模拟深海环境中阴极极化对1000 MPa级高强钢氢脆敏感性的影响  

Effect of Cathodic Potentials on Hydrogen Embrittlement of 1000 MPa Grade High Strength Steel in Simulated Deep-sea Environment

作　　者：周宇 张海兵[2] 杜敏[1] 马力[2] ZHOU Yu;ZHANG Haibing;DU Min;MA Li(College of Chemistry and Chemical Engineering,Ocean University of China,Qingdao 266100,China;State Key Laboratory for Marine Corrosion and Protection,Luoyang Ship Material Research Institute(LSMRI),Qingdao 266237,China)

机构地区：[1]中国海洋大学化学化工学院,青岛266100 [2]中国船舶重工集团公司第七二五研究所海洋腐蚀与防护重点实验室,青岛266237

出　　处：《中国腐蚀与防护学报》2020年第5期409-415,共7页Journal of Chinese Society For Corrosion and Protection

摘　　要：通过实验室模拟800 m深海环境及浅海环境,采用动电位极化法、慢应变速率拉伸实验(SSRT)并结合扫描电镜(SEM)观察断口显微组织研究1000 MPa级高强钢的氢脆敏感性。结果表明,在模拟800 m深海环境中高强钢试样的零电流电位为-708 m V,析氢电位约为-1000 mV;在浅海环境中的零电流电位为-645 mV,析氢电位约为-910 mV。随着阴极极化电位的负移,模拟800 m深海环境及浅海环境实验高强钢均表现出韧性降低、脆性增加、氢脆敏感性增强的现象。模拟800 m深海环境中,极化电位正于-900 mV时,其氢脆系数小于25%,处于安全区;极化电位为-1000 mV时,氢脆系数接近50%,处于脆断区。The hydrogen embrittlement of a 1000 MPa grade high strength steel in simulated 800 m deep-sea environment and shallow sea environment by open circuit potential or applied various cathodic potentials was comparatively studied by means of slow strain rate tensile tests,potentiodynamic polarization measurements and SEM.Results showed that for the high strength steel,the open circuit potential was approximately-708 mV(vs Ag/AgCl/seawater)and the hydrogen evolution potentials was about-1000 mV(vs Ag/AgCl/seawater)in the simulated 800 m deep-sea environment.While the open circuit potential was approximately-645 mV(vs Ag/AgCl/seawater)and the hydrogen evolution potentials was about-910 mV(vs Ag/AgCl/seawater)in the shallow sea environment.With the cathodic polarization potential dropped from-800 mV to-1000 mV,the toughness of the tested high-strength steel was reduced,i.e.the brittleness was increased,implying that the susceptibility to hydrogen embitterment was enhanced.When the polarization potential was higher than-900 m V,the hydrogen embrittlement coefficient of high-strength steel was less than 25%,namely,the steel is still in the safe range.When the polarization potential reached further to-1000 mV,the hydrogen embrittlement coefficient increased to about50%,which was in the brittle fracture range for the steel.

关 键 词：模拟深海环境 高强钢 氢脆 阴极极化 慢应变速率拉伸 

分 类 号：TG174.3[金属学及工艺—金属表面处理]