibility, Ames operating and maintenance procedures, and chemical analysis of the residue and of the anhydrous ammonia used as the principal refrigerant. It was concluded that the corrosion mechanisms involved two processes: the reaction of water alone with large, untreated aluminum parts in a high pH environment and the presence of chlorides and chloride salts. These salts will attack the aluminum oxide layer and may enable galvanic corrosion between the aluminum and the more noble stainless steel and other metallic elements present. Recommendations are made for modifications to the system design, the materials used, and the operating and maintenance procedures, which should largely prevent the recurrence of these corrosion mechanisms.

Non-Chromate, ZVOC Coatings for Steel Substrates on Army and Navy Aircraft and Ground Vehicles

DTIC Science & Technology

2014-12-01

Control and Prevention Executive CHPPM Center for Health Promotion and Preventive Medicine CPAC corrosion prevention and control DI deionized...inhibitors, such as the Cheminhib 420, are used on both Stryker and MRAP to prevent corrosion prior to painting. Two of the alternatives, Oxsilan 9810/2 and...and pretreatments that the Army currently uses to mitigate corrosion contain toxic heavy metals, volatile organic compounds (VOC), and hazardous air

Developing a Systematic Corrosion Control Evaluation Approach in Flint

EPA Science Inventory

Presentation covers what the projects were that were recommended by the Flint Safe Drinking Water Task Force for corrosion control assessment for Flint, focusing on the sequential sampling project, the pipe rigs, and pipe scale analyses.

Radio Frequency Identification (RFID) Based Corrosion Monitoring Sensors. Part 2: Application and Testing of the Coating Materials

DTIC Science & Technology

2014-12-22

Radio frequency identification ( RFID ) based corrosion monitoring sensors: Part II Application and testing of the coating materials Youliang He1...email: yohe@nrcan.gc.ca Keywords: Corrosion monitoring; Wireless sensor; RFID ; Electromagnetic interference; Coating. Abstract Cost-effective...Radio Frequency Identification ( RFID ) transponders (tags) were investigated for wireless corrosion monitoring by applying a metal-filled conductive

49 CFR 193.2629 - External corrosion control: buried or submerged components.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2629 External... external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

Microstructure and Corrosion Characterization of Squeeze Cast AM50 Magnesium Alloys

NASA Astrophysics Data System (ADS)

Sachdeva, Deepika; Tiwari, Shashank; Sundarraj, Suresh; Luo, Alan A.

2010-12-01

Squeeze casting of magnesium alloys potentially can be used in lightweight chassis components such as control arms and knuckles. This study documents the microstructural analysis and corrosion behavior of AM50 alloys squeeze cast at different pressures between 40 and 120 MPa and compares them with high-pressure die cast (HPDC) AM50 alloy castings and an AM50 squeeze cast prototype control arm. Although the corrosion rates of the squeeze cast samples are slightly higher than those observed for the HPDC AM50 alloy, the former does produce virtually porosity-free castings that are required for structural applications like control arms and wheels. This outcome is extremely encouraging as it provides an opportunity for additional alloy and process development by squeeze casting that has remained relatively unexplored for magnesium alloys compared with aluminum. Among the microstructural parameters analyzed, it seems that the β-phase interfacial area, indicating a greater degree of β network, leads to a lower corrosion rate. Weight loss was the better method for determining corrosion behavior in these alloys that contain a large fraction of second phase, which can cause perturbations to an overall uniform surface corrosion behavior.

Corrosion protection of galvanized steels by silane-based treatments

NASA Astrophysics Data System (ADS)

Yuan, Wei

The possibility of using silane coupling agents as replacements for chromate treatments was investigated on galvanized steel substrates. In order to understand the influence of deposition parameters on silane film formation, pure zinc substrates were first used as a model for galvanized steel to study the interaction between silane coupling agents and zinc surfaces. The silane films formed on pure zinc substrates from aqueous solutions were characterized by ellipsometry, contact angle measurements, reflection absorption infrared spectroscopy, x-ray photoelectron spectroscopy, and atomic force microscopy. The deposition parameters studied include solution concentration, solution dipping time and pH value of the applied solution. It appears that silane film formation involved a true equilibrium of hydrolysis and condensation reactions in aqueous solutions. It has been found that the silane film thickness obtained depends primarily on the solution concentration and is almost independent of the solution dipping time. The molecular orientation of applied silane films is determined by the pH value of applied silane solutions and the isoelectric point of metal substrates. The deposition window in terms of pH value for zinc substrates is between 6.0 and 9.0. The total surface energy of the silane-coated pure zinc substrates decreases with film aging time, the decrease rate, however, is determined by the nature of silane coupling agents. Selected silane coupling agents were applied as prepaint or passivation treatments onto galvanized steel substrates. The corrosion protection provided by these silane-based treatments were evaluated by salt spray test, cyclic corrosion test, electrochemical impedance spectroscopy, and stack test. The results showed that silane coupling agents can possibly be used to replace chromates for corrosion control of galvanized steel substrates. Silane coatings provided by these silane treatments serve mainly as physical barriers. Factors that affect the performance of a silane coupling agent in the application of corrosion control include chemical reactivity, hydrophobic character, siloxane crosslinker network, and film thickness. Good protections afforded by the silane treatments are a synergetic effect of all these factors.

Corrosion Mitigation Strategies - an Introduction

DTIC Science & Technology

2009-02-05

formed • Stress corrosion cracking Leaders in Corrosion Control Technology • Overpressure • Pressure of a gas over a liquid- solubility of gases in...Power surges • Crack protective films, fretting, fatique Design – Chemistry • Used to eliminate candidate materials • pH acidic (H+) basic (OH...Technology • Laboratory tests • Published data Mechanical Properties • Strength • Ductility • Environmental cracking Methods of Corrosion Control–Materials

Improvement of Adhesion Properties and Corrosion Resistance of Sol-Gel Coating on Zinc.

PubMed

Savignac, Pauline; Menu, Marie-Joëlle; Gressier, Marie; Denat, Bastien; Khadir, Yacine El; Manov, Stephan; Ansart, Florence

2018-05-03

Corrosion is a major problem for durability of many metals and alloys. Among the efficient classical surface treatments, chromate-based treatments must be banished from industrial use due to their toxicity. At the same time, sol-gel routes have demonstrated high potential to develop an efficient barrier effect against aggressive environments. By this process, the anti-corrosion property can be also associated to others in the case of the development of multi-functional hybrid coatings. In this paper, the main goal is precisely to improve both the corrosion resistance and the adhesion properties of phosphated zinc substrates by the deposition of a hybrid (organic-inorganic) sol-gel layer. To reach this double objective, a choice between two formulations 3-glycidoxypropyltrimethoxysilane (GPTMS)/aluminum-tri-sec-butoxide (ASB) and 3-(trimethoxysilyl)propylmethacrylate (MAP)/tetraethylorthosilicate (TEOS) was firstly made based on the results obtained by microstructural characterizations using SEM, optical analysis, and mechanical characterization such as shock and/or scratch tests (coupled to climatic chamber and salt spray exposure). Several investigations were performed in this study, and the best formulation and performances of the system were obtained by adding a new precursor (1-[3-(trimethoxysilyl)propyl]ureido-UPS) under controlled conditions, as detailed in this paper.

Evaluation of corrosion fatigue and life prediction of lower arm for automotive suspension component

NASA Astrophysics Data System (ADS)

Kim, Yong-Sang; Kim, Jung-Gu

2017-01-01

Lower arm is one of the suspension components of automobile. It is suffered from driving vibration and corrosive environment, namely corrosion fatigue. In this study, corrosion fatigue property of lower arm was investigated, and a modified model based on Palmgren-Miner rule was developed to predict the lifetimes of corrosion fatigue. The corrosion fatigue life of lower arm was about 1/6 times shorter than fatigue life. Based on the results of corrosion fatigue tests and meteorological data in Seoul and Halifax, the corrosion fatigue life of lower arm was predicted. The satisfaction of 10-year and 300,000 km warranty was dominated by the climate of automobile driving. This prediction indicates that the weather condition or driving condition influences the life of automotive parts. Therefore, to determine the warranty of automotive parts, the driving condition has to be carefully considered.

Maintainability Improvement Through Corrosion Prediction

DTIC Science & Technology

1997-12-01

Aluminum base alloys - Mechanical properties; Lithium- Alloying elements; Crack propagation- Corrosion effects ; Fatigue life - Corrosion... effects on the corrosion fatigue life of 7075-T6 aluminum alloy . Ma,L CORPORATE SOURCE: University of Utah JOURNAL: Dissertation Abstracts International...Diffusion effects ; Hydrogen- Diffusion SECTION HEADINGS: 64 (Corrosion) 52. 715866 87-640094 The Life Prediction for 2024

The effect of treatment temperature on corrosion resistance and hydrophilicity of an ionic liquid coating for Mg-based stents.

PubMed

Zhang, Yafei; Forsyth, Maria; Hinton, Bruce R W

2014-01-01

Mg alloys are attractive candidate materials for biodegradable stents. However, there are few commercially available Mg-based stents in clinical use because Mg alloys generally undergo rapid localized corrosion in the body. In this study, we report a new surface coating for Mg alloy AZ31 based on a low-toxicity ionic liquid (IL), tributyl(methyl)phosphonium diphenyl phosphate (P1,4,4,4 dpp), to control its corrosion rate. Emphasis is placed on the effect of treatment temperature. We showed that enhancing the treatment temperature provided remarkable improvements in the performances of both corrosion resistance and biocompatibility. Increasing treatment temperature resulted in a thicker (although still nanometer scale) and more homogeneous IL film on the surface. Scanning electron microscopy and optical profilometry observations showed that there were many large, deep pits formed on the surface of bare AZ31 after 2 h of immersion in simulated body fluid (SBF). The IL coating (particularly when formed at 100 °C for 1 h) significantly suppressed the formation of these pits on the surface, making corrosion occur more uniformly. The P1,4,4,4 dpp IL film formed at 100 °C was more hydrophilic than the bare AZ31 surface, which was believed to be beneficial for avoiding the deposition of the proteins and cells on the surface and therefore improving the biocompatibility of AZ31 in blood. The interaction mechanism between this IL and AZ31 was also investigated using ATR-FTIR, which showed that both anion and cation of this IL were present in the film, and there was a chemical interaction between dpp(-) anion and the surface of AZ31 during the film formation.

A high-specific-strength and corrosion-resistant magnesium alloy

NASA Astrophysics Data System (ADS)

Xu, Wanqiang; Birbilis, Nick; Sha, Gang; Wang, Yu; Daniels, John E.; Xiao, Yang; Ferry, Michael

2015-12-01

Ultra-lightweight alloys with high strength, ductility and corrosion resistance are desirable for applications in the automotive, aerospace, defence, biomedical, sporting and electronic goods sectors. Ductility and corrosion resistance are generally inversely correlated with strength, making it difficult to optimize all three simultaneously. Here we design an ultralow density (1.4 g cm-3) Mg-Li-based alloy that is strong, ductile, and more corrosion resistant than Mg-based alloys reported so far. The alloy is Li-rich and a solute nanostructure within a body-centred cubic matrix is achieved by a series of extrusion, heat-treatment and rolling processes. Corrosion resistance from the environment is believed to occur by a uniform lithium carbonate film in which surface coverage is much greater than in traditional hexagonal close-packed Mg-based alloys, explaining the superior corrosion resistance of the alloy.

A high-specific-strength and corrosion-resistant magnesium alloy.

PubMed

Xu, Wanqiang; Birbilis, Nick; Sha, Gang; Wang, Yu; Daniels, John E; Xiao, Yang; Ferry, Michael

2015-12-01

Ultra-lightweight alloys with high strength, ductility and corrosion resistance are desirable for applications in the automotive, aerospace, defence, biomedical, sporting and electronic goods sectors. Ductility and corrosion resistance are generally inversely correlated with strength, making it difficult to optimize all three simultaneously. Here we design an ultralow density (1.4 g cm(-3)) Mg-Li-based alloy that is strong, ductile, and more corrosion resistant than Mg-based alloys reported so far. The alloy is Li-rich and a solute nanostructure within a body-centred cubic matrix is achieved by a series of extrusion, heat-treatment and rolling processes. Corrosion resistance from the environment is believed to occur by a uniform lithium carbonate film in which surface coverage is much greater than in traditional hexagonal close-packed Mg-based alloys, explaining the superior corrosion resistance of the alloy.

Preparation of Si-containing oxide coating and biomimetic apatite induction on magnesium alloy

NASA Astrophysics Data System (ADS)

Yu, Huijun; Dong, Qing; Dou, Jinhe; Pan, Yaokun; Chen, Chuanzhong

2016-12-01

Magnesium and its alloys are recently found important in the field of bone repairing for their ideal mechanical performance and excellent biocompatibility. Micro-arc oxidation (MAO) is a simple, controllable and efficient electrochemistry method that can prepare protective ceramic coatings on magnesium alloys. The properties of the MAO coating, such as thickness, microstructure, roughness and composition, can easily be controlled by adjusting the voltage, current density, duration or the electrolyte concentration. In this work, MAO coatings are prepared on ZK61 magnesium alloy at different voltages. The structure characteristics and element distributions of the coating are investigated by XRD, TEM, SEM and EPMA. The MAO samples are immersed in SBF for 7, 14 and 28 days respectively. The corrosion behaviors of the samples in SBF were also investigated by potentiodynamic polarization curves. The corrosion products were characterized by EDS and FT-IR. The MAO coated ZK61 alloy samples showed excellent corrosion resistance and bioactivity. The MAO method demonstrates a great potential in the preparation of degradable and bioactive orthopedic magnesium-based implants.

Biofunctional composite coating architectures based on polycaprolactone and nanohydroxyapatite for controlled corrosion activity and enhanced biocompatibility of magnesium AZ31 alloy.

PubMed

Zomorodian, A; Garcia, M P; Moura E Silva, T; Fernandes, J C S; Fernandes, M H; Montemor, M F

2015-03-01

In this work a biofunctional composite coating architecture for controlled corrosion activity and enhanced cellular adhesion of AZ31 Mg alloys is proposed. The composite coating consists of a polycaprolactone (PCL) matrix modified with nanohydroxyapatite (HA) applied over a nanometric layer of polyetherimide (PEI). The protective properties of the coating were studied by electrochemical impedance spectroscopy (EIS), a non-disturbing technique, and the coating morphology was investigated by field emission scanning electron microscopy (FE-SEM). The results show that the composite coating protects the AZ31 substrate. The barrier properties of the coating can be optimized by changing the PCL concentration. The presence of nanohydroxyapatite particles influences the coating morphology and decreases the corrosion resistance. The biocompatibility was assessed by studying the response of osteoblastic cells on coated samples through resazurin assay, confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). The results show that the polycaprolactone to hydroxyapatite ratio affects the cell behavior and that the presence of hydroxyapatite induces high osteoblastic differentiation. Copyright © 2014 Elsevier B.V. All rights reserved.

EPA Optimal Corrosion Control Treatment Regional Training Workshops

EPA Pesticide Factsheets

EPA is hosting face-to-face regional training workshops throughout 2016-2017 on optimal corrosion control treatment (OCCT). These will be held at each of the Regions and is intended for primacy agency staff and technical assistance providers.

A strain-mediated corrosion model for bioabsorbable metallic stents.

PubMed

Galvin, E; O'Brien, D; Cummins, C; Mac Donald, B J; Lally, C

2017-06-01

This paper presents a strain-mediated phenomenological corrosion model, based on the discrete finite element modelling method which was developed for use with the ANSYS Implicit finite element code. The corrosion model was calibrated from experimental data and used to simulate the corrosion performance of a WE43 magnesium alloy stent. The model was found to be capable of predicting the experimentally observed plastic strain-mediated mass loss profile. The non-linear plastic strain model, extrapolated from the experimental data, was also found to adequately capture the corrosion-induced reduction in the radial stiffness of the stent over time. The model developed will help direct future design efforts towards the minimisation of plastic strain during device manufacture, deployment and in-service, in order to reduce corrosion rates and prolong the mechanical integrity of magnesium devices. The need for corrosion models that explore the interaction of strain with corrosion damage has been recognised as one of the current challenges in degradable material modelling (Gastaldi et al., 2011). A finite element based plastic strain-mediated phenomenological corrosion model was developed in this work and was calibrated based on the results of the corrosion experiments. It was found to be capable of predicting the experimentally observed plastic strain-mediated mass loss profile and the corrosion-induced reduction in the radial stiffness of the stent over time. To the author's knowledge, the results presented here represent the first experimental calibration of a plastic strain-mediated corrosion model of a corroding magnesium stent. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

SUMMARY REPORT ON CORROSIVITY STUDIES IN COINCINERATION OF SEWAGE SLUDGE AND SOLID WASTE

EPA Science Inventory

Corrosion probe exposures were conducted in the Harrisburg, Pennsylvania Incinerator to determine the effects of burning low-chloride sewage sludge with municipal refuse. Probes having controlled temperature gradients were used to measure corrosion rates for exposure times up to ...

49 CFR 192.483 - Remedial measures: General.

Code of Federal Regulations, 2011 CFR

2011-10-01

... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control... a buried or submerged pipeline because of external corrosion must have a properly prepared surface... external corrosion must be cathodically protected in accordance with this subpart. (c) Except for cast iron...

49 CFR 192.483 - Remedial measures: General.

Code of Federal Regulations, 2010 CFR

2010-10-01

... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control... a buried or submerged pipeline because of external corrosion must have a properly prepared surface... external corrosion must be cathodically protected in accordance with this subpart. (c) Except for cast iron...

49 CFR 192.483 - Remedial measures: General.

Code of Federal Regulations, 2014 CFR

2014-10-01

... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control... a buried or submerged pipeline because of external corrosion must have a properly prepared surface... external corrosion must be cathodically protected in accordance with this subpart. (c) Except for cast iron...

49 CFR 192.483 - Remedial measures: General.

Code of Federal Regulations, 2012 CFR

2012-10-01

... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control... a buried or submerged pipeline because of external corrosion must have a properly prepared surface... external corrosion must be cathodically protected in accordance with this subpart. (c) Except for cast iron...

49 CFR 192.483 - Remedial measures: General.

Code of Federal Regulations, 2013 CFR

2013-10-01

... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control... a buried or submerged pipeline because of external corrosion must have a properly prepared surface... external corrosion must be cathodically protected in accordance with this subpart. (c) Except for cast iron...

Demonstration of Electronic Capacitor-Based Water Treatment System for Application at Military Installations

DTIC Science & Technology

2009-07-01

45 7.1 Scale, corrosion, bacteria and biofilm control...isms to thrive, creating a potential scenario for microbially induced corro- sion (MIC), heat transfer losses due to biofilm deposits, and potential...health hazards due to pathogenic bacteria growing within biofilm deposits. The following terms are used throughout this paper. Brief definitions are

Comparison of friction force between corroded and noncorroded titanium nitride plating of metal brackets.

PubMed

Kao, Chia-Tze; Guo, Jia-Uei; Huang, Tsui-Hsien

2011-05-01

Titanium nitride (TiN) plating is a method to prevent metal corrosion and can increase the surface smoothness. The purpose of this study was to evaluate the friction forces between the orthodontic bracket, with or without TiN plating, and stainless steel wire after it was corroded in fluoride-containing solution. In total, 540 metal brackets were divided into a control group and a TiN-coated experimental group. The electrochemical corrosion was performed in artificial saliva with 1.23% acidulated phosphate fluoride (APF) as the electrolytes. Static and kinetic friction were measured by an EZ-test machine (Shimadazu, Tokyo, Japan) with a crosshead speed of 10 mm per minute over a 5-mm stretch of stainless steel archwire. The data were analyzed by using unpaired t test and analysis of variance (ANOVA). Both the control and TiN-coated groups' corrosion potential was higher with 1.23% APF solution than with artificial solution (P <0.05). In brackets without corrosion, both the static and kinetic friction force between the control and TiN-coated brackets groups showed a statistically significant difference (P <0.05). In brackets with corrosion, the control group showed no statistical difference on kinetic or static friction. The TiN-coated brackets showed a statistical difference (P <0.05) on kinetic and static friction in different solutions. TiN-coated metal brackets, with corrosion or without corrosion, cannot reduce the frictional force. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Environmentally Friendly Anticorrosion Coating for High Strength Fasteners

DTIC Science & Technology

2011-01-01

phosphate Z24,zinc rich charcoal primer, black E-Coat. No red corrosion . Note: Cadmium controls were not included but expected to perform very well...also included as control . Several exposure environments were used including 500 hours B117 salt spray, 42 cycles GM9540P cyclic corrosion , and 1000...surface occurs, which limits corrosion . The potentiostat used here has an upper current density measurement of 1 x 10-3 A/cm2. Because the phosphate

Superheater Corrosion In Biomass Boilers: Today's Science and Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharp, William

2011-12-01

This report broadens a previous review of published literature on corrosion of recovery boiler superheater tube materials to consider the performance of candidate materials at temperatures near the deposit melting temperature in advanced boilers firing coal, wood-based fuels, and waste materials as well as in gas turbine environments. Discussions of corrosion mechanisms focus on the reactions in fly ash deposits and combustion gases that can give corrosive materials access to the surface of a superheater tube. Setting the steam temperature of a biomass boiler is a compromise between wasting fuel energy, risking pluggage that will shut the unit down, andmore » creating conditions that will cause rapid corrosion on the superheater tubes and replacement expenses. The most important corrosive species in biomass superheater corrosion are chlorine compounds and the most corrosion resistant alloys are typically FeCrNi alloys containing 20-28% Cr. Although most of these materials contain many other additional additions, there is no coherent theory of the alloying required to resist the combination of high temperature salt deposits and flue gases that are found in biomass boiler superheaters that may cause degradation of superheater tubes. After depletion of chromium by chromate formation or chromic acid volatilization exceeds a critical amount, the protective scale gives way to a thick layer of Fe{sub 2}O{sub 3} over an unprotective (FeCrNi){sub 3}O{sub 4} spinel. This oxide is not protective and can be penetrated by chlorine species that cause further acceleration of the corrosion rate by a mechanism called active oxidation. Active oxidation, cited as the cause of most biomass superheater corrosion under chloride ash deposits, does not occur in the absence of these alkali salts when the chloride is present as HCl gas. Although a deposit is more corrosive at temperatures where it is molten than at temperatures where it is frozen, increasing superheater tube temperatures through the measured first melting point of fly ash deposits does not necessarily produce a step increase in corrosion rate. Corrosion rate typically accelerates at temperatures below the first melting temperature and mixed deposits may have a broad melting temperature range. Although the environment at a superheater tube surface is initially that of the ash deposits, this chemistry typically changes as the deposits mature. The corrosion rate is controlled by the environment and temperature at the tube surface, which can only be measured indirectly. Some results are counter-intuitive. Two boiler manufacturers and a consortium have developed models to predict fouling and corrosion in biomass boilers in order to specify tube materials for particular operating conditions. It would be very useful to compare the predictions of these models regarding corrosion rates and recommended alloys in the boiler environments where field tests will be performed in the current program. Manufacturers of biomass boilers have concluded that it is more cost-effective to restrict steam temperatures, to co-fire biofuels with high sulfur fuels and/or to use fuel additives rather than try to increase fuel efficiency by operating with superheater tube temperatures above melting temperature of fly ash deposits. Similar strategies have been developed for coal fired and waste-fired boilers. Additives are primarily used to replace alkali metal chloride deposits with higher melting temperature and less corrosive alkali metal sulfate or alkali aluminum silicate deposits. Design modifications that have been shown to control superheater corrosion include adding a radiant pass (empty chamber) between the furnace and the superheater, installing cool tubes immediately upstream of the superheater to trap high chloride deposits, designing superheater banks for quick replacement, using an external superheater that burns a less corrosive biomass fuel, moving circulating fluidized bed (CFB) superheaters from the convective pass into the hot recirculated fluidizing medium and adding an insulating layer to superheater tubes to raise their surface temperature above the dew point temperature of alkali chlorides. These design changes offer advantages but introduce other challenges. For example, operating with superheater temperatures above the dew point of alkali chlorides could require the use of creep-resistant tube alloys and doesn't eliminate chloride corrosion. Improved test methods that can be applied within this project include automated dimensional metrology to make a statistical analysis of depth of penetration and corrosion product thickness, and simultaneous thermal analysis measurements to quantify the melting of complex ashes and avoid the unreliability of the standard ash fusion test. Other important developments in testing include the installation of individually-temperature-controlled superheater loops for corrosion testing in operating boilers and temperature gradient testing.« less

Corrosion initiation and propagation behavior of corrosion resistant concrete reinforcing materials

NASA Astrophysics Data System (ADS)

Hurley, Michael F.

The life of a concrete structure exposed to deicing compounds or seawater is often limited by chloride induced corrosion of the steel reinforcement. In this study, the key material attributes that affect the corrosion initiation and propagation periods were studied. These included material composition, surface condition, ageing time, propagation behavior during active corrosion, morphology of attack, and type of corrosion products generated by each rebar material. The threshold chloride concentrations for solid 316LN stainless steel, 316L stainless steel clad over carbon steel, 2101 LDX, MMFX-2, and carbon steel rebar were investigated using electrochemical techniques in saturated calcium hydroxide solutions. Surface preparation, test method, duration of period exposed to a passivating condition prior to introduction of chloride, and presence of cladding defects all affected the threshold chloride concentration obtained. A model was implemented to predict the extension of time until corrosion initiation would be expected. 8 years was the predicted time to corrosion initiation for carbon steel. However, model results confirmed that use of 316LN may increase the time until onset of corrosion to 100 years or more. To assess the potential benefits afforded by new corrosion resistant rebar alloys from a corrosion resistance standpoint the corrosion propagation behavior and other factors that might affect the risk of corrosion-induced concrete cracking must also be considered. Radial pit growth was found to be ohmically controlled but repassivation occurred more readily at high potentials in the case of 316LN and 2101 stainless steels. The discovery of ohmically controlled propagation enabled transformation of propagation rates from simulated concrete pore solution to less conductive concrete by accounting for resistance changes in the surrounding medium. The corrosion propagation behavior as well as the morphology of attack directly affects the propensity for concrete cracking. Experimental results were used in conjunction with an existing model to predict the time until concrete cracking occurs for new rebar materials. The results suggest that corrosion resistant materials offer a significant extension to the corrosion propagation stage over carbon steel, even in very aggressive conditions because small, localized anodes develop when initiated.

Corrosion of Continuous Fiber Reinforced Aluminum Metal Matrix Composites (CF-AMCs)

NASA Astrophysics Data System (ADS)

Tiwari, Shruti

The first objective of this research is to study the atmospheric corrosion behavior of continuous reinforced aluminum matrix composites (CF-AMCs). The materials used for this research were alumina (Al2O3) and nickel (Ni) coated carbon (C) fibers reinforced AMCs. The major focus is to identify the correlation between atmospheric parameters and the corrosion rates of CF-AMCs in the multitude of microclimates and environments in Hawai'i. The micro-structures of CF-AMCs were obtained to correlate the microstructures with their corrosion performances. Also electrochemical polarization experiments were conducted in the laboratory to explain the corrosion mechanism of CF-AMCs. In addition, CF-AMCs were exposed to seven different test sites for three exposure periods. The various climatic conditions like temperature (T), relative humidity (RH), rainfall (RF), time of wetness (TOW), chloride (Cl- ) and sulfate (SO42-) deposition rate, and pH were monitored for three exposure period. Likewise, mass losses of CF-AMCs at each test site for three exposure periods were determined. The microstructure of the CF-AMCS showed that Al/C/50f MMCs contained a Ni-rich phase in the matrix, indicating that the Ni coating on the C fiber dissolved in the matrix. The intermetallic phases obtained in Al-2wt% Cu/Al 2O3/50f-T6 MMC and Al-2wt%-T6 monolith were rich in Cu and Fe. The intermetallic phases obtained in Al 7075/Al2O3/50f-T6 MMC and Al 7075-T6 monolith also contained traces of Mg, Zn, Ni, and Si. Electrochemical polarization experiment indicated that the Al/Al 2O3/50f Al-2wt% Cu/Al2O3/50f-T6 and Al 7075/Al2O3/50f-T6 MMC showed similar corrosion trends as their respective monoliths pure Al, Al-2wt%-T6 and Al 7075-T6 in both aerated and deaerated condition. Al2O3 fiber, being an insulator, did not have a great effect on the polarization behavior of the composites. Al/C/50f MMCs corroded at a much faster rate as compared to pure Al monolith due to the galvanic effect between C and Al. According to the mass loss data of Al/C/50f MMCs, corrosion rate was high at marine environments (high Cl-) when compared to a tropical rainforest microclimate and low in a test site with a high SO2 and acid rain. Due to presence of conductive C fiber, the galvanic corrosion was a dominating corrosion mechanism. Due to high volume fraction of C, the corrosion phenomenon was cathodically controlled. The galvanic corrosion between C fiber and Al matrix showed a strong positive correlation with Cl - deposition rate. Lower corrosion rate at volcanic test site was attributed to dissolution of Ni rich phase, a potential cathodic site that promotes corrosion of Al/C/50f MMCs. Based on the mass loss data of Al2O3 based CF-AMCs and the monoliths showed maximum corrosion at volcanic test site when compared to any other test site. Due to the small volume fraction of intermetallic phases, the corrosion was anodically controlled. And hence the maximum anodic dissolution was found at volcanic test site (high SO2 and acid rain). The second objective of this thesis is to study the effect localized deformation on the corrosion of CF-AMCs. Corrosion initiation on Al (2 wt% Cu)/Al2O3/60f (60% fiber), Al 6061/Al2O 3/60f, and Al/Al2O3/60f CF-AMCs was studied in an aqueous environment The CF-AMCs and their monolithic alloys were deformed locally using a 1/16" diameter silicon nitride ball and 15-60 Kg load in a Rockwell hardness testing machine. Corrosion initiated at the deformed sites, and after longer exposures, spread over the entire region. Localized mechanical deformation resulted in micro-crevice formations at the fiber matrix interface. When deformed material is exposed to a corrosive solution, the crevices at the fiber matrix interface likely increased the hydrogen ion concentration lowering the pH at those regions, a process that leads to premature corrosion. The copper (Cu) rich CF-AMCs in aqueous solution resulted in dissolution of Cu rich phase and their subsequent deposition and redistribution as Cu over the deformed CF-AMCs surface. The corrosion rates of deformed CF-AMCs were higher than the non-deformed CF-AMCs.

Corrosion and mechanical performance of AZ91 exposed to simulated inflammatory conditions.

PubMed

Brooks, Emily K; Der, Stephanie; Ehrensberger, Mark T

2016-03-01

Magnesium (Mg) and its alloys, including Mg-9%Al-1%Zn (AZ91), are biodegradable metals with potential use as temporary orthopedic implants. Invasive orthopedic procedures can provoke an inflammatory response that produces hydrogen peroxide (H2O2) and an acidic environment near the implant. This study assessed the influence of inflammation on both the corrosion and mechanical properties of AZ91. The AZ91 samples in the inflammatory protocol were immersed for three days in a complex biologically relevant electrolyte (AMEM culture media) that contained serum proteins (FBS), 150 mM of H2O2, and was titrated to a pH of 5. The control protocol immersed AZ91 samples in the same biologically relevant electrolyte (AMEM & FBS) but without H2O2 and the acid titration. After 3 days all samples were switched into fresh AMEM & FBS for an additional 3-day immersion. During the initial immersion, inflammatory protocol samples showed increased corrosion rate determined by mass loss testing, increased Mg and Al ion released to solution, and a completely corroded surface morphology as compared to the control protocol. Although corrosion in both protocols slowed once the test electrolyte solution was replaced at 3 days, the samples originally exposed to the simulated inflammatory conditions continued to display enhanced corrosion rates as compared to the control protocol. These lingering effects may indicate the initial inflammatory corrosion processes modified components of the surface oxide and corrosion film or initiated aggressive localized processes that subsequently left the interface more vulnerable to continued enhanced corrosion. The electrochemical properties of the interfaces were also evaluated by EIS, which found that the corrosion characteristics of the AZ91 samples were potentially influenced by the role of intermediate adsorption layer processes. The increased corrosion observed for the inflammatory protocol did not affect the flexural mechanical properties of the AZ91 at any time point assessed. Copyright © 2015 Elsevier B.V. All rights reserved.

Influence of graphite-alloy interactions on corrosion of Ni-Mo-Cr alloy in molten fluorides

NASA Astrophysics Data System (ADS)

Ai, Hua; Hou, Juan; Ye, Xiang-Xi; Zeng, Chao Liu; Sun, Hua; Li, Xiaoyun; Yu, Guojun; Zhou, Xingtai; Wang, Jian-Qiang

2018-05-01

In this study, the effects of graphite-alloy interaction on corrosion of Ni-Mo-Cr alloy in molten FLiNaK salt were investigated. The corrosion tests of Ni-Mo-Cr alloys were conducted in graphite crucibles, to examine the differences of test specimens in conditions of electric contact and isolated with graphite, respectively. The corrosion attack is severer with more weight loss and deeper Cr depletion layer in samples electric contact with graphite than those isolated with graphite. The occurrence of galvanic corrosion between alloy specimens and graphite container was confirmed by electrochemical measurement. The corrosion is controlled by nonelectric transfer in isolated test while electrochemical reaction accelerated corrosion in electric contact test.

SRB seawater corrosion project

NASA Technical Reports Server (NTRS)

Bozack, M. J.

1991-01-01

The corrosion behavior of 2219 aluminum when exposed to seawater was characterized. Controlled corrosion experiments at three different temperatures (30, 60 and 100 C) and two different environments (seawater and 3.5 percent salt solution) were designed to elucidate the initial stages in the corrosion process. It was found that 2219 aluminum is an active catalytic surface for growth of Al2O3, NaCl, and MgO. Formation of Al2O3 is favored at lower temperatures, while MgO is favored at higher temperatures. Visible corrosion products are formed within 30 minutes after seawater exposure. Corrosion characteristics in 3.5 percent salt solution are different than corrosion in seawater. Techniques utilized were: (1) scanning electron microscopy, (2) energy dispersive x-ray spectroscopy, and (3) Auger electron spectroscopy.

Review and study of physics driven pitting corrosion modeling in 2024-T3 aluminum alloys

NASA Astrophysics Data System (ADS)

Yu, Lingyu; Jata, Kumar V.

2015-04-01

Material degradation due to corrosion and corrosion fatigue has been recognized to significantly affect the airworthiness of civilian and military aircraft, especially for the current fleet of airplanes that have served beyond their initial design life. The ability to predict the corrosion damage development in aircraft components and structures, therefore, is of great importance in managing timely maintenance for the aging aircraft vehicles and in assisting the design of new ones. The assessment of aircraft corrosion and its influence on fatigue life relies on appropriate quantitative models that can evaluate the initiation of the corrosion as well as the accumulation during the period of operation. Beyond the aircraft regime, corrosion has also affected the maintenance, safety and reliability of other systems such as nuclear power systems, steam and gas turbines, marine structures and so on. In the work presented in this paper, we reviewed and studied several physics based pitting corrosion models that have been reported in the literature. The classic work of particle induced pitting corrosion by Wei and Harlow is reviewed in detail. Two types of modeling, a power law based simplified model and a microstructure based model, are compared for 2024-T3 alloy. Data from literatures are used as model inputs. The paper ends with conclusions and recommendations for future work.

A SIMPLE APPROACH TO ASSESSING COPPER PITTING CORROSION TENDENCIES AND DEVELOPING CONTROL STRATEGIES

EPA Science Inventory

Localized corrosion of copper premise plumbing in drinking water distribution systems can lead to pinhole leaks, which are a growing problem for many homeowners. Despite the fact that water quality is an important factor associated with localized copper corrosion, definitive appr...

49 CFR 192.485 - Remedial measures: Transmission lines.

Code of Federal Regulations, 2011 CFR

2011-10-01

... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.485 Remedial measures: Transmission lines. (a) General corrosion. Each segment of transmission line with general corrosion and with a remaining wall thickness less than that required for the...

Corrosion Engineering.

ERIC Educational Resources Information Center

White, Charles V.

A description is provided for a Corrosion and Corrosion Control course offered in the Continuing Engineering Education Program at the General Motors Institute (GMI). GMI is a small cooperative engineering school of approximately 2,000 students who alternate between six-week periods of academic study and six weeks of related work experience in…

49 CFR 192.485 - Remedial measures: Transmission lines.

Code of Federal Regulations, 2012 CFR

2012-10-01

... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.485 Remedial measures: Transmission lines. (a) General corrosion. Each segment of transmission line with general corrosion and with a remaining wall thickness less than that required for the...

49 CFR 192.485 - Remedial measures: Transmission lines.

Code of Federal Regulations, 2014 CFR

2014-10-01

... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.485 Remedial measures: Transmission lines. (a) General corrosion. Each segment of transmission line with general corrosion and with a remaining wall thickness less than that required for the...

49 CFR 192.485 - Remedial measures: Transmission lines.

Code of Federal Regulations, 2013 CFR

2013-10-01

... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.485 Remedial measures: Transmission lines. (a) General corrosion. Each segment of transmission line with general corrosion and with a remaining wall thickness less than that required for the...

THE CORROSION CONTROL-WATER QUALITY SPIDER WEB

EPA Science Inventory

This presentation provides an overview of new research results and emerging research needs with respect to both corrosion control issues, (lead, copper, iron) and to issues of inorganic contaminants that can form or accumulate in distribution system, water, pipe scales and distri...

Do Stem Taper Microgrooves Influence Taper Corrosion in Total Hip Arthroplasty? A Matched Cohort Retrieval Study.

PubMed

Arnholt, Christina M; MacDonald, Daniel W; Underwood, Richard J; Guyer, Eric P; Rimnac, Clare M; Kurtz, Steven M; Mont, Michael A; Klein, Gregg R; Lee, Gwo-Chin; Chen, Antonia F; Hamlin, Brian R; Cates, Harold E; Malkani, Arthur L; Kraay, Matthew J

2017-04-01

Previous studies identified imprinting of the stem morphology onto the interior head bore, leading researchers to hypothesize an influence of taper topography on mechanically assisted crevice corrosion. The purpose of this study was to analyze whether microgrooved stem tapers result in greater fretting corrosion damage than smooth stem tapers. A matched cohort of 120 retrieved head-stem pairs from metal-on-polyethylene bearings was created controlling for implantation time, flexural rigidity, apparent length of engagement, and head size. There were 2 groups of 60 heads each, mated with either smooth or microgrooved stem tapers. A high-precision roundness machine was used to measure and categorize the surface morphology. Fretting corrosion damage at the head-neck junction was characterized using the Higgs-Goldberg scoring method. Fourteen of the most damaged heads were analyzed for the maximum depth of material loss and focused ion beam cross-sectioned to view oxide and base metal. Fretting corrosion damage was not different between the 2 cohorts at the femoral head (P = .14, Mann-Whitney) or stem tapers (P = .35). There was no difference in the maximum depths of material loss between the cohorts (P = .71). Cross-sectioning revealed contact damage, signs of micro-motion, and chromium-rich oxide layers in both cohorts. Microgroove imprinting did not appear to have a different effect on the fretting corrosion behavior. The results of this matched cohort retrieval study do not support the hypothesis that taper surfaces with microgrooved stems exhibit increased in vivo fretting corrosion damage or material release. Copyright © 2016 Elsevier Inc. All rights reserved.

Corrosion-induced microstructural developments in 316 stainless steel during exposure to molten Li 2BeF 4(FLiBe) salt

DOE PAGES

Zheng, Guiqiu; He, Lingfeng; Carpenter, David; ...

2016-10-12

The microstructural evaluation and characterization of 316 stainless steel samples that were tested in molten Li 2BeF 4 (FLiBe) salt were investigated in this study for evaluating its performance in high-temperature molten fluoride salts. Recently, 316 stainless steel and FLiBe salt are being actively considered as the main structural alloy and primary coolant of fluoride salt-cooled high-temperature reactor (FHR), a leading nuclear reactor concept for the next generation nuclear plants (NGNP). In support of the materials development for the FHR, high-temperature corrosion tests of 316 stainless steel in molten FLiBe salt at 700°C have been conducted in both bare graphitemore » crucibles and 316 stainless steel-lined crucibles in an inert atmosphere for up to 3000 hours. The microstructure of the tested samples was comprehensively characterized using scanning electron microscopy (SEM) in conjunction with energy dispersive x-ray spectroscopy (EDS) and electron backscatter diffraction (EBSD), and scanning transmission electron microscopy (STEM) with EDS. In addition to the noticeable intergranular corrosion attack on surface, the corrosion in terms of the Cr depletion along high angle grain boundaries (15-180º) extended to 22µm in depth after 3000-hour exposure to molten FLiBe salt in graphite crucible. The coherent Σ3 grain boundary appeared high resistance to the Cr depletion. The substantial Cr depletion from the near-to-surface layer induced phase transformation from γ-martensite to α-ferrite phase (FeNi x) during corrosion at 700ºC. Furthermore, the presence of graphite in the molten salt doubled the corrosion attack depth and led to the formation of round Mo2C, hexagonal Cr 7C 3 and needle-like Al 4C 3 phase within the alloy as deep as 50 µm after 3000-hour corrosion testing. Based on the microstructural analysis, the corrosion mechanisms of 316 stainless steel in molten FLiBe salt in different corrosion crucibles were illuminated through schematic diagrams. Additionally, a thermal diffusion controlled corrosion model was developed and validated by experimental data for predicting the long-term corrosion attack depth.« less

Corrosion-induced microstructural developments in 316 stainless steel during exposure to molten Li 2BeF 4(FLiBe) salt

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Guiqiu; He, Lingfeng; Carpenter, David

The microstructural evaluation and characterization of 316 stainless steel samples that were tested in molten Li 2BeF 4 (FLiBe) salt were investigated in this study for evaluating its performance in high-temperature molten fluoride salts. Recently, 316 stainless steel and FLiBe salt are being actively considered as the main structural alloy and primary coolant of fluoride salt-cooled high-temperature reactor (FHR), a leading nuclear reactor concept for the next generation nuclear plants (NGNP). In support of the materials development for the FHR, high-temperature corrosion tests of 316 stainless steel in molten FLiBe salt at 700°C have been conducted in both bare graphitemore » crucibles and 316 stainless steel-lined crucibles in an inert atmosphere for up to 3000 hours. The microstructure of the tested samples was comprehensively characterized using scanning electron microscopy (SEM) in conjunction with energy dispersive x-ray spectroscopy (EDS) and electron backscatter diffraction (EBSD), and scanning transmission electron microscopy (STEM) with EDS. In addition to the noticeable intergranular corrosion attack on surface, the corrosion in terms of the Cr depletion along high angle grain boundaries (15-180º) extended to 22µm in depth after 3000-hour exposure to molten FLiBe salt in graphite crucible. The coherent Σ3 grain boundary appeared high resistance to the Cr depletion. The substantial Cr depletion from the near-to-surface layer induced phase transformation from γ-martensite to α-ferrite phase (FeNi x) during corrosion at 700ºC. Furthermore, the presence of graphite in the molten salt doubled the corrosion attack depth and led to the formation of round Mo2C, hexagonal Cr 7C 3 and needle-like Al 4C 3 phase within the alloy as deep as 50 µm after 3000-hour corrosion testing. Based on the microstructural analysis, the corrosion mechanisms of 316 stainless steel in molten FLiBe salt in different corrosion crucibles were illuminated through schematic diagrams. Additionally, a thermal diffusion controlled corrosion model was developed and validated by experimental data for predicting the long-term corrosion attack depth.« less

Corrosion control acceptance criteria for sacrificial anode type, cathodic protection systems (user guide)

NASA Astrophysics Data System (ADS)

Hock, Vincent F.; Noble, Michael; McLeod, Malcolm E.

1994-07-01

The Army currently operates and maintains more than 20,000 underground storage tanks and over 3000 miles of underground gas pipelines, all of which require some form of corrosion control. Cathodic protection is one method of corrosion control used to prevent corrosion-induced leaks when a steel structure is exposed to an aggressive soil. The corrosion control acceptance criteria for sacrificial anode type CP systems provides guidelines for the DEH/DPW cathodic protection installation inspectors whose responsibilities are to ensure that the materials and equipment specified are delivered to the job site and subsequently installed in accordance with the engineering drawings and specifications. The sacrificial anode CP acceptance criteria includes all components for the sacrificial anode system such as insulated conductors, anodes, anode backfills, and auxiliary equipment. The sacrificial anode CP acceptance criteria is composed of a checklist that lists each component and that contains a space for the inspector to either check 'yes' or 'no' to indicate whether the component complies with the job specifications. In some cases, the inspector must measure and record physical dimensions or electrical output and compare the measurements to standards shown in attached tables.

Metallized coatings for corrosion control of Naval ship structures and components

NASA Technical Reports Server (NTRS)

1983-01-01

In attempting to improve corrosion control, the U.S. Navy has undertaken a program of coating corrosion-susceptible shipboard components with thermally sprayed aluminum. In this report the program is reviewed in depth, including examination of processes, process controls, the nature and properties of the coatings, nondestructive examination, and possible hazards to personnel. The performance of alternative metallic coating materials is also discussed. It is concluded that thermally sprayed aluminum can provide effective long-term protection against corrosion, thereby obviating the need for chipping of rust and repainting by ship personnel. Such coatings are providing excellent protection to below-deck components such as steam valves, but improvements are needed to realize the full potential of coatings for above-deck service. Several recommendations are made regarding processes, materials, and research and development aimed at upgrading further the performance of these coatings.

Corrosion Behavior of Titanium Grade 7 in Fluoride-Containing NaCl Brines

DOE Office of Scientific and Technical Information (OSTI.GOV)

NA

2004-05-18

Titanium Grade 7 (UNS R52400) is a titanium-based alloy with 0.12-0.25% Pd. The addition of the small amount of palladium is to ennoble the corrosion potential of Ti, thus improving the corrosion resistance of titanium in reducing environments. In most aqueous environments, Ti and Ti alloys demonstrate excellent corrosion resistance due to the protective oxide film that forms spontaneously and remains stable on the surface. However, Ti and Ti alloys are susceptible to corrosion in fluoride-containing environments due to the formation of complexes such as TiF{sub 6}{sup 2-} and TiF{sub 6}{sup 3-}, which are stable and soluble in electrolyte solutions.more » Without the presence of fluoride, only slight effects from [Cl{sup -}], pH and temperature have been reported [1]. It has been reported that the kinetics of passive corrosion of titanium in neutral solutions and controlled by the migration of the defects in the oxide across the surface film [2]. Thus, the increase in thickness and improvement in film properties, by thermal oxidation, would lead to a significant decrease in the susceptibility to film breakdown and in the passive corrosion rate. This report summarizes recent experiment results in studies of the environmental influence on the corrosion behavior of Titanium Grade 7 (Ti-7) in NaCl brines containing fluoride. The environmental factors to be studied include temperature, pH, chloride and fluoride concentration. This report also includes the effects of oxide film, formed during an anneal treatment, on the corrosion behavior of Ti-7. Polarization measurement techniques including potentiodynamic and potentiostatic scans were use3d to characterize corrosion kinetics and susceptibility. Due to the unique alloying in Titanium Grade 7, the long-term corrosion behavior is heavily influenced by the surface enrichment of Pd. Use of electrochemical impedance spectroscopy in conjunction with a potentiostatic scan will reveal the transformation in the corrosion behavior as a function of Pd enrichment on the metal surface. Surface characterization was done using various analytical techniques including X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), and scanning electron microscopy (SEM). The effect of fluoride ion on the corrosion behavior of Ti-7 is strongly dependent on the solution pH. In neutral (pH 8) and alkaline (pH 11) solutions, fluoride did not affect the corrosion rate significantly even though it altered the anodic polarization curve drastically. With pH decreased to 4, the corrosion rate of Ti-7 was increased significantly by the presence of fluoride.« less

Self-immunity microcapsules for corrosion protection of steel bar in reinforced concrete

NASA Astrophysics Data System (ADS)

Wang, Yanshuai; Fang, Guohao; Ding, Weijian; Han, Ningxu; Xing, Feng; Dong, Biqin

2015-12-01

A novel microcapsule-based self-immunity system for reinforced concrete is proposed. Its feasibility for hindering the corrosion of steel rebar by means of lifting the threshold value of [Cl-]/[OH-] is discussed. Precisely controlled release behavior enables corrosion protection in the case of depassivation. The release process is characterized over a designated range of pH values, and its release characteristics of the microcapsules, triggered by decreasing pH value, are captured by observing that the core crystals are released when exposed to a signal (stimulus). The aim of corrosion protection of steel bar is achieved through the constantly-stabilized passive film, and its stability is promoted using continuous calcium hydroxide released from the microcapsule, restoring alkaline conditions. The test results exhibited that the release process of the microcapsules is a function of time. Moreover, the release rate of core materials could interact with environmental pH value, in which the release rate is found to increase remarkably with decreasing pH value, but is inhibited by high pH levels.

Self-immunity microcapsules for corrosion protection of steel bar in reinforced concrete.

PubMed

Wang, Yanshuai; Fang, Guohao; Ding, Weijian; Han, Ningxu; Xing, Feng; Dong, Biqin

2015-12-17

A novel microcapsule-based self-immunity system for reinforced concrete is proposed. Its feasibility for hindering the corrosion of steel rebar by means of lifting the threshold value of [Cl(-)]/[OH(-)] is discussed. Precisely controlled release behavior enables corrosion protection in the case of depassivation. The release process is characterized over a designated range of pH values, and its release characteristics of the microcapsules, triggered by decreasing pH value, are captured by observing that the core crystals are released when exposed to a signal (stimulus). The aim of corrosion protection of steel bar is achieved through the constantly-stabilized passive film, and its stability is promoted using continuous calcium hydroxide released from the microcapsule, restoring alkaline conditions. The test results exhibited that the release process of the microcapsules is a function of time. Moreover, the release rate of core materials could interact with environmental pH value, in which the release rate is found to increase remarkably with decreasing pH value, but is inhibited by high pH levels.

Fatigue and fluoride corrosion on Streptococcus mutans adherence to titanium-based implant/component surfaces.

PubMed

Correa, Cassia Bellotto; Pires, Juliana Rico; Fernandes-Filho, Romeu Belon; Sartori, Rafael; Vaz, Luis Geraldo

2009-07-01

The influence of fatigue and the fluoride ion corrosion process on Streptococcus mutans adherence to commercially pure Titanium (Cp Ti) implant/component set surfaces were studied. Thirty Nobel implants and 30 Neodent implants were used. Each commercial brand was divided into three groups. Group A: control, Group B: sets submitted to fatigue (10(5) cycles, 15 Hz, 150 N), and Group C: sets submitted to fluoride (1500 ppm, pH 5.5) and fatigue, simulating a mean use of 5 years in the oral medium. Afterward, the sets were contaminated with standard strains of S. mutans (NTCC 1023) and analyzed by scanning electronic microscopy (SEM) and colony-forming unit counts (CFU/mL). By SEM, bacterial adherence was verified only in group C in both brands. By CFU/mL counts, S. mutans was statistically higher in both brands in group C than in groups A and B (p < 0.05, ANOVA). The process of corrosion by fluoride ions on Cp Ti implant/component sets allowed greater S. mutans adherence than in the absence of corrosion and with the fatigue process in isolation.

Investigation on corrosion behavior of Ni-based alloys in molten fluoride salt using synchrotron radiation techniques

NASA Astrophysics Data System (ADS)

Liu, Min; Zheng, Junyi; Lu, Yanling; Li, Zhijun; Zou, Yang; Yu, Xiaohan; Zhou, Xingtai

2013-09-01

Ni-based alloys have been selected as the structural materials in molten-salt reactors due to their high corrosion resistance and excellent mechanical properties. In this paper, the corrosion behavior of some Ni-based superalloys including Inconel 600, Hastelloy X and Hastelloy C-276 were investigated in molten fluoride salts at 750 °C. Morphology and microstructure of corroded samples were analyzed using scanning electron microscope (SEM), synchrotron radiation X-ray microbeam fluorescence (μ-XRF) and synchrotron radiation X-ray diffraction (SR-XRD) techniques. Results from μ-XRF and SR-XRD show that the main depleted alloying element of Ni-based alloys in molten fluoride salt is Cr. In addition, the results indicate that Mo can enhance the corrosion resistance in molten FLiNaK salts. Among the above three Ni-based alloys, Hastelloy C-276 exhibits the best corrosion resistance in molten fluoride salts 750 °C. Higher-content Mo and lower-content Cr in Hastelloy C-276 alloy were responsible for the better anti-corrosive performance, compared to the other two alloys.

Efforts to reduce exposure at Japanese PWRs: CVCS improvement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terada, Ryosuke

1995-03-01

Many reports have been focused on the reduction of radiation sources and related occupational exposures. The radiation sources mainly consist of corrosion products. Radiation dose rate is determined by the amount of the activated corrosion products on the surface of the primary loop components of Pressurized Water Reactor (PWR) plants. Therefore, reducing the amount of the corrosion product will contribute to the reduction of occupational exposures. In order to reduce the corrosion products, Chemical and Volume Control System (CVCS) has been improved in Japanese PWRs as follows: (a) Cation Bed Demineralizer Flowrate Control; (b) Hydrogen Peroxide Injection System; (c) Purificationmore » Flowrate During Plant Shutdown; (d) Fine Mesh Filters Upstream of Mixed Bed Demineralizers.« less

Biodegradable magnesium alloys for orthopaedic applications: A review on corrosion, biocompatibility and surface modifications.

PubMed

Agarwal, Sankalp; Curtin, James; Duffy, Brendan; Jaiswal, Swarna

2016-11-01

Magnesium (Mg) and its alloys have been extensively explored as potential biodegradable implant materials for orthopaedic applications (e.g. Fracture fixation). However, the rapid corrosion of Mg based alloys in physiological conditions has delayed their introduction for therapeutic applications to date. The present review focuses on corrosion, biocompatibility and surface modifications of biodegradable Mg alloys for orthopaedic applications. Initially, the corrosion behaviour of Mg alloys and the effect of alloying elements on corrosion and biocompatibility is discussed. Furthermore, the influence of polymeric deposit coatings, namely sol-gel, synthetic aliphatic polyesters and natural polymers on corrosion and biological performance of Mg and its alloy for orthopaedic applications are presented. It was found that inclusion of alloying elements such as Al, Mn, Ca, Zn and rare earth elements provides improved corrosion resistance to Mg alloys. It has been also observed that sol-gel and synthetic aliphatic polyesters based coatings exhibit improved corrosion resistance as compared to natural polymers, which has higher biocompatibility due to their biomimetic nature. It is concluded that, surface modification is a promising approach to improve the performance of Mg-based biomaterials for orthopaedic applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Surface modification of a biodegradable magnesium alloy with phosphorylcholine (PC) and sulfobetaine (SB) functional macromolecules for reduced thrombogenicity and acute corrosion resistance

PubMed Central

Ye, Sang-Ho; Jang, Yong-Seok; Yun, Yeo-Heung; Shankarraman, Venkat; Woolley, Joshua R.; Hong, Yi; Gamble, Lara J.; Ishihara, Kazuhiko; Wagner, William R.

2013-01-01

Siloxane functionalized phosphorylcholine (PC) or sulfobetaine (SB) macromolecules (PCSSi or SBSSi) were synthesized to act as surface modifying agents for degradable metallic surfaces to improve acute blood compatibility and slow initial corrosion rates. The macromolecules were synthesized using a thiol-ene radical photopolymerization technique and then utilized to modify magnesium (Mg) alloy (AZ31) surfaces via an anhydrous phase deposition of the silane functional groups. X-ray photoelectron spectroscopy surface analysis results indicated successful surface modification based on increased nitrogen and phosphorus or sulfur composition on the modified surfaces relative to unmodified AZ31. In vitro acute thrombogenicity assessment after ovine blood contact with the PCSSi and SBSSi modified surfaces showed a significant decrease in platelet deposition and bulk phase platelet activation compared with the control alloy surfaces. Potentiodynamic polarization and electrochemical impedance spectroscopy data obtained from electrochemical corrosion testing demonstrated increased corrosion resistance for PCSSi and SBSSi modified AZ31 versus unmodified surfaces. The developed coating technique using PCSSi or SBSSi showed promise in acutely reducing both the corrosion and thrombotic processes, which would be attractive for application to blood contacting devices, such as vascular stents, made from degradable Mg alloys. PMID:23705967

A SIMPLE APPROACH TO ASSESSING COPPER PITTING CORROSION TENDENCIES AND DEVELOPING CONTROL STRATEGIES

EPA Science Inventory

Localized corrosion of copper plumbing in drinking water distribution systems can lead to pinhole leaks, which are a growing problem for many homeowners. Although water quality is one factor that can be responsible for localized copper corrosion, there is not a good approach to ...

The Impact of Hexametaphosphate, Orthophosphate, and Temperature on Copper Corrosion and Release

EPA Science Inventory

Excessive corrosion of copper plumbing can lead to elevated copper levels at consumer’s tap or pinhole leaks. Corrosion control solutions include pH adjustment or phosphate addition. Orthophosphate has been shown to reduce copper levels in some cases while the role of polyphosp...

Corrosion Behavior and Strength of Dissimilar Bonding Material between Ti and Mg Alloys Fabricated by Spark Plasma Sintering

PubMed Central

Pripanapong, Patchara; Kariya, Shota; Luangvaranunt, Tachai; Umeda, Junko; Tsutsumi, Seiichiro; Takahashi, Makoto; Kondoh, Katsuyoshi

2016-01-01

Ti and solution treated Mg alloys such as AZ31B (ST), AZ61 (ST), AZ80 (ST) and AZ91 (ST) were successfully bonded at 475 °C by spark plasma sintering, which is a promising new method in welding field. The formation of Ti3Al intermetallic compound was found to be an important factor in controlling the bonding strength and galvanic corrosion resistance of dissimilar materials. The maximum bonding strength and bonding efficiency at 193 MPa and 96% were obtained from Ti/AZ91 (ST), in which a thick and uniform nano-level Ti3Al layer was observed. This sample also shows the highest galvanic corrosion resistance with a measured galvanic width and depth of 281 and 19 µm, respectively. The corrosion resistance of the matrix on Mg alloy side was controlled by its Al content. AZ91 (ST) exhibited the highest corrosion resistance considered from its corrode surface after corrosion test in Kroll’s etchant. The effect of Al content in Mg alloy on bonding strength and corrosion behavior of Ti/Mg alloy (ST) dissimilar materials is discussed in this work. PMID:28773788

SILICATES FOR CORROSION CONTROL IN BUILDING POTABLE WATER SYSTEMS

EPA Science Inventory

Silicates have been used to control the corrosion of drinking water distribution system materials. Previous work has shown that they are particularly useful in reducing the release of zinc from galvanized materials in hot water systems. Negatively charged silicate species were re...

49 CFR 195.575 - Which facilities must I electrically isolate and what inspections, tests, and safeguards are...

Code of Federal Regulations, 2010 CFR

2010-10-01

... Corrosion Control § 195.575 Which facilities must I electrically isolate and what inspections, tests, and... isolation of a portion of a pipeline is necessary to facilitate the application of corrosion control. (c...

CORROSION CONTROL: IT'S NOT JUST GETTING THE LEAD OUT

EPA Science Inventory

This presentation will focus on the three corrosion control strategies applied in New England including: pH adjustment alone, pH adjustment with carbonate alkalinity supplementation, and pH adjustment with phosphate addition. The consequences of these changes will be discussed in...

49 CFR 193.2707 - Operations and maintenance.

Code of Federal Regulations, 2010 CFR

2010-10-01

.... (c) Corrosion control procedures under § 193.2605(b), including those for the design, installation, operation, and maintenance of cathodic protection systems, must be carried out by, or under the direction of, a person qualified by experience and training in corrosion control technology. ...

49 CFR 193.2707 - Operations and maintenance.

Code of Federal Regulations, 2011 CFR

2011-10-01

.... (c) Corrosion control procedures under § 193.2605(b), including those for the design, installation, operation, and maintenance of cathodic protection systems, must be carried out by, or under the direction of, a person qualified by experience and training in corrosion control technology. ...

49 CFR 193.2631 - Internal corrosion control.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Internal corrosion control. 193.2631 Section 193.2631 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS...

49 CFR 193.2631 - Internal corrosion control.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Internal corrosion control. 193.2631 Section 193.2631 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS...

49 CFR 193.2631 - Internal corrosion control.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Internal corrosion control. 193.2631 Section 193.2631 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS...

Memo Addressing Lead and Copper Rule Requirements for Optimal Corrosion Control Treatment

EPA Pesticide Factsheets

EPA has recently published a memo to address the requirements pertaining to maintenance of optimal corrosion control treatment, in situations in which a large water system ceases to purchase treated water and switches to a new drinking water source.

49 CFR 192.467 - External corrosion control: Electrical isolation.

Code of Federal Regulations, 2013 CFR

2013-10-01

... submerged pipeline must be electrically isolated from other underground metallic structures, unless the pipeline and the other structures are electrically interconnected and cathodically protected as a single... pipeline is necessary to facilitate the application of corrosion control. (c) Except for unprotected copper...

49 CFR 192.467 - External corrosion control: Electrical isolation.

Code of Federal Regulations, 2014 CFR

2014-10-01

... submerged pipeline must be electrically isolated from other underground metallic structures, unless the pipeline and the other structures are electrically interconnected and cathodically protected as a single... pipeline is necessary to facilitate the application of corrosion control. (c) Except for unprotected copper...

49 CFR 192.467 - External corrosion control: Electrical isolation.

Code of Federal Regulations, 2012 CFR

2012-10-01

... submerged pipeline must be electrically isolated from other underground metallic structures, unless the pipeline and the other structures are electrically interconnected and cathodically protected as a single... pipeline is necessary to facilitate the application of corrosion control. (c) Except for unprotected copper...

Corrosion resistance of new beta type titanium alloy, Ti-29Nb-13Ta-4.6Zr in artificial saliva solution

NASA Astrophysics Data System (ADS)

Gunawarman; Giatmana, D. D.; Ilhamdi; Affi, J.; Fonna, S.; Niinomi, M.; Nakai, M.

2018-05-01

The corrosion resistance of Ti-29Nb-13Ta-4.6Zr (TNTZ) and Ti-6Al-4V alloys in oral cavity environment were studied by investigating its corrosion rate in artificial saliva solution. Corrosion measurement was conducted in 600 ml solution of Fusayama-Meyer artificial saliva containing 0.4g NaCl, 0.4g KCl, 0.795g CaCl2.2H2O, 0.69g NaH2PO4, and 1 g urea using a potentiostat controlled by a personal computer. The solution was maintained at pH 5.2 and controlled the temperature of 37°C to imitate oral cavity condition. After corrosion test, specimen surfaces were examined by SEM and EDX. The results show that the average corrosion rate of TNTZ and Ti-6Al-4V is 4,5×10-9 mmy-1 and 6,4×10-8 mmy-1, respectively, indicating that the corrosion resistance of TNTZ is slightly better than Ti-6Al-4V. This is suggested mainly due to the formation of multiple layers of Ti, Nb and Zr oxides in the surface of TNTZ. However, the formation of micro-pitting corrosion is more severe in TNTZ as compared to that of Ti-6Al-4V. The intense pitting corrosion in TNTZ is found strongly corresponded to its high impurities content and wide elemental segregation. It is recommended, therefore, a longer homogenizing process is required in TNTZ for reducing pitting corrosion attack. However, the details of corrosion mechanism are needed to be explored further.

Vapor Corrosion Response of Low Carbon Steel Exposed to Simulated High Level Radioactive Waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiersma, B

2006-01-26

A program to resolve the issues associated with potential vapor space corrosion and liquid/air interface corrosion in the Type III high level waste tanks is in place. The objective of the program is to develop understanding of vapor space (VSC) and liquid/air interface (LAIC) corrosion to ensure a defensible technical basis to provide accurate corrosion evaluations with regard to vapor space and liquid/air interface corrosion. The results of the FY05 experiments are presented here. The experiments are an extension of the previous research on the corrosion of tank steel exposed to simple solutions to corrosion of the steel when exposedmore » to complex high level waste simulants. The testing suggested that decanting and the consequent residual species on the tank wall is the predominant source of surface chemistry on the tank wall. The laboratory testing has shown that at the boundary conditions of the chemistry control program for solutions greater than 1M NaNO{sub 3}{sup -}. Minor and isolated pitting is possible within crevices in the vapor space of the tanks that contain stagnant dilute solution for an extended period of time, specifically when residues are left on the tank wall during decanting. Liquid/air interfacial corrosion is possible in dilute stagnant solutions, particularly with high concentrations of chloride. The experimental results indicate that Tank 50 would be most susceptible to the potential for liquid/air interfacial corrosion or vapor space corrosion, with Tank 49 and 41 following, since these tanks are nearest to the chemistry control boundary conditions. The testing continues to show that the combination of well-inhibited solutions and mill-scale sufficiently protect against pitting in the Type III tanks.« less

The Corrosion Behavior of Ni3(Si,Nb) Alloys in Boiling 70 wt.% Sulfuric Acid

NASA Astrophysics Data System (ADS)

Hsu, Jen-Hsien; Larson, Christopher M.; Newkirk, Joseph W.; Brow, Richard K.; Zhang, San-Hong

2016-02-01

Corrosion-resistant Ni3(Si,Nb) alloys are promising materials of construction for hydrogen-production systems based on the sulfur-iodine thermochemical cycle. In this work, the corrosion rates of three different Ni3(Si,Nb) alloys were measured in boiling 70 wt.% sulfuric acid and a three-stage corrosion mechanism was identified, based on the composition and morphology of surface scale that developed. The α(Ni) + β(Ni3Si) eutectic constituent of the alloy microstructure was selectively attacked by acid and, when present, is detrimental to corrosion resistance. The G-phase (Ni16Si17Nb6) is more passive than the β-matrix and seems to contribute to a lower steady-state corrosion rate.

Effect of Chromate and Chromate-Free Organic Coatings on Corrosion Fatigue of an Aluminum Alloy

DTIC Science & Technology

2012-02-20

Investigations of alloy AA7075 corrosion in acid rain solution, inhibited by chromate-free blends of zinc phosphate with bentonite, zeolite and calcium...with solution components. Single use of zinc phosphate and these ion exchanged pigments for corrosion inhibition do not provide desired effect...primer performance against corrosion fatigue cracking under a commercial polyurethane topcoat. As a control , they used samples of chromated AA2024

Thermally oxidized titania nanotubes enhance the corrosion resistance of Ti6Al4V.

PubMed

Grotberg, John; Hamlekhan, Azhang; Butt, Arman; Patel, Sweetu; Royhman, Dmitry; Shokuhfar, Tolou; Sukotjo, Cortino; Takoudis, Christos; Mathew, Mathew T

2016-02-01

The negative impact of in vivo corrosion of metallic biomedical implants remains a complex problem in the medical field. We aimed to determine the effects of electrochemical anodization (60V, 2h) and thermal oxidation (600°C) on the corrosive behavior of Ti-6Al-4V, with serum proteins, at physiological temperature. Anodization produced a mixture of anatase and amorphous TiO2 nanopores and nanotubes, while the annealing process yielded an anatase/rutile mixture of TiO2 nanopores and nanotubes. The surface area was analyzed by the Brunauer-Emmett-Teller method and was estimated to be 3 orders of magnitude higher than that of polished control samples. Corrosion resistance was evaluated on the parameters of open circuit potential, corrosion potential, corrosion current density, passivation current density, polarization resistance and equivalent circuit modeling. Samples both anodized and thermally oxidized exhibited shifts of open circuit potential and corrosion potential in the noble direction, indicating a more stable nanoporous/nanotube layer, as well as lower corrosion current densities and passivation current densities than the smooth control. They also showed increased polarization resistance and diffusion limited charge transfer within the bulk oxide layer. The treatment groups studied can be ordered from greatest corrosion resistance to least as Anodized+Thermally Oxidized > Anodized > Smooth > Thermally Oxidized for the conditions investigated. This study concludes that anodized surface has a potential to prevent long term implant failure due to corrosion in a complex in-vivo environment. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of Ca(OH)2, NaCl, and Na2SO4 on the corrosion and electrochemical behavior of rebar

NASA Astrophysics Data System (ADS)

Jin, Zuquan; Zhao, Xia; Zhao, Tiejun; Hou, Baorong; Liu, Ying

2017-05-01

The corrosion of rebar in reinforced concrete in marine environments causes significant damage to structures built in ocean environments. Studies on the process and mechanism of corrosion of rebar in the presence of multiple ions may help to control damage and predict the service life of reinforced concrete structures in such environments. The effect of interactions between sulfate and chloride ions and calcium hydroxide on the electrochemical behavior of rebar are also important for evaluation of structure durability. In this work, electrochemical impedance spectroscopy (EIS) plots of rebar in Ca(OH)2 solution and cement grout, including NaCl and Na2SO4 as aggressive salts, were measured for diff erent immersion times. The results show that corrosion of rebar was controlled by the rate of charge transfer as the rebar was exposed to chloride solution. In the presence of high concentrations of sulfate ions in the electrolyte, generation and dissolution of the passive film proceeded simultaneously and corrosion was mainly controlled by the diff usion rate. When Na2SO4 and NaCl were added to Ca(OH)2 solution, the instantaneous corrosion rate decreased by a factor of 10 to 20 as a result of the higher pH of the corroding solution.

Stress-corrosion cracking in metals

NASA Technical Reports Server (NTRS)

1971-01-01

Criteria and recommended practices for preventing stress-corrosion cracking from impairing the structural integrity and flightworthiness of space vehicles are presented. The important variables affecting stress-corrosion cracking are considered to be the environment, including time and temperature; metal composition, and structure; and sustained tensile stress. For designing spacecraft structures that are free of stress-corrosion cracking for the service life of the vehicle the following rules apply: (1) identification and control of the environments to which the structure will be exposed during construction, storage, transportation, and use; (2) selection of alloy compositions and tempers which are resistant to stress-corrosion cracking in the identified environment; (3) control of fabrication and other processes which may introduce residual tensile stresses or damage the material; (4) limitation of the combined residual and applied tensile stresses to below the threshold stress level for the onset of cracking throughout the service life of the vehicle; and (5) establishment of a thorough inspection program.

Development of an Accelerated Test Method for the Determination of Susceptibility to Atmospheric Corrosion

NASA Technical Reports Server (NTRS)

Ambrose, John R.

1991-01-01

The theoretical rationale is presented for use of a repetitive cyclic current reversal voltammetric technique for characterization of localized corrosion processes, including atmospheric corrosion. Applicability of this proposed experimental protocol is applied to characterization of susceptibility to crevice and pitting corrosion, atmospheric corrosion and stress corrosion cracking. Criteria upon which relative susceptibility is based were determined and tested using two iron based alloys commonly in use at NASA-Kennedy; A36 (a low carbon steel) and 4130 (a low alloy steel). Practicality of the procedure was demonstrated by measuring changes in anodic polarization behavior during high frequency current reversal cycles of 25 cycles per second with 1 mA/sq cm current density amplitude in solutions containing Cl anions. The results demonstrated that, due to excessive polarization which affects conductivity of barrier corrosion product layers, A36 was less resistant to atmospheric corrosion than its 4130 counterpart; behavior which was also demonstrated during exposure tests.

Localized corrosion of high performance metal alloys in an acid/salt environment

NASA Technical Reports Server (NTRS)

Macdowell, L. G.; Ontiveros, C.

1991-01-01

Various vacuum jacketed cryogenic supply lines at the Space Shuttle launch site at Kennedy Space Center use convoluted flexible expansion joints. The atmosphere at the launch site has a very high salt content, and during a launch, fuel combustion products include hydrochloric acid. This extremely corrosive environment has caused pitting corrosion failure in the thin walled 304L stainless steel flex hoses. A search was done to find a more corrosion resistant replacement material. The study focussed on 19 metal alloys. Tests which were performed include electrochemical corrosion testing, accelerated corrosion testing in a salt fog chamber, and long term exposure at a beach corrosion testing site. Based on the results of these tests, several nickel based alloys were found to have very high resistance to this corrosive environment. Also, there was excellent agreement between the electrochemical tests and the actual beach exposure tests. This suggests that electrochemical testing may be useful for narrowing the field of potential candidate alloys before subjecting samples to long term beach exposure.

Localized CO2 corrosion of carbon steel with different microstructures in brine solutions with an imidazoline-based inhibitor

NASA Astrophysics Data System (ADS)

Zhang, Huan-huan; Pang, Xiaolu; Gao, Kewei

2018-06-01

CO2 corrosion behavior of carbon steel with different microstructures (H steel: coarse laminar pearlite; T steel: globular and shot rod shaped pearlite) was analyzed in 3 wt.% NaCl solution at 60 °C with imidazoline-based inhibitor by electrochemical and weight loss methods. Electrochemical measurements showed that, compared to H steel, the inhibitor film adsorbed on T steel had a higher pitting corrosion resistance and the inhibition efficiency for T steel was larger at each concentration of inhibitor. Weight loss results exhibited that both steels suffered general corrosion in absence of inhibitor; however, localized corrosion was observed on the samples with insufficient concentration of inhibitor. H steel suffered more severe localized corrosion than T steel, it was related to that H steel had a higher density of dislocations in the pearlite area and the larger driving force for galvanic corrosion. The localized corrosion on H steel mainly distributed on the laminar pearlite area.

Durable Hybrid Coatings

DTIC Science & Technology

2011-01-01

be an adequate alternative for chromate-based coatings [Nanna,   2004] for the protection of aluminum alloys from corrosion . Its protection behavior ...alternative for chromate-based coatings for the protection of aluminum alloys from corrosion . Their protection behavior was attributed to a combination...Topcoat Under Prohesion® Conditions ........ 12 2.4 Remote Corrosion Sensor Design

77 FR 26156 - Airworthiness Directives; Cessna Aircraft Company Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-03

... surrounding components (wheel base, side rim, lock ring) for damage (such as corrosion, cracks, dents, bent areas, damaged or missing paint or primer, or wear on the metal), and of the bearing cup for corrosion... and surrounding components (wheel base, side rim, lock ring) for damage (such as corrosion, cracks...

PEO of pre-anodized Al-Si alloys: Corrosion properties and influence of sealings

NASA Astrophysics Data System (ADS)

Mohedano, M.; Matykina, E.; Arrabal, R.; Mingo, B.; Pardo, A.

2015-08-01

Voltage-controlled PEO coatings were developed on A356 aluminum alloys (gravity-cast and rheocast) with a pre-anodized layer. The influence of the alloy manufacturing process and the effect of Si-rich phase on the structure and composition of the oxide layers were evaluated using SEM, EDS and XRD. The pre-anodized oxide layer preserves the microstructure of the substrate due to the presence of secondary phases that have a different behavior relative to the matrix during anodizing. PEO coatings consisted of a mixture of α-Al2O3, γ-Al2O3 and mullite. The corrosion behavior and the effectiveness of different sealing techniques based on salts of nickel, cobalt, cerium and phosphonic acid were also studied. Post-treatments improved the hydrophobic properties of the coatings and showed a beneficial effect, significantly increasing the coating impedance and thereby reducing the susceptibility to corrosion.

Corrosion and protection of NdFeB type magnets

NASA Astrophysics Data System (ADS)

Cavalloti, P.; Bozzini, B.; Cecchini, R.; Bava, G. F.; Davies, H. A.; Hoggarth, C.

1992-02-01

A general mechanism for the corrosion behaviour of NdFeB magnets is presented, related to the magnet heterogeneity with the presence of different phases. Cathodic control is outlined. An electrochemical method to assess the corrosion resistance of magnets, with and without coatings, is proposed; it is based on the study of the transient voltage at the magnet surface after a second cathodic current pulse in a suitable aggressive solution and its dependence on the amount of cathodic current circulating. Suitable pretreatments have been tried and interesting results obtained with passivation pretreatments, giving phosphorous Nd at grain boundaries. Coatings if sintered and plastic magnets have been tried using several methods. Good results are obtained with Zn-Co layers on sintered magnets and a sol-gel glass on powders for plastic magnets. Improved ACS (Autocatalytic Chemical Deposition) Ni=P coatings have been realized, with an alkaline brass flash plating to start ACD deposition.

Fabrication of near-field optical apertures in aluminium by a highly selective corrosion process in the evanescent field.

PubMed

Haefliger, D; Stemmer, A

2003-03-01

A simple, one-step process to fabricate high-quality apertures for scanning near-field optical microscope probes based on aluminium-coated silicon nitride cantilevers is presented. A thin evanescent optical field at a glass-water interface was used to heat the aluminium at the tip apex due to light absorption. The heat induced a breakdown of the passivating oxide layer and local corrosion of the metal, which selectively exposed the front-most part of the probe tip from the aluminium. Apertures with a protruding silicon nitride tip up to 72 nm in height were fabricated. The height of the protrusion was controlled by the extent of the evanescent field, whereas the diameter depended on the geometry of the probe substrate. The corrosion process proved to be self-terminating, yielding highly reproducible tip heights. Near-field optical resolution in a transmission mode of 85 nm was demonstrated.

Biomedical coatings on magnesium alloys - a review.

PubMed

Hornberger, H; Virtanen, S; Boccaccini, A R

2012-07-01

This review comprehensively covers research carried out in the field of degradable coatings on Mg and Mg alloys for biomedical applications. Several coating methods are discussed, which can be divided, based on the specific processing techniques used, into conversion and deposition coatings. The literature review revealed that in most cases coatings increase the corrosion resistance of Mg and Mg alloys. The critical factors determining coating performance, such as corrosion rate, surface chemistry, adhesion and coating morphology, are identified and discussed. The analysis of the literature showed that many studies have focused on calcium phosphate coatings produced either using conversion or deposition methods which were developed for orthopaedic applications. However, the control of phases and the formation of cracks still appear unsatisfactory. More research and development is needed in the case of biodegradable organic based coatings to generate reproducible and relevant data. In addition to biocompatibility, the mechanical properties of the coatings are also relevant, and the development of appropriate methods to study the corrosion process in detail and in the long term remains an important area of research. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Hot corrosion testing of Ni-based alloys and coatings in a modified Dean rig

NASA Astrophysics Data System (ADS)

Steward, Jason Reid

Gas turbine blades are designed to withstand a variety of harsh operating conditions. Although material and coating improvements are constantly administered to increase the mean time before turbine refurbishment or replacement, hot corrosion is still considered as the major life-limiting factor in many industrial and marine gas turbines. A modified Dean rig was designed and manufactured at Tennessee Technological University to simulate the accelerated hot corrosion conditions and to conduct screening tests on the new coatings on Ni-based superalloys. Uncoated Ni-based superalloys, Rene 142 and Rene 80, were tested in the modified Dean rig to establish a testing procedure for Type I hot corrosion. The influence of surface treatments on the hot corrosion resistance was then investigated. It was found that grit-blasted specimens showed inferior hot corrosion resistance than that of the polished counterpart. The Dean rig was also used to test model MCrAlY alloys, pack cementation NiAl coatings, and electro-codeposited MCrAlY coatings. Furthermore, the hot corrosion attack on the coated-specimens were also assessed using a statistical analysis approach.

Influence of the pulsed plasma treatment on the corrosion resistance of the low-alloy steel plated by Ni-based alloy

NASA Astrophysics Data System (ADS)

Dzhumaev, P.; Yakushin, V.; Kalin, B.; Polsky, V.; Yurlova, M.

2016-04-01

This paper presents investigation results of the influence of high temperature pulsed plasma flows (HTPPF) treatment on the corrosion resistance of low-alloy steel 0.2C-Cr-Mn- Ni-Mo cladded by the rapidly quenched nickel-based alloy. A technique that allows obtaining a defect-free clad layer with a good adhesion to the substrate was developed. It is shown that the preliminary treatment of steel samples by nitrogen plasma flows significantly increases their corrosion resistance in the conditions of intergranular corrosion test in a water solution of sulfuric acid. A change of the corrosion mechanism of the clad layer from intergranular to uniform corrosion was observed as a result of sub-microcrystalline structure formation and homogeneous distribution of alloying elements in the plasma treated surface layer thus leading to the significant increase of the corrosion resistance.

Analysis of Tank 38H (HTF-38-15-47, 49) and Tank 43H (HTF-43-15-51, 53) surface and subsurface supernatant samples in support of enrichment and corrosion control programs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oji, L. N.

This report provides the results of analyses on Tanks 38H and 43H surface and subsurface supernatant liquid samples in support of the Enrichment Control Program (ECP) and the Corrosion Control Program (CCP).

Development of Computational Capabilities to Predict the Corrosion Wastage of Boiler Tubes in Advanced Combustion Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kung, Steven; Rapp, Robert

A comprehensive corrosion research project consisting of pilot-scale combustion testing and long-term laboratory corrosion study has been successfully performed. A pilot-scale combustion facility available at Brigham Young University was selected and modified to enable burning of pulverized coals under the operating conditions typical for advanced coal-fired utility boilers. Eight United States (U.S.) coals were selected for this investigation, with the test conditions for all coals set to have the same heat input to the combustor. In addition, the air/fuel stoichiometric ratio was controlled so that staged combustion was established, with the stoichiometric ratio maintained at 0.85 in the burner zonemore » and 1.15 in the burnout zone. The burner zone represented the lower furnace of utility boilers, while the burnout zone mimicked the upper furnace areas adjacent to the superheaters and reheaters. From this staged combustion, approximately 3% excess oxygen was attained in the combustion gas at the furnace outlet. During each of the pilot-scale combustion tests, extensive online measurements of the flue gas compositions were performed. In addition, deposit samples were collected at the same location for chemical analyses. Such extensive gas and deposit analyses enabled detailed characterization of the actual combustion environments existing at the lower furnace walls under reducing conditions and those adjacent to the superheaters and reheaters under oxidizing conditions in advanced U.S. coal-fired utility boilers. The gas and deposit compositions were then carefully simulated in a series of 1000-hour laboratory corrosion tests, in which the corrosion performances of different commercial candidate alloys and weld overlays were evaluated at various temperatures for advanced boiler systems. Results of this laboratory study led to significant improvement in understanding of the corrosion mechanisms operating on the furnace walls as well as superheaters and reheaters in coal-fired boilers resulting from the coexistence of sulfur and chlorine in the fuel. A new corrosion mechanism, i.e., “Active Sulfidation Corrosion Mechanism,” has been proposed to account for the accelerated corrosion wastage observed on the furnace walls of utility boilers burning coals containing sulfur and chlorine. In addition, a second corrosion mechanism, i.e., “Active Sulfide-to-Oxide Corrosion Mechanism,” has been identified to account for the rapid corrosion attack on superheaters and reheaters. Both of the newly discovered corrosion mechanisms involve the formation of iron chloride (FeCl2) vapor from iron sulfide (FeS) and HCl, followed by the decomposition of FeCl2 via self-sustaining cycling reactions. For higher alloys containing sufficient chromium, the attack on superheaters and reheaters is dominated by Hot Corrosion in the presence of a fused salt. Furthermore, two stages of the hot corrosion mechanism have been identified and characterized in detail. The initiation of hot corrosion attack induced by molten sulfate leads to Stage 1 “acidic” fluxing and re-precipitation of the protective scale formed initially on the deposit-covered alloy surfaces. Once the protective scale is penetrated, Stage 2 Hot Corrosion is initiated, which is dominated by “basic” fluxing and re-precipitation of the scale in the fused salt. Based on the extensive corrosion information generated from this project, corrosion modeling was performed using non-linear regression analysis. As a result of the modeling efforts, two predictive equations have been formulated, one for furnace walls and the other for superheaters and reheaters. These first-of-the-kind equations can be used to estimate the corrosion rates of boiler tubes based on coal chemistry, alloy compositions, and boiler operating conditions for advanced boiler systems.« less

Identification of controlling factors for the initiation of corrosion of fresh concrete sewers.

PubMed

Jiang, Guangming; Sun, Xiaoyan; Keller, Jurg; Bond, Philip L

2015-09-01

The development of concrete corrosion in new sewer pipes undergoes an initiation process before reaching an active corrosion stage. This initiation period is assumed to last several months to years but the key factors affecting the process, and its duration, are not well understood. This study is therefore focused on this initial stage of the corrosion process and the effect of key environmental factors. Such knowledge is important for the effective management of corrosion in new sewers, as every year of life extension of such systems has a very high financial benefit. This long-term (4.5 year) study has been conducted in purpose-built corrosion chambers that closely simulated the sewer environment, but with control of three key environmental factors being hydrogen sulfide (H2S) gas phase concentration, relative humidity and air temperature. Fresh concrete coupons, cut from an industry-standard sewer pipe, were exposed to the corrosive conditions in the chambers, both in the gas phase and partially submerged in wastewater. A total of 36 exposure conditions were investigated to determine the controlling factors by regular retrieval of concrete coupons for detailed analysis of surface pH, sulfur compounds (elemental sulfur and sulfate) and concrete mass loss. Corrosion initiation times were thus determined for different exposure conditions. It was found that the corrosion initiation time of both gas-phase and partially-submerged coupons was positively correlated with the gas phase H2S concentration, but only at levels of 10 ppm or below, indicating that sulfide oxidation rate rather than the H2S concentration was the limiting factor during the initiation stage. Relative humidity also played a role for the corrosion initiation of the gas-phase coupons. However, the partially-submerged coupons were not affected by humidity as these coupons were in direct contact with the sewage and hence did have sufficient moisture to enable the microbial processes to proceed. The corrosion initiation time was also shortened by higher gas temperature due to its positive impact on reaction kinetics. These findings provide real opportunities for pro-active sewer asset management with the aim to delay the on-set of the corrosion processes, and hence extend the service life of sewers, through improved prediction and optimization capacity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Corrosion of titanium: Part 1: aggressive environments and main forms of degradation.

PubMed

Prando, Davide; Brenna, Andrea; Diamanti, Maria Vittoria; Beretta, Silvia; Bolzoni, Fabio; Ormellese, Marco; Pedeferri, MariaPia

2017-11-11

Titanium has outstanding corrosion resistance due to the external natural oxide protective layer formed when it is exposed to an aerated environment. Despite this, titanium may suffer different forms of corrosion in severe environments: uniform corrosion, pitting and crevice corrosion, hydrogen embrittlement, stress-corrosion cracking, fretting corrosion and erosion. In this first review, forms of corrosion affecting titanium are analyzed based on a wide literature review. For each form of corrosion, the mechanism and most severe environment are reported according to the current understanding.In the second part, this review will address the possible surface treatments that can increase corrosion resistance on commercially pure titanium: Electrochemical anodizing, thermal oxidation, chemical oxidation and bulk treatments such as alloying will be considered, highlighting the advantages of each technique.

DEVELOPMENT OF AN ENVIRONMENTALLY BENIGN MICROBIAL INHIBITOR TO CONTROL INTERNAL PIPELINE CORROSION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bill W. Bogan; Brigid M. Lamb; Gemma Husmillo

The overall program objective is to develop and evaluate environmentally benign agents or products that are effective in the prevention, inhibition, and mitigation of microbially influenced corrosion (MIC) in the internal surfaces of metallic natural gas pipelines. The goal is to develop one or more environmentally benign (a.k.a. ''green'') products that can be applied to maintain the structure and dependability of the natural gas infrastructure. Various chemicals that inhibit the growth and/or the metabolism of corrosion-associated microbes such as sulfate reducing bacteria, denitrifying bacteria, and methanogenic bacteria were evaluated to determine their ability to inhibit corrosion in experiments utilizing puremore » and mixed bacterial cultures, and planktonic cultures as well as mature biofilms. Planktonic cultures are easier to inhibit than mature biofilms but several compounds were shown to be effective in decreasing the amount of metal corrosion. Of the compounds tested hexane extracts of Capsicum pepper plants and molybdate were the most effective inhibitors of sulfate reducing bacteria, bismuth nitrate was the most effective inhibitor of nitrate reducing bacteria, and 4-((pyridine-2-yl)methylamino)benzoic acid (PMBA) was the most effective inhibitor of methanogenic bacteria. All of these compounds were demonstrated to minimize corrosion due to MIC, at least in some circumstances. The results obtained in this project are consistent with the hypothesis that any compound that disrupts the metabolism of any of the major microbial groups present in corrosion-associated biofilms shows promise in limiting the amount/rate of corrosion. This approach of controlling MIC by controlling the metabolism of biofilms is more environmentally benign than the current approach involving the use of potent biocides, and warrants further investigation.« less

Cellulose acetate layer effect toward aluminium corrosion rate in hydrochloric acid media

NASA Astrophysics Data System (ADS)

Andarany, K. S.; Sagir, A.; Ahmad, A.; Deni, S. K.; Gunawan, W.

2017-09-01

Corrosion occurs due to the oxidation and reduction reactions between the material and its environment. The oxidation reaction defined as reactions that produce electrons and reduction is between two elements that bind the electrons. Corrosion cannot be inevitable in life both within the industry and household. Corrosion cannot eliminate but can be control. According to the voltaic table, Aluminum is a metal that easily corroded. This study attempts to characterize the type of corrosion by using a strong acid media (HCl). Experiment using a strong acid (HCl), at a low concentration that occurs is pitting corrosion, whereas at high concentrations that occurs is corrosion erosion. One of prevention method is by using a coating method. An efforts are made to slow the rate of corrosion is by coating the metal with “cellulose acetate” (CA). cellulose acetate consisted of cellulose powder dissolved in 99% acetic acid, and then applied to the aluminum metal. Soaking experiments using hydrochloric acid, cellulose acetate is able to slow down the corrosion rate of 47 479%.

Effects of impurities on the biodegradation behavior of pure magnesium

NASA Astrophysics Data System (ADS)

Lee, Ji-Young; Han, Gilsoo; Kim, Yu-Chan; Byun, Ji-Young; Jang, Jae-il; Seok, Hyun-Kwang; Yang, Seok-Jo

2009-12-01

The corrosion behavior of pure magnesium that has different content ratio of impurities (such as Fe/Mn ratio) in Hanks' solution was investigated in order to tailor the lifetime of biodegradable implant made of pure magnesium. Two distinct stages of corrosion were observed: a slow corrosion rate stage and a subsequent fast corrosion rate stage. The first stage was characterized by uniform corrosion that produced magnesium hydroxide and calcium phosphate film on a magnesium surface, resulting in a slow corrosion rate. The second stage with an abrupt increase in the corrosion rate was induced by Fe precipitates and was stimulated by an increase in the Fe/Mn ratio. This corrosion was developed to a preferred crystallographic pitting corrosion where the pits propagated along the preferred crystallographic plane and several layers of Mg planes with narrow interplanar space remained uncorroded. From this study, it is expected that the lifetime of the biodegradable implant made of pure Mg can be tailored by controlling the amount and ratio of the impurities.

Lead Sampling Protocols: Why So Many and What Do They Tell You?

EPA Science Inventory

Sampling protocols can be broadly categorized based on their intended purpose of 1) Pb regulatory compliance/corrosion control efficacy, 2) Pb plumbing source determination or Pb type identification, and 3) Pb exposure assessment. Choosing the appropriate protocol is crucial to p...

Development and Testing of a Linear Polarization Resistance Corrosion Rate Probe for Ductile Iron Pipe (Web Report 4361)

EPA Science Inventory

The North American water and wastewater community has hundreds of millions of feet of ductile iron pipe in service. Only a portion of the inventory has any form of external corrosion control. Ductile iron pipe, in certain environments, is subject to external corrosion.Linear Pola...

AN INVESTIGATION OF THE IMPACT OF ALLOY COMPOSITION AND PH ON THE CORROSION OF BRASS IN DRINKING WATER

EPA Science Inventory

A better understanding of brass corrosion may provide information and guidance on the use of the safest materials for the production of plumbing fixtures, and optimization of corrosion control treatments. The effect of alloy composition and pH on the metal leached from six differ...

49 CFR 195.585 - What must I do to correct corroded pipe?

Code of Federal Regulations, 2011 CFR

2011-10-01

... TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.585 What must I do to correct corroded pipe? (a) General corrosion. If you find pipe so generally corroded that the remaining wall thickness... restore the serviceability of the pipe. (b) Localized corrosion pitting. If you find pipe that has...

49 CFR 192.487 - Remedial measures: Distribution lines other than cast iron or ductile iron lines.

Code of Federal Regulations, 2011 CFR

2011-10-01

... STANDARDS Requirements for Corrosion Control § 192.487 Remedial measures: Distribution lines other than cast iron or ductile iron lines. (a) General corrosion. Except for cast iron or ductile iron pipe, each... engineering tests and analyses show can permanently restore the serviceability of the pipe. Corrosion pitting...

49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

Code of Federal Regulations, 2011 CFR

2011-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action under...

49 CFR 195.585 - What must I do to correct corroded pipe?

Code of Federal Regulations, 2010 CFR

2010-10-01

... TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.585 What must I do to correct corroded pipe? (a) General corrosion. If you find pipe so generally corroded that the remaining wall thickness... restore the serviceability of the pipe. (b) Localized corrosion pitting. If you find pipe that has...

49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

Code of Federal Regulations, 2010 CFR

2010-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action under...

49 CFR 192.487 - Remedial measures: Distribution lines other than cast iron or ductile iron lines.

Code of Federal Regulations, 2013 CFR

2013-10-01

... STANDARDS Requirements for Corrosion Control § 192.487 Remedial measures: Distribution lines other than cast iron or ductile iron lines. (a) General corrosion. Except for cast iron or ductile iron pipe, each... engineering tests and analyses show can permanently restore the serviceability of the pipe. Corrosion pitting...

49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

Code of Federal Regulations, 2014 CFR

2014-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action under...

49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

Code of Federal Regulations, 2012 CFR

2012-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action under...

49 CFR 192.487 - Remedial measures: Distribution lines other than cast iron or ductile iron lines.

Code of Federal Regulations, 2012 CFR

2012-10-01

... STANDARDS Requirements for Corrosion Control § 192.487 Remedial measures: Distribution lines other than cast iron or ductile iron lines. (a) General corrosion. Except for cast iron or ductile iron pipe, each... engineering tests and analyses show can permanently restore the serviceability of the pipe. Corrosion pitting...

49 CFR 195.585 - What must I do to correct corroded pipe?

Code of Federal Regulations, 2012 CFR

2012-10-01

... TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.585 What must I do to correct corroded pipe? (a) General corrosion. If you find pipe so generally corroded that the remaining wall thickness... restore the serviceability of the pipe. (b) Localized corrosion pitting. If you find pipe that has...

49 CFR 195.585 - What must I do to correct corroded pipe?

Code of Federal Regulations, 2013 CFR

2013-10-01

... TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.585 What must I do to correct corroded pipe? (a) General corrosion. If you find pipe so generally corroded that the remaining wall thickness... restore the serviceability of the pipe. (b) Localized corrosion pitting. If you find pipe that has...

49 CFR 192.487 - Remedial measures: Distribution lines other than cast iron or ductile iron lines.

Code of Federal Regulations, 2014 CFR

2014-10-01

... STANDARDS Requirements for Corrosion Control § 192.487 Remedial measures: Distribution lines other than cast iron or ductile iron lines. (a) General corrosion. Except for cast iron or ductile iron pipe, each... engineering tests and analyses show can permanently restore the serviceability of the pipe. Corrosion pitting...

49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

Code of Federal Regulations, 2013 CFR

2013-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action under...

49 CFR 195.585 - What must I do to correct corroded pipe?

Code of Federal Regulations, 2014 CFR

2014-10-01

... TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.585 What must I do to correct corroded pipe? (a) General corrosion. If you find pipe so generally corroded that the remaining wall thickness... restore the serviceability of the pipe. (b) Localized corrosion pitting. If you find pipe that has...

49 CFR 192.455 - External corrosion control: Buried or submerged pipelines installed after July 31, 1971.

Code of Federal Regulations, 2010 CFR

2010-10-01

... minimum, soil resistivity measurements and tests for corrosion accelerating bacteria, that a corrosive environment does not exist. However, within 6 months after an installation made pursuant to the preceding sentence, the operator shall conduct tests, including pipe-to-soil potential measurements with respect to...

[Use of corrosion inhibitors during the presterilization preparation of medical instruments].

PubMed

Sverdlov, A I; Sher, L B; Kochanova, L G

1978-01-01

Corrosion inhibitors that may be used for pre-sterilization treatment of medical instruments are described and investigated. The investigation included potentiostatic and gravimetric measurements along with the visual control. It was found that in order to reduce the corrosion activity of detergent solutions the use of bi-substituted sodium phosphate is advisable.

Galvanic corrosion of nitinol under deaerated and aerated conditions.

PubMed

Pound, Bruce G

2016-10-01

Various studies have examined the corrosion rate of nitinol generally under deaerated conditions. Likewise, galvanic corrosion studies have typically involved deaerated solutions. This work addressed the effect of galvanic coupling on the corrosion current of electropolished nitinol in phosphate buffered saline and 0.9% sodium chloride under dearated and aerated conditions for times up to 24 h. Tests were performed on nitinol alone and coupled with MP35N in both the mechanically polished and passivated conditions. Aeration and galvanic coupling were found to have relatively little effect, indicating that the corrosion current is controlled by the anodic reaction. The current can be attributed entirely to Ni(2+) dissolution, which appears to be governed by solid-state mass transport of Ni(2+) through the passive oxide film. Because corrosion of EP nitinol is controlled by the anodic reaction, contact between EP nitinol and MP35N or other biomedical Co-Cr alloys is unlikely to result in significant galvanic effects in vivo. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1322-1327, 2016. © 2015 Wiley Periodicals, Inc.

Investigation of Internal Corrosion and Corrosion-Control Alternatives in Commercial Tankships.

DTIC Science & Technology

1981-07-01

high sulfur crude, scale on - the sides of the tank may become impregnated with sulfur. The compound formed is pyrophoric iron sulfide .2 7 The...Stiansen - LisLon Mr. M. Touna AMERICAN IRON & STEEL INSTITUTE NATIONAL ACADEMY OF SCIENCES SHIP RESEARCH COMMITTEEMrR.HStne-Lso Mr. A. Dudley Neff...to contribute to corrosion in a tank. In crude oil, the most significant corrosive component is the hydrogen sulfide which it contains. Most oils

40 CFR 267.194 - What installation requirements must I follow?

Code of Federal Regulations, 2011 CFR

2011-07-01

... settlement, vibration, expansion, or contraction. (b) You must provide the type and degree of corrosion protection recommended by an independent corrosion expert, based on the information provided under § 267.191... corrosion expert must supervise the installation of a corrosion protection system that is field fabricated...

40 CFR 267.194 - What installation requirements must I follow?

Code of Federal Regulations, 2010 CFR

2010-07-01

... settlement, vibration, expansion, or contraction. (b) You must provide the type and degree of corrosion protection recommended by an independent corrosion expert, based on the information provided under § 267.191... corrosion expert must supervise the installation of a corrosion protection system that is field fabricated...

40 CFR 267.194 - What installation requirements must I follow?

Code of Federal Regulations, 2012 CFR

2012-07-01

... settlement, vibration, expansion, or contraction. (b) You must provide the type and degree of corrosion protection recommended by an independent corrosion expert, based on the information provided under § 267.191... corrosion expert must supervise the installation of a corrosion protection system that is field fabricated...

40 CFR 267.194 - What installation requirements must I follow?

Code of Federal Regulations, 2014 CFR

2014-07-01

... settlement, vibration, expansion, or contraction. (b) You must provide the type and degree of corrosion protection recommended by an independent corrosion expert, based on the information provided under § 267.191... corrosion expert must supervise the installation of a corrosion protection system that is field fabricated...

40 CFR 267.194 - What installation requirements must I follow?

Code of Federal Regulations, 2013 CFR

2013-07-01

... settlement, vibration, expansion, or contraction. (b) You must provide the type and degree of corrosion protection recommended by an independent corrosion expert, based on the information provided under § 267.191... corrosion expert must supervise the installation of a corrosion protection system that is field fabricated...

Simultaneous Compliance and Corrosion Control: Myth versus Reality

EPA Science Inventory

a segment examining “nuts and bolts” examples of corrosion control strategies that have been implemented and which requiredmodifications when “things did not go according to plan”. The process of an ongoing review of data and feedback gathered on a continuousbasis in “real time” ...

Evaluation of corrosion and corrosion control on interstate 89 bridge #30 and #31.

DOT National Transportation Integrated Search

2015-06-01

This report summarizes the evaluation of the performance of cathodic protection installed on I-89 bridges over : Gile Pond Road (NH Route 114) during a rehabilitation project in 1987. : Control bridges of I-89 over Hominy Pot Road, approximately 1.5 ...

49 CFR 192.475 - Internal corrosion control: General.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Internal corrosion control: General. 192.475 Section 192.475 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE:...

49 CFR 192.475 - Internal corrosion control: General.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Internal corrosion control: General. 192.475 Section 192.475 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE:...

49 CFR 192.477 - Internal corrosion control: Monitoring.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Internal corrosion control: Monitoring. 192.477 Section 192.477 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELIN...

49 CFR 192.475 - Internal corrosion control: General.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Internal corrosion control: General. 192.475 Section 192.475 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE:...

49 CFR 192.477 - Internal corrosion control: Monitoring.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Internal corrosion control: Monitoring. 192.477 Section 192.477 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELIN...

49 CFR 192.477 - Internal corrosion control: Monitoring.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Internal corrosion control: Monitoring. 192.477 Section 192.477 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELIN...

Characterization of iron carbonate scales developed under carbon dioxide corrosion conditions

NASA Astrophysics Data System (ADS)

de Moraes, Flavio Dias

1999-11-01

Carbon steel CO2 corrosion is a common and very serious problem in the oil industry. It often results in severe damage to pipes and equipment. Besides controlling direct costs associated with loss of production and replacement or repair to the equipment damaged by corrosion, life and environmental safety must be protected with the thorough study of this type of corrosion. For a given type of steel, the CO2 corrosion rates are strongly influenced by many mechanical and environmental factors, such as flow velocity, temperature, gas-liquid ratio, oil-water ratio, CO2 partial pressure, and the chemical composition of the produced water. Under specific conditions, a corrosion product, the iron carbonate (FeCO3), can deposit over the corroding metal as a scale and dramatically reduce the CO2 corrosion rates on carbon steels. The ability to reliably predict the protective characteristics of such scales so that this knowledge may be used to mitigate the CO2 corrosion problem is the main objective of this research. CO2 corrosion tests performed under various CO2 corrosion flowing conditions in a flow loop were used to generate and study FeCO3 scales. In situ Electrochemical Impedance Spectroscopy (EIS) techniques were successfully used to monitor the development of the scales throughout the duration of the tests. The EIS monitoring enabled the identification of the type of scales being formed and the quantification of the protection they give. A procedure using EIS, SEM and X-ray diffraction was developed to electrochemically and morphologically characterize the scales formed. In this work, morphology of the scales was proved to be the most important characteristic related to CO2 corrosion protection, and temperature was found to be the main environmental parameter controlling the morphology of the scales. For the environmental conditions tested, a correlation was developed to predict the type of iron carbonate scales that would be formed and the amount of CO2 corrosion protection these scales would provide to carbon steels.

Characterization of corrosion phenomena and kinetics on T91 ferritic/martensitic steel exposed at 450 and 550 °C to flowing Pb-Bi eutectic with 10-7 mass% dissolved oxygen

NASA Astrophysics Data System (ADS)

Tsisar, Valentyn; Schroer, Carsten; Wedemeyer, Olaf; Skrypnik, Aleksandr; Konys, Jürgen

2017-10-01

Corrosion behavior of two heats of T91 ferritic/martensitic steel, with slightly different Cr content, was investigated in flowing (2 m/s) Pb-Bi with 10-7 mass%O at 450 and 550 °C. The observed corrosion modes are: protective scale formation; accelerated oxidation and solution-based corrosion attack. Accelerated oxidation at 450 °C results in general metal recession of about 10 μm after ∼9000 h exposure and ∼15 μm at 550 °C after 2000 h. More severe and local solution-based corrosion results in a maximum depth of attack of 50-960 μm and 115-190 μm, correspondingly. Incubation period for solution-based corrosion is 500-5000 h at 450 °C and ≤500 h at 550 °C. The slightly higher chromium content in one of the heat of T91 steel prolongs the incubation period by improving the stability of the Cr-based oxide film.