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研究了ＧＣｒ１５钢淬火不同温度回火后扭转流变硬化行为、组织和强度的关系。研究表明，在双对数坐标上硬化曲线呈现多ｎ行为。在低于２５０℃回火，随回火温度降低，诸ｎ值增大的原因很多，但残余奥氏体及其塑变诱导相变强化效应在其中起着主要作用。在高温回火范围，随回火温度降低，诸ｎ值减小的原因与渗碳体质点间距，即位错运动平均自由程（ＭＦＰ）有关。尽管宏观扭转断口有正断和切断之分，但微观断口均为韧窝，这表明塑变和硬化在断裂过程中起着重要作用。据此，可借助τ（０．３）、γｋ和ｎｌ值的变化分析τｋ值随回火温度变化的规律。
The relationship between the rheological hardening behavior and microstructure and strength of GCr15 steel after quenching at different temperatures was studied. Studies have shown that hardening curves show multiple n behavior in double logarithmic coordinates. There are many reasons why the value of n increases when the temperature is lower than 250 ℃ and then decreases with the tempering temperature. However, the residual austenite and its plastic deformation-induced phase transformation strengthening effect play a major role. In the high-temperature tempering range, as the tempering temperature decreases, the reason for the decrease in n values is related to the spacing of cementite spots, ie, the mean free path of dislocation motion (MFP). Although the macroscopically reversed fracture has a positive and a negative fracture, the microscopic fracture is dimple, indicating that plastic deformation and hardening play an important role in the fracture process. Accordingly, the change of τk value with tempering temperature can be analyzed by the changes of τ (0.3), γk and nl values.