材料期刊网

采用恒载荷试验方法及慢应变速率试验（SSRT）方法研究了渗铝304奥氏体不锈钢在沸腾42%MgCl2溶液中的应力腐蚀破裂（SCC）性能，分析了渗铝不锈钢SCC机理，讨论了不同试验方法对渗铝不锈钢SCC敏感性评价的影响。试验表明：渗铝处理可明显提高304钢抗SCC性能，其机理为渗铝层的环境遮断作用及对基体的电化学保护作用。两种方法在评价各种渗铝钢材料SCC性能方面有统一性：恒载荷试验中SCC敏感性指标σth高的材料，SSRT中SCC敏感性指标δi也相对较高。但两种方法中渗铝试样的断口形态表现出差异：恒载荷试验为穿晶型SCC断口，而SSRT无SCC断口特征，为韧性断口。

By means of constant load tests and slow strain rate tests(SSRT), the SCC behavior of aluminized 304 stainless steel in boiling 42% MgCl2 solution was studied. The SCC mechanism of aluminized 304 steel has been analyzed This paper mainly discusses the influence of different test means on the evaluation SCC susceptibility of aluminized 304 steel. Two test methods both show that aluminizing treatment improved the resistance to SCC of SUS 304, the mechanisms were the environment covering action and the electrochemical protective action of the aluminized layer. The two methods were the same in appraisal of SCC properties of aluminized 304 steel, the more the SCC target of constant load test(σth ),the more the SCC target of SSRT( δi),but the two means was different in the formation of fracture surface. The fracture of constant load tests was transgranular SCC mode, whereas the SSRT fracture surface was tough and without SCC fracture characteristics.