| Autor: |
Hirata, Hiroyuki, Omura, Tomohiko, Jotoku, Kana, Nakamura, Jun, Osuki, Takahiro |
| Předmět: |
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| Zdroj: |
Welding International; Dec2015, Vol. 29 Issue 12, p922-927, 6p, 1 Color Photograph, 1 Black and White Photograph, 1 Diagram, 2 Charts, 5 Graphs |
| Abstrakt: |
The effect of chemical compositions and microstructures on hydrogen embrittlement of austenitic stainless steel weld metals in high-pressure hydrogen gas was surveyed by using the slow strain rate test (SSRT). As a result, hydrogen embrittlement of the weld metal was hardly influenced by δ ferrite in the weld metal, but by stability of austenite phase, which was estimated by Md30 value or Ni equivalent. In the weld metal with poor stability of austenite, α′-martensite was formed near a crack induced by SSRT. In addition, although the crystal structure of α′-martensite is as same as δ ferrite, susceptibility of hydrogen embrittlement became higher with the increase in α′-martensite. The mechanism to explain the difference between δ ferrite and α′-martensite was considered as following. The hardness, which increases the hydrogen embrittlement susceptibility in bcc structure, is higher in α′-martensite than in δ ferrite. In addition, α′-martensite might be formed continuously with propagation of a crack. Therefore, the effect of α′-martensite on hydrogen embrittlement could be larger compared with δ ferrite. [ABSTRACT FROM PUBLISHER] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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