固溶处理对2205双相不锈钢组织及钝化膜特性的影响

用不同温度对2205双相不锈钢进行固溶处理,利用定量金相法及硬度法、电化学极化试验、电化学阻抗谱试验的方法研究固溶温度与2205双相不锈钢微观组织和钝化膜特性之间的关系。结果表明,当固溶温度为950 ℃时,有σ相存在,分布于铁素体/奥氏体晶界,当固溶温度为1000 ℃时,σ相消失,铁素体相比例随固溶温度的升高而升高,奥氏体相比例则呈相反规律;电化学试验和阻抗谱试验结果显示,材料在950 ℃时钝化膜稳定性和耐蚀性能最差,在1050 ℃时钝化膜稳定性和耐蚀性能最好。

Effect of solution treatment on microstructure and passivation film properties of 2205 duplex stainless steel

Solid solution treatment of 2205 duplex stainless steel was carried out at different temperatures.The relationship between solid solution temperature and microstructure and passivation film characteristics of 2205 duplex stainless steel was studied by means of quantitative metallographic method,hardness method,electrochemical polarization test and electrochemical impedance spectroscopy.The results show thatσphase exists at 950℃and distributes at ferrite/austenite grain boundaries,but disappears at 1000℃.Ferrite phase ratio increases with the increase of solid solution temperature,while austenite phase ratio shows the opposite rule.The electrochemical and impedance spectroscopy results show that the passivation film has the worst stability and corrosion resistance when solution treated at 950℃,and the passivation film has the best stability and corrosion resistance at 1050℃.