Topologically close-packed phase precipitation and thermal stability in alloy 22

Pan, Yiming; Dunn, Darrell S.; Cragnolino, Gustavo A.

doi:10.1007/s11661-005-0207-z

Cited by 12 publications

(14 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Laser peening or low plasticity burnishing are used to mitigate residual stresses in the outer closure lid. 4,30,65,73 As-welded alloy 22 shows a dendritic structure with TCP phases in the interdendritic regions. Post-weld heat treatments produce an increase in the amount and size of TCP precipitates in the welded material, which increases with both aging time and temperature.…”

Section: Metallurgical Variablesmentioning

confidence: 99%

“…65 Solution-annealing treatments can mitigate TCP precipitation in heat-affected zones but they are not completely effective in dissolving TCP precipitates in weldments. 73 Fabrication processes are assumed to extend the range of environmental conditions for crevice corrosion occurrence on alloy 22 to lower [Cl − ], lower T, lower E and higher R for inhibitors. 30,65 However, as discussed above for the case of TCP precipitation in thermally aged alloy 22, contradicting results are reported by different research groups.…”

Section: Metallurgical Variablesmentioning

confidence: 99%

See 1 more Smart Citation

Crevice corrosion of nickel-based alloys considered as engineering barriers of geological repositories

Carranza

Rodríguez

2017

npj Mater Degrad

View full text Add to dashboard Cite

Nickel-based alloys are considered among other candidate materials as engineering barriers of geological repositories due to their excellent corrosion resistance. These alloys possess unique advantages: they may be used in saturated and unsaturated repositories, hosted by practically any rock type, while also compatible with any (or no) backfill, and have minimal impact in other barriers. Alloy-22 (UNS N06022) has been the most studied of this class of alloys for its potential application in the proposed repositories (namely Yucca Mountain, USA). Crevice corrosion is however an important and often unintended degradation process that may limit the waste container lifetime if a nickel-based alloy is selected. Alloy susceptibility to crevice corrosion is influenced by environmental and metallurgical variables. This review gives an account of the current knowledge regarding crevice corrosion of nickel-based alloys as candidate materials for the corrosion-resistant layer of high-level nuclear waste containers. Although there is a significant amount of research supporting the use of nickel-based alloys for this application, the effect of the different variables on crevice corrosion resistance is described. Special focus is given to the current criterion for crevice corrosion occurrence in repository environments, recent works and criticisms. The presently established criterion appears robust for ruling out crevice corrosion in saturated repositories; however, the development of a less conservative criterion for crevice corrosion occurrence is necessary to use these alloys in unsaturated repositories.

show abstract

Section: Metallurgical Variablesmentioning

confidence: 99%

Section: Metallurgical Variablesmentioning

confidence: 99%

Crevice corrosion of nickel-based alloys considered as engineering barriers of geological repositories

Carranza

Rodríguez

2017

npj Mater Degrad

View full text Add to dashboard Cite

show abstract

“…The same authors found that welded material was less resistant to localized corrosion than MA material. 14,33,[73][74][75] On the contrary, Evans et al reported that the behavior of MA and ASW materials were the same regarding resistance to crevice corrosion. 13 According to Rebak, 28 the latter discrepancies come from the crevicing mechanism used by Evans et al, 13 which was more demanding to the specimen than the crevicing mechanism used by Dunn et al 74 and hence less sensitive to microstructure.…”

Section: Metallurgical Variablesmentioning

confidence: 99%

The crevice corrosion of Alloy 22 in the Yucca Mountain nuclear waste repository

Carranza

2008

JOM

View full text Add to dashboard Cite

How would you……describe the overall signifi cance of this paper?This paper demonstrates that much research and understanding has been done in the last fi ve years regarding the localized corrosion resistance of Alloy 22. This information is crucial for predicting the lifetime performance of the high-level nuclear waste containers of Yucca Mountain.…describe this work to a materials science and engineering professional with no experience in your technical specialty?This is a review of results obtained using electrochemical and corrosion tests to assess the environmental and metallurgical variables that affect the localized corrosion resistance of the nickel-based Alloy 22 (N06022). The main experimental result discussed here is the repassivation potential value, a parameter used to predict if Alloy 22 may be prone or not to suffer localized corrosion. …describe this work to a layperson?This work deals with the degradation of an alloy (metal) due to its interaction with the environment. This process is called corrosion (rusting) in which a metal reverts back to oxides of minerals by a mechanism of oxidation. This metal is planned to be used as a barrier between nuclear waste and the environment in a mountain in Nevada. The susceptibility of Alloy 22 (N06022) to crevice corrosion may depend on environmental and metallurgical variables. This paper summarizes the current fi ndings regarding the effect of many of these variables, such as pH, other inhibitive species and types of crevicing material, geometry, and applied torque. There are still contradictory results regarding the effect of metallurgical factors such as the presence of weld seams. Crevice corrosion stifl ing and arrest must be considered in evaluating the life expectancy of components made of Alloy 22.

show abstract

“…Thus, it is very important to quantify the phase precipitates so that the most suitable welding parameters that minimize the presence of these particles can be selected. To determine the percentage of secondary phases, allpurpose image processing and analysis software packages are frequently used (Pan et al, 2005).…”

Section: Introductionmentioning

confidence: 99%

Automatic evaluation of nickel alloy secondary phases from SEM images

Albuquerque

Silva

Menezes

et al. 2010

Microscopy Res & Technique

View full text Add to dashboard Cite

Quantitative metallography is a technique to determine and correlate the microstructures of materials with their properties and behavior. Generic commercial image processing and analysis software packages have been used to quantify material phases from metallographic images. However, these all-purpose solutions also have some drawbacks, particularly when applied to segmentation of material phases. To overcome such limitations, this work presents a new solution to automatically segment and quantify material phases from SEM metallographic images. The solution is based on a neuronal network and in this work was used to identify the secondary phase precipitated in the gamma matrix of a Nickel base alloy. The results obtained by the new solution were validated by visual inspection and compared with the ones obtained by a commonly used commercial software. The conclusion is that the new solution is precise, reliable and more accurate and faster than the commercial software.

show abstract

Topologically close-packed phase precipitation and thermal stability in alloy 22

Cited by 12 publications

References 11 publications

Crevice corrosion of nickel-based alloys considered as engineering barriers of geological repositories

Crevice corrosion of nickel-based alloys considered as engineering barriers of geological repositories

The crevice corrosion of Alloy 22 in the Yucca Mountain nuclear waste repository

Automatic evaluation of nickel alloy secondary phases from SEM images

Contact Info

Product

Resources

About