本文采用光学显微镜、显微硬度等分析手段对某钢厂生产的GCr15轴承钢在不同冷却速度下的奥氏体相变规律进行了研究。结果表明：发生珠光体相变的临界冷却速度约为3℃/s，当温度降至约200℃时，发生马氏体转变。冷却速度小于5℃/s时，会产生较严重的网状碳化物，随冷却速度的提高，网状碳化物析出减少，珠光体相变温度降低。
The Austenite phase transformation law of GCr15 bearing steel with different processes is studied by means of optical microscope and hardness tester. The experimental results show that: the critical cooling rate of pearlite phase transformation is about 3？C/s and the Martensite transfor-mation starts when the temperature drops at about 200？C. There will be a serious precipitation of net carbide when the cooling rate is less than 5？C/s, and with the increase of cooling rate, the pearlite phase transformation temperature becomes lower and the precipitation of net carbide decreases.
