热处理工艺对高铬铸铁轧辊组织与性能的影响

Effect of Heat Treatment Process on the Structure and Performance of High Chromium Cast Iron Roll

实验室利用热处理炉进行高铬铸铁轧辊热处理工艺模拟试验;利用金相显微镜、扫面电镜、洛氏硬度计测试分析了热处理过程中微观组织变化、碳化物溶解析出行为和硬度分布情况。结果表明:高铬铸铁在900℃~1050℃,随着淬火温度的升高,碳化物由板条状转变为块状,硬度呈现先上升后下降的趋势,在1000℃淬火后硬度为65.4 HRC;高铬铸铁在1000℃淬火,350℃~550℃回火,残余奥氏体逐渐转变为马氏体,随着回火温度的升高,马氏体中析出碳化物并聚集长大,硬度呈现先上升后下降的趋势,在500℃回火硬度为63.2HRC.

The simulation test of high chromium cast iron roll heat treatment process was carried out in the laboratory using heat treatment furnace.The microstructure changes,carbide dissolution behavior and hardness distribution during the heat treatment were analyzed by means of metallographic microscope,scanning electron microscope and Rockwell hardness tester.The results showed that the carbide changed from strip to block with the increase of quenching temperature at 900℃~1050℃.The hardness first increased and then decreased,after quenching at 1000℃,the hardness is 65.4 HRC.After quenching at 1000℃and tempering at 350℃~550℃,the residual austenite gradually changed into martensite.With the increase of tempering temperature,carbides were precipitated in martensite and grew up,and the hardness first increased and then decreased.The hardness was 63.2 HRC at 500℃.