为满足加工工艺的要求,对轴承套圈锻坯进行了球化退火处理。对球化退火后轴承套圈锻坯表层的显微组织进行分析。结果表明:如果炉气碳势控制不当,在锻坯表面会形成脱碳层;随着炉气碳势逐渐降低,对应生成不同的球化组织,二者之间的对应关系符合扩散定律菲克方程的误差解;结合Fe-Cr-C三元相图,不同炉气碳势会导致碳含量不同;绘制了碳浓度曲线,表层组织的转变符合该曲线的变化规律。

In order to meet the requirements of the processing technology, the bearing ring forging blank was subjected to spheroidizing annealing treatment. The microstructure of the surface layer of bearing ring forging blank after spheroidizing annealing was analyzed. The results show that the decarburization layer would be formed on the surface of forging blank if the carbon potential of furnace gas was not properly controlled. As the furnace carbon potential gas gradually decreased, corresponding to the formation of different spheroidized structures, the corresponding relationship between the two conforms to the error solution of the Fick equation of the diffusion law. Combined with the Fe-Cr-C ternary phase diagram, different furnace gas carbon potential would lead to different carbon content. A carbon concentration curve was drawn and the transformation of the surface structure conformed to the change rule of the curve.