摘要
通过JMatPro材料性能模拟软件、扫描电镜、能谱仪和电化学测试等方法研究了显微组织铁素体化对2507双相不锈钢耐点蚀性能的影响机理。结果表明:经1 050~1 250℃保温60 min的固溶处理后,2507双相不锈钢的显微组织发生铁素体化,奥氏体相的吉布斯自由能上升,随固溶温度升高,铁素体相含量增多,铁素体化速率逐渐减小;显微组织铁素体化导致两相中化学元素的含量产生明显变化,即铁素体相中铬、钼含量下降,奥氏体相中镍、氮含量上升;随着耐蚀性较弱的铁素体相含量上升,2507双相不锈钢的钝化膜和蚀孔欧姆压降快速下降,腐蚀电流密度上升,耐点蚀性能快速下降。
The effect of microstructure ferritization on pitting corrosion resistance of 2507 duplex stainless steel was studied by JMatPro material performance simulation software, scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and electrochemical testing. The results show that after the solution treatment at 1 050-1 250 ℃ for 60 min ferritization happened in the microstructure of 2507 duplex stainless steel, resulting in the increase of Gibbs free energy of austenite phase. With the increase of solution treatment temperature, the content of ferrite increased, but the rate of ferritization decreased. The ferritization of microstructure led the chemical element content of two phases change obviously, that is, the content of Cr and Mo of in ferrite phase decreased, while the content of Ni and N in austenite phase increased. When the content of ferrite phase with weak corrosion resistance increased, the resistance of passive film and corrosion hole of 2507 duplex stainless decreased rapidly, the corrosion current density increased, and the pitting corrosion resistance decreased rapidly.
作者
武时会
王晓阳
强华
WU Shihui;WANG Xiaoyang;QIANG Hua(School of Mechanical,Electrical and Information Engineering Chongqing College of Humanities,Science&Technology,Chongqing 401520,China)
出处
《腐蚀与防护》
CAS
北大核心
2022年第5期18-24,67,共8页
Corrosion & Protection
基金
重庆市教委科学技术研究青年项目(KJQN202101801,KJQN202001802)
重庆市教委教学改革项目(183061)
重庆市人文科技学院科学研究项目(CRKZK2021003)。
关键词
2507双相不锈钢
热处理
铁素体化
耐点蚀性能
2507 duplex stainless steel
heat treatment
ferritization
pitting corrosion resistance
