球化退火工艺对轴承钢线材碳化物的影响
Effect of Spheroidizing Annealing Process on Carbide of Bearing Steel Wire

为了研究不同球化退火工艺对GCr15轴承钢线材碳化物的影响，借助显微电镜、光学图像处理软件对4种不同退火工艺处理后碳化物的数量、尺寸、显微硬度进行了分析。结果表明：当退火工艺在固溶温度800℃、保温1 h后，以25℃/h冷却速率随炉冷却到700℃后保温1 h，而后以15℃/h冷却速率随炉冷却到650℃随后空冷时，碳化物颗粒最为细小，平均尺寸为0.23 um，颗粒最为圆整。当固溶温度处于780℃~800℃区间时，固溶温度越高，球化效果越好，保温时间越长，退火后碳化物颗粒越细小。退火工艺对钢种的显微硬度有一定影响，但程度有限。
In order to study the influence of different spheroidizing annealing processes on the carbide of GCr15 bearing steel wire, the quantity, size and microhardness of carbides treated by four different annealing processes were analyzed by means of micro-electron microscopy and optical image processing software. The results show that when the solid solution temperature of annealing pro-cess was 800？C and heat preservation 1 h with 25？C/h cooling rate with furnace cooling to 700？C, after1 h with 15？C/h cooling rate with furnace cooling to 650？C, and then air cooling; the particles of carbide are the finest with an average size of 0.23 um and the most rounded. When the solid so-lution temperature is in the range of 780？C~800？C, the higher the solid solution temperature, the better the spheroidization effect; the longer the holding time, the finer the carbide particles after annealing. The annealing process has a certain effect on the microhardness of the steel, but to a limited extent.