Cr和Ni对低碳合金钢微观结构和耐蚀性的影响  

Effects of Cr and Ni on the Microstructure and Corrosion Resistance of Low Carbon Alloy Steel

作　　者：王丹 钟庆东[2] WANG Dan;ZHONG Qing-dong(College of Advanced Vocational Technical,Shanghai University of Engineering Science,Shanghai 200437,China;School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China)

机构地区：[1]上海工程技术大学高等职业技术学院,上海200437 [2]上海大学材料科学与工程学院,上海200444

出　　处：《材料保护》2023年第6期63-74,共12页Materials Protection

基　　金：上海工程技术大学高职学院科研基金重点项目(GZ21⁃1)资助。

摘　　要：为探究Cr和Ni含量对低碳合金钢组织和性能的叠加促进效应,通过SEM、XRD、硬度测试、电化学测试、浸泡试验及XPS测试等方法研究了Cr和Ni含量对低碳合金钢微观结构及其在模拟海水(3.5%NaCl溶液)中耐蚀性的影响。结果表明:同时增加Cr和Ni含量能显著促进钢中形成更多尺寸细小的碳化物Cr_(3)C_(2),进而促进晶粒尺寸减小、马氏体组织细化及增加硬度;同时增加钢中Cr和Ni的含量对钢在模拟海水环境中热力学稳定性、动力学稳定性、抵抗腐蚀损伤能力的提升均大于单独增加Cr或Ni含量的情况;增加钢中Cr的含量能提高NiFe_(2)O_(4)、FeO在腐蚀产物中的占比,增加钢中Ni的含量能提高腐蚀产物中FeCr_(2)O_(4)、FeO的占比,且同时增加钢中的Cr和Ni含量对提高NiFe_(2)O_(4)、FeCr_(2)O_(4)、FeO等占比的促进效果高于单独增加Cr或Ni含量的情况;NiFe_(2)O_(4)、FeCr_(2)O_(4)、FeO越多,腐蚀产物致密性越高,对基体的保护性越好,钢的耐蚀性越高。同时增加钢中的Cr和Ni含量对低碳合金钢微观结构和耐蚀性存在叠加促进效应。For exploring the superposition⁃promotion effects of Cr and Ni contents on the structure and properties of low carbon alloy steel,the effects of Cr and Ni on the microstructure and corrosion resistance of low carbon alloy steel in the simulated seawater(3.5%NaCl solution)were investigated by SEM,XRD,hardness tests,electrochemical tests,immersion tests and XPS analysis.Results showed that simultaneously increasing the content of Cr and Ni could significantly promote the formation of more fine sized carbides Cr_(3)C_(2)in steel,which further promoted the decrease of the grain size,the refinement of the martensite and the increase of the hardness.Simultaneously increasing the content of Cr and Ni in steel improved the thermodynamic stability,kinetic stability,and resistance to corrosion damage in the simulated seawater environment more than increasing the Cr or Ni content alone.Moreover,the increase of Cr in the steel could increase the proportion of NiFe_(2)O_(4)and FeO in the corrosion products,the increase of Ni could increase the proportion of FeCr_(2)O_(4)and FeO in corrosion products,simultaneously increasing the Cr and Ni content in steel has a higher promotion effect on increasing the percentage of NiFe_(2)O_(4),FeCr_(2)O_(4)and FeO,etc.than increasing the Cr or Ni content alone.Besides,the more NiFe_(2)O_(4),FeCr_(2)O_(4)and FeO,the higher the densification of corrosion products,the better the protection for the substrate,and the higher the corrosion resistance of the steel.Therefore,simultaneously increasing the content of Cr and Ni had superposition⁃promotion effects on the microstructure and corrosion resistance of low carbon alloy steel.

关 键 词：CR NI 低碳合金钢 微观结构 耐蚀性 叠加促进效应 

分 类 号：TG172[金属学及工艺—金属表面处理]