目的 研究热和相变应变各自在渗碳淬火畸变中的作用，分析渗碳淬火工艺对齿轮合金钢畸变的影响。方法 通过考虑相变和不考虑相变两种模型，对齿轮合金钢17CrNiMo6 C形开口畸变试样渗碳淬火的畸变机理和变形过程进行数值模拟，并设计正交试验，量化工艺参数对畸变的影响程度，最后利用渗碳淬火实验测定表面含碳量和畸变量，验证分析结果。结果 初始工艺下热应变约为相变应变的2倍。正交试验各工艺参数的F比结果从大到小顺序为：渗碳温度（1.74）、淬火温度（1.546）、碳势（1.448）、预热温度（0.603）和油温（0.473）。优化工艺参数为：渗碳温度880 ℃，淬火温度790 ℃，预热温度500 ℃，碳势0.8%，油温80 ℃。优化后畸变率减少了28.5%，畸变分析结果与实验结果对应较好。结论 由热膨胀引起的热应变对试样的畸变占据主动，抵消并超过相变应变，渗碳温度、碳势和淬火温度对齿轮合金钢畸变影响较大。

The work aims to study the respective effect of thermal and phase transformation strain on carburizing quenching distortion, and analyze the influence of carburizing and quenching process on the distortion of gear alloy steel. The mechanism and deformation process of carburizing-quenching distortion on the C-shaped opening distortion sample made of gear alloy steel 17CrNiMo6 were numerically simulated with/without phase transformation consideration. The effect of the carburizing and quenching process on the distortion was quantified by orthogonal experiment. In order to verify the analysis results, the carbon content of the surface and distortion were determined by carburizing-quenching experiment. In the initial process, the thermal strain was about 2 times of the phase transformation strain. The order of F ratio of all process parameters in the orthogonal experiment from large to small was carburizing temperature (1.74), quenching temperature (1.546), carbon potential (1.448), preheating temperature (0.603) and oil temperature (0.473). The optimized process parameters were carburizing temperature 880 ℃, quenching temperature 790 ℃, preheating temperature 500 ℃, carbon potential 0.8%, and oil temperature 80 ℃. After optimization, the distortion rate was reduced by 28.5% and the distortion analysis results corresponded well with the experimental results. The thermal strain caused by thermal expansion takes the initiative to distort the sample and counteracts and exceeds the transformation strain. Carburizing temperature, carbon content and quenching temperature have a greater effect on distortion of gear alloy.