GCr15轴承钢先共析渗碳体的相变规律

Phase transformation behavior of proeutectoid cementite in GCr15 bearing steel

由于相变过程中转变量较少,所以难以通过膨胀法测定轴承钢先共析渗碳体的相变温度。本文采用Gleeble3800热模拟实验机,研究在不同冷速下GCr15轴承钢的相变规律,首先通过膨胀法测得珠光体的相变温度区间约为550~700℃,以此为基础,采用金相法研究了先共析渗碳体的相变温度范围约为700~900℃,绘制出GCr15轴承钢完整的相变温度曲线。在此基础上,讨论了采用两阶段冷却工艺抑制先共析渗碳体形成的方案,为现场生产控制GCr15轴承钢中的网状碳化物提供了依据。

It is difficult to measure the phase transition temperature of proeutectoid cementite of bearing steel by expansion method due to the small amount of transformation in the process of phase transformation. In this paper, Gleeble3800 thermal simulation experiment machine was used to study the phase transformation behavior of GCr15 bearing steel at different cooling rates. Firstly, the phase transition temperature range of pearlite is about 550-700 ℃ measured by expansion method. Based on this, the transformation temperature range of proeutectoid cementite is about 700-900 ℃ obtained by metallographic method, and the complete phase transition temperature curve of the GCr15 bearing steel is drawn. On this basis, the scheme of suppressing the formation of proeutectoid cementite by two-stage cooling process is discussed, which provides a basis for on-site production control of network carbide of the GCr15 bearing steel.