高Cl^-环境对M152和17-4PH高强钢应力腐蚀开裂行为的影响  

Effect of High Cl^- Environment on Stress Corrosion Cracking Behavior of M152 and 17-4PH High-strength Steels

作　　者：吴伟 郝文魁[1,2] 李晓刚 钟平[4] 董超芳 刘智勇[1] 肖葵[1] WU Wei;HAO Wen-kui;LI Xiao-gang;ZHONG Ping;DONG Chao-fang;LIU Zhi-yong;XIAO Kui(Corrosion and Protection Center,University of Science and Technology Beijing,Beijing 100083,China;State Grid Smart Grid Research Institute,Beijing 102200,China;Ningbo Institute of Materials Technology&Engineering,Chinese Academy of Sciences,Ningbo 315201,Zhejiang,China;AECC Beijing Institute of Aeronautical Materials,Beijing 100095,China)

机构地区：[1]北京科技大学腐蚀与防护中心,北京100083 [2]国家电网智能电网研究院,北京102200 [3]中国科学院宁波材料技术与工程研究所,浙江宁波315201 [4]中国航发北京航空材料研究院,北京100095

出　　处：《材料工程》2018年第2期105-114,共10页Journal of Materials Engineering

基　　金：国家重点基础研究发展计划项目(2014CB643300);国家自然科学基金项目(51171023);国家材料环境腐蚀平台(2005DKA10400)

摘　　要：利用中性盐雾实验、慢应变速率拉伸实验研究M152和17-4PH高强钢在高Cl^-环境中的应力腐蚀行为和机理。结果表明:M152和17-4PH钢在高Cl^-环境中均有一定的应力腐蚀开裂(SCC)敏感性,且随着前期中性盐雾时间的延长,其伸长率逐渐降低,SCC敏感性逐渐升高;通过扫描电子显微镜对试样的断口和侧边裂纹进行观察比较发现,中性盐雾时间的延长会使M152和17-4PH高强钢的断裂机制由韧性断裂向脆性断裂转变。分析得出M152和17-4PH钢在高Cl^-环境中发生SCC是阳极溶解(AD)和氢脆(HE)的协同作用,Cl^-会加速AD过程。经过不同时间中性盐雾后17-4PH钢的SCC敏感性均比M152钢要高,HE作用也越明显。高Cl^-环境中,17-4PH高强钢相对M152钢更易发生SCC。The stress corrosion cracking(SCC)behavior and mechanism of M152 and 17-4PH high-strength steels in high Cl-environment were studied through neutral salt spray test and slow strain rate tensile(SSRT)test.The result shows that M152 and 17-4PH steels exhibit a certain sensitivity to SCC in Cl-environment,elongations of them both decrease with the increasing time of early neu-tral salt spray test,and the SCC sensitivity gradually increases.Comparing the fracture morphology with lateral crack through SEM,it can be found that the fracture mechanism of M152 and 17-4PH high-strength steels converts ductile fracture to brittle fracture as the extension of neutral salt spray test time.The synergistic effect of anodic dissolution(AD)and hydrogen embrittlement(HE)result in the occurrence of SCC in high Cl-environment,and Cl-can promote the AD process.Due to the obvious effect of HE,17-4PH steel has higher SCC sensitivity than M152 steel with the same time of early neutral salt spray test.17-4PH high-strength steel is more prone to SCC than M152 in high Cl-environment.

关 键 词：高强钢 慢应变速率拉伸 高Cl环境 应力腐蚀开裂 

分 类 号：TG172.5[金属学及工艺—金属表面处理]