热处理工艺对5Cr钢力学性能和耐蚀性能的影响

Effect of heat treatment process on mechanical properties and corrosion resistance of 5Cr steel

利用光学显微镜、拉伸及冲击试验机等仪器研究了不同热处理工艺对5Cr钢组织和力学性能的影响,利用高温高压反应釜模拟腐蚀过程,并结合电化学测试对比分析了热轧态和调质态钢的耐腐蚀性能。结果表明:5Cr钢经淬火+回火处理后,组织中碳化物弥散析出,具有较高的强度和良好的塑、韧性。热轧态钢的腐蚀速率为0.188 mm/a,调质态钢为0.158 mm/a。调质态钢中作为阴极的碳化物(Fe_(3)C)少且均匀弥散分布,组织自腐蚀电位较高,腐蚀电流密度较低,电偶腐蚀程度较浅,耐腐蚀性能较好。

Effect of heat treatment process on microstructure and mechanical properties of the 5Cr steel was studied by using optical microscopes,tensile and impact testing machines and other instruments.The corrosion process of 5Cr steel was simulated and the resistance of hot rolled and quenched+tempered steels was compared and analyzed by using high temperature and high pressure reactors and combing with electrochemical tests.The results show that after quenching and tempering treatment,the 5Cr steel has carbides dispersed and precipitated in the structure and has high strength and good plasticity and toughness.The corrosion rate of hot rolled steel is 0.188 mm/a,and that of quenched+tempered steel is 0.158 mm/a.In the quenched+tempered steel,the carbide(Fe_(3)C)as the cathode is less and uniformly dispersed,the self-corrosion potential is higher and the corrosion current density is lower of the structure,the degree of galvanic corrosion is shallow,and the corrosion resistance is better.