The effects of heat treatments on the susceptibility to environment-induced cracking (EIC) of the CF8A stainless steel (SS) in simulated water of a boiling water reactor (BWR) were investigated by slow strain-rate tensile (SSRT) tests. Different microstructures were resulted by subjecting the as-casted CF8A to stress relief treatment (1050 °C/2 h, C sample), thermal aging (385 °C/20000 h, A sample), recovery annealing (500 °C/1 h, R sample) or solution annealing (1200 °C/2 h, S sample). The results indicated that after aging treatment (A sample), a decrease in tensile ductility and impact toughness was resulted relative to the un-aged specimens. Recovery annealing (R sample) caused an improved tensile ductility and impact toughness of the embrittled CF8A. Excessive solution (S sample) led to an obvious decrease in tensile strength but increase in ductility and toughness of the CF8A. The EIC susceptibility of the tested samples in simulated BWR water increased in the order: S < C < R < A samples. The cracks in distinct CF8A specimens were found to initiate at and propagate along δ/γ interfaces in simulated BWR water. The lowered ferrite content and change in ferrite morphology accounted for the superior EIC resistance of the S sample relative to that of the other ones in simulated BWR water.

通过慢应变速率拉伸（SSRT）试验研究了热处理对沸水反应堆（BWR）模拟水中CF8A不锈钢（SS）的环境诱导开裂（EIC）敏感性的影响。通过对铸态CF8A进行应力消除处理（1050°C / 2 h，C样品），热老化（385°C / 20000 h，A样品），恢复退火（500°C / 1 h），得到不同的微观结构，R样品）或固溶退火（1200°C / 2 h，S样品）。结果表明，经过时效处理（样品）后，与未时效样品相比，拉伸延展性和冲击韧性降低。恢复退火（R样品）使脆化的CF8A的拉伸延展性和冲击韧性得到改善。过多的溶液（S样品）会导致CF8A的抗拉强度明显下降，但延展性和韧性增加。测试样品在模拟BWR水中的EIC敏感性按以下顺序增加：S <C <R <A样品。发现在不同的CF8A标本中的裂纹始于模拟BWR水中的δ/γ界面并沿δ/γ界面扩展。在模拟的BWR水中，较低的铁素体含量和铁素体形态的变化是S样品相对于其他样品具有更高的EIC抗性。