316L不锈钢板式换热器使用约半年后频繁出现泄漏事故，通过扫描电镜分析、能谱分析、金相检验、显微硬度检测和有限元模拟分析等方法对泄漏原因进行了分析。结果表明：316L不锈钢板片发生了应力腐蚀开裂，造成泄漏。板片冷加工后产生了较大的残余拉应力且环境中存在Cl^-腐蚀介质，导致残余应力较大的波峰和波谷处产生裂纹和腐蚀坑，是造成板片发生早期开裂的主要原因，而高温工作环境加速了点蚀的产生及裂纹的萌生和扩展，最终板片发生泄漏。

The leakage accidents of 316L stainless steel plate heat exchanger occurred frequently after using for about half a year. The causes of leakage were analyzed by means of scanning electron microscope, energy spectrum analysis, metallographic examination, microhardness test and finite element simulation analysis. The results show that stress corrosion cracking occurred in 316L stainless steel plate, resulting in leakage. Large residual tensile stress and Cl^- corrosion medium existed in the environment after cold working, leading to cracks and corrosion pits at the wave crest and valley with large residual stress, which were the main reason for the early cracking of plate. High temperature working environment accelerated the generation of pitting corrosion and the initiation and propagation of cracks, and finally the plate leaked.