Abstract: The stress corrosion cracking（SCC）susceptibility of type 304 stainless steel in NaCl solution was studied by slow strain rate test（SSRT）. The fracture morphology of SCC was observed and analyzed by using scanning electron microscope（SEM）. A new instrument was designed to apply stress to the specimen of type 304 stainless steel. The effect of chloride concentration on the passive film crack potential was also studied in situ by using the electrochemical technology under constant strain. The critical chloride concentrations of SCC and passive film crack potential for type 304 stainless steel were obtained，and they were basically the same.

摘要： 通过慢拉伸实验得出了304不锈钢应力腐蚀敏感性与溶液中Cl－浓度的关系，用扫描电镜对拉伸试样的断口形貌进行了分析，得出了304不锈钢发生应力腐蚀的临界氯离子浓度。采用自行设计的装置对304不锈钢试样施加拉应力，通过恒应变条件下的电化学原位测试研究了304不锈钢钝化膜破裂电位与氯离子浓度的关系。得出导致钝化膜破裂电位突变的Cl－浓度与发生应力腐蚀破裂的临界Cl－浓度是基本一致的结论。