摘要
某厂锅炉给水预热器在投入使用3.5年后,管箱外壁近横焊缝处发现裂纹。该换热器设计材质为0Cr18Ni9,截取含有裂纹的试样,进行化学成分分析、金相分析、硬度检测、拉伸强度测试、裂纹分析和扫描电子显微镜分析。材质Cr元素含量17.75%,硬度306HV10,这两项检测结果不符合GB/T 4237—2007《不锈钢热轧钢板和钢带》要求;裂纹表面发现S元素。应力腐蚀是此次失效的主要原因。
After 3.5 years service, cracks were found on horizontal weld of shell wall of a boiler feed water preheater. The heat-exchanger was made of 0Cr18Ni9. Samples containing cracks were cut for chemical composition analysis, metallographic analysis, hardness testing, tensile testing, cracks analysis and scanning electron microscopy analysis. Two results didn＇t meet the requirement of GB / T 4237--2007 stainless steel hot-rolled steel sheet and strip, that＇s the content of Cr （17.75%） and the hardness 306 HV10; and S element was found on the crack surface. Stress corrosion was the main reason for the failure.
出处
《化工装备技术》
CAS
2011年第6期46-48,共3页
Chemical Equipment Technology
