In the present paper, a new generalized strain energy density-based life prediction model was proposed by analyzing the drawbacks of the commonly-used fatigue life prediction criteria. In the proposed model, the critical plane was defined as the maximum shear strain energy density plane with the larger normal strain energy density. A weight index was introduced in this model to take into account the different influences of the normal and shear strain energy components on fatigue life. The maximum normal stress and shear mean stress were both introduced to consider the effects of mean stress. Besides, the maximum normal stress can also be used to account for the reduction of fatigue life under non-proportional loading. The step-by-step procedures were presented to determine the orientation of the critical plane as well as the damage parameters contained in the proposed model. The accuracy and reliability of the proposed model were systematically checked by using about 280 test data through testing 8 kinds of materials under both proportional and non-proportional loadings with zero/non-zero mean stresses. Comparisons with three commonly-used life prediction models showed that the proposed model has highest life prediction accuracy and reliability.

本文通过分析常用疲劳寿命预测准则的不足，提出了一种新的基于广义应变能密度的寿命预测模型。在所提出的模型中，临界平面被定义为最大剪切应变能量密度具有较大法向应变能量密度的平面。该模型中引入了一个权重指数，以考虑法向和剪切应变能分量对疲劳寿命的不同影响。为了考虑平均应力的影响，引入了最大法向应力和平均剪切应力。此外，最大法向应力也可以用来解释非比例载荷下疲劳寿命的减少。提出了分步程序来确定临界平面的方向以及所提出模型中包含的损伤参数。通过在零/非零平均应力的比例和非比例加载下对8种材料进行测试，使用约280个测试数据系统地检验了所提出模型的准确性和可靠性。