燃机电厂304不锈钢三通管应力腐蚀开裂的原因

摘要

A 304 stainless steel three-way pipe in a gas turbine power plant cracked and induced a leakage.Stereoscopic microscopy,optical microscopy,spectrometer,SEM and EDS were adopted to do the macro and micro analysis of the three-way pipe.Results indicate that the crack was biforked.There were a large area of mud patterns on the fracture and the corrosion products contained high concentration chloride ion.All these facts proved that the crack was caused by stress corrosion cracking.Besides,the corresponding prevention and improvement measures were proposed as well.%某燃机电厂天然气输送管道的一只304不锈钢三通管发生了开裂泄漏.采用体视显微镜、光学显微镜、光谱仪、扫描电子显微镜(SEM)及X射线能谱(XRD)等检测技术对三通管样品进行了宏观及微观分析.结果表明:裂纹呈分叉状,断口存在大面积的泥状花样腐蚀产物并含有较高浓度的氯离子,充分表明裂纹是由于应力腐蚀开裂而形成的.同时,针对裂纹原因也给出了相应的预防及改善措施.