温度对P92耐热钢高温水中应力腐蚀开裂行为的影响  

Effect of temperature on stress corrosion cracking behaviour of P92 heat resistant steel in high temperature water

作　　者：张振[1] 胡正飞[1] 

机构地区：[1]同济大学材料科学与工程学院,上海201804

出　　处：《材料热处理学报》2015年第8期121-125,共5页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(50871076)

摘　　要：在高温水环境中采用线性伏安法和慢拉伸试验法,分别研究了温度对国产P92钢点蚀形核及应力腐蚀开裂的影响规律。线性伏安法结果表明:随着温度的提高,P92钢在水中的耐腐蚀性能逐渐降低,晶界处点蚀形核数增多;慢拉伸试验结果表明,P92钢在试验条件下具有应力腐蚀开裂敏感性和动态应变时效(DSA)倾向,且随温度升高增强。通过扫描电镜(SEM)对试样断口截面及侧面形貌进行分析,结果表明随着温度的升高,断口侧面应力腐蚀裂纹以沿晶形式向内扩展,断口边缘呈明显脆性断裂特征。The effect of temperature on pitting initiation and stress corrosion cracking （SCC） of domestic P92 steel in high temperature water was investigated using linear sweep vohammetry and slow strain rate tests （ SSRT）. The results of linear sweep voltammetry show that P92 steel has weaker corrosion resistance with the increase of temperature. Pits along the grain boundary are easier to initiate at higher temperature water. The results of SSRT exhibit that P92 steel has the tendency of dynamic strain aging （DSA） and the SCC sensitivity in this test and these trends are more obvious with the increase of temperature. Scanning electron microscopy （SEM） observation results show that SCCs initiate from the grain boundaries and propagate intergranularly into the matrix in higher temperature water, moreover the characteristic of brittle fracture is also observed at the edge of fracture.

关 键 词：P92钢 高温水 温度 应力腐蚀开裂 

分 类 号：TG172.82[金属学及工艺—金属表面处理]