GCr15轴承钢中渗碳体的奥氏体化行为研究
Study on Austenitizing Behaviors of Cementite in GCr15 Bearing Steel
马宝国1,2, 杨洪波1, 朱伏先1, 刘相华1
点击:3331次 下载:0次
作者单位:1. 东北大学 轧制技术及连轧自动化国家重点实验室, 辽宁 沈阳 110004; 2. 宝山钢铁股份有限公司 特殊钢分公司, 上海 200940
中文关键字:GCr15钢; 渗碳体; 奥氏体化; 扩散
英文关键字:GCr15 steel; cementite; austenitizing; diffusion
中文摘要:利用光学显微镜、扫描电镜(SEM)、维氏硬度计以及thermo-calc和photoshop软件对经不同温度奥氏体化、淬火后的GCr15轴承钢试样的显微组织进行了分析研究。结果表明:720~750 ℃奥氏体化时,碳原子进行短程扩散,几乎无奥氏体生成;755 ℃为奥氏体化的转折点,碳原子进行长程扩散,奥氏体出现;奥氏体化温度为780 ℃时,不但珠光体中的渗碳体全部粒化,先共析渗碳体也溶解碎断,剩余渗碳体以细小弥散的颗粒状分布在奥氏体基体中。
英文摘要:The microstructure of GCr15 bearing steel samples austenitized and quenched at different temperature was studied with optical microscopy, SEM, Vickers hardness tester and software of thermo-calc and photoshop. The results show that carbon atoms diffuse in short distance and no austenite occurs when the testing steel is austenitized at 720~750 ℃; they diffuse in long distance and austenite occurs at 755℃ which is the turning point of austenitizing temperature. When the testing steel is austenitized at 780 ℃, not only all the cementite in pearlite is granulated, but also the pro-eutectoid cementite is dissolved and broken, and the residual cementite particles are small and dispersed in austenite matrix.