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本文运用损伤力学方法对涡轮盘试件榫槽在蠕变和疲劳交互作用下的裂纹起始寿命与裂纹扩展寿命进行了分析研究。榫槽的非线性损伤累积模型是由修正的Ｃｈａｂｏｃｈｅ′ｓ低循环疲劳损伤模型和改进的Ｋａｃｈａｎｏｖ′ｓ蠕变损伤模型综合形成的。在此基础上建立了疲劳和蠕变交互作用下裂纹扩展计算模型。从理论分析计算与试验结果的一致性，说明所建模型的正确性。采用损伤有限元素法，以有限元网格尺寸模拟损伤裂纹长度。从试件榫槽的裂纹扩展计算分析中，提出裂纹起始方向和裂纹扩展方向判断准则，并通过计算检验了此准则的正确性。文中所建立的基本理论，计算方法及结果分析在工程实际中具有一定使用价值。
In this paper, the crack initiation life and crack propagation life under the creep and fatigue interaction of the turbine disk specimen tongue and groove are analyzed using the damage mechanics method. The nonlinear damage cumulative model of tongue and groove is formed by the modified Chaboche’s low cycle fatigue damage model and the improved Kachanov’s creep damage model. Based on this, a crack growth calculation model under the interaction of fatigue and creep was established. From the theoretical analysis and calculation of the consistency of the experimental results, indicating the correctness of the model. The finite element method of damage was used to simulate the damage crack length with finite element mesh size. From the calculation and analysis of the crack propagation in the mortise and tenon groove, the judgment criteria of crack initiation direction and crack propagation direction are proposed. The correctness of this criterion is verified by calculation. The basic theory, calculation method and result analysis established in this article have certain use value in engineering practice.