某304不锈钢管道泄漏的失效分析

摘要

某氟化工企业304不锈钢管道在运行三年半后发生泄漏失效.通过直读光谱仪、光学显微镜、扫描电镜和X射线衍射仪等对失效部位材料的化学成分、显微组织、腐蚀形貌及腐蚀产物进行了分析.结果表明:该304不锈钢管道的失效主要为Cl-浓缩造成的点蚀穿孔,H2S的存在则对点蚀起到了促进作用.%Leakage failure occurred at a 304 stainless steel tube after working for three and a half years in a fluorine chemical enterprise.The chemical composition,microstructure,corrosion morphology and corrosion products of the material in failed part of 304 stainless steel tube were studied using direct reading spectrometry,optical microscopy,scanning electron microscopy and X-ray diffraction.The results show that the major failure mode was pitting corrosion and perforation due to local enrichment of Cl-in the tube,and the existence of H2S promoted pitting corrosion.