High temperature intergranular embrittlement in commercial and S-,P-,S,P-doped type 304 stainless steels

학위논문(박사) - 한국과학기술원 : 재료공학과, 1986.8, [ viii, 144 p. ]한국과학기술원 : 재료공학과

Dynamic Strain Aging Behaviors in Nitrogen Alloyed Type 316L Stainless Steel

Tensile tests were conducted with varying strain rate (1×10^(-2)/sec∼2×10^(-4)/sec) at the test temperature range between room temperature and 750℃ to evaluate the effect of nitrogen on dynamic strain aging (DSA) behaviors in nitrogen added type 316L stainless steels. Yield and tensile strength increased without reduction of elongation with adding nitrogen. The temperature range and the critical strain for DSA increased with nitrogen addition. Types A and B serrations were observed at 600℃ and the strain for transition from type A to type B increased with nitrogen addition. Solute atoms for DSA were vacancies and chromium and the activation energy for DSA increased with adding nitrogen. The reason that nitrogen retarded DSA was explained by the fact that nitrogen reduced the chromium diffusion to dislocations due to the strong interaction between nitrogen and chromium

SA 508강 용접 열영향부의 미세 조직과 충격인성의 상관관계

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