摘要
采用光学显微镜、扫描电镜、洛氏硬度计等实验设备,通过高温回火+等温球化处理工艺研究了ZGCr17Ni2马氏体不锈钢的软化行为,分析了组织、硬度变化规律。结果表明:回火温度由600℃逐步提高至700℃,组织由铸态的珠光体+马氏体+残余奥氏体+莱氏体+碳化物转变为珠光体+回火索氏体+不稳定残余奥氏体+莱氏体+碳化物,硬度由铸态时的HRC47逐步降低至HRC29。随后进行的等温球化使其基体珠光体进一步球化,但对硬度影响不大。最佳软化处理工艺为:高温回火650℃+2 h,等温球化760℃+2 h-700℃+2 h,炉冷。其组织为粒状珠光体+莱氏体+碳化物,硬度为HRC27。
The softening behavior of ZG5 Cr17 Ni2 martensitic stainless steel was studied by high temperature tempering + isothermal spheroidization. The change rules of microstructure and hardness were analyzed by using optical microscope, scanning electron microscope and Rockwell hardness tester. The results show that, as ZG5 Cr17 Ni2 martensitic stainless steel was tempered and the temperature was gradually increased from 600 ℃to 700 ℃, the microstructure transformed from pearlite + martensite + retained austenite + ledeburite+ carbide in the as-cast state into pearlite + tempered sorbite + unstable retained austenite + ledeburite + carbide in the tempering state;the hardness was reduced to HRC29 from HRC47 in the as-cast state. Subsequent isothermal spheroidization made the pearlite spheroidization further and had little effect on hardness. Therefore, the best softening process of ZG5 Cr17 Ni2 martensitic stainless steel is: tempering at 650 ℃ for 2 h, isothermal spheroidizing at 760 ℃ for 2 h and subsequently rapidly cooling to 700 ℃ and holding for 2 h, furnace cooling. The microstructure consists of spheroidized pearlite + ledeburite + carbide, and the hardness is HRC27.
作者
索忠源
王鑫
王文革
张志浩
王毅坚
SUO Zhong-yuan;WANG Xin;WANG Wen-ge;ZHANG Zhi-hao;WANG Yi-jian(College of Mechanical and Electrical Engineering,Jilin Institute of Chemical Technology,Jilin 132022,Jilin,China)
出处
《铸造》
CAS
北大核心
2019年第10期1094-1097,共4页
Foundry
基金
吉林市科技局项目（20166020）
吉林化工学院项目（2017036）
