A fatigue life estimation method is proposed for the notched specimens under low-velocity repeated impact loadings. The stress concentration effect at the notch root is taken into account by the implementation of the Theory of Critical Distance, and the continuous variation of strain ranges at the critical point due to the plastic strain accumulation is considered by the mean strain modification. The impact fatigue experiment is conducted on the notched plate specimen of material S45C with the pendulum-type test machine, and the comparison with the numerical analysis results indicates that the proposed model gives a satisfactory prediction on the impact fatigue lives.

中文翻译：

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缺口试样在低速冲击下疲劳寿命分析的临界距离模型

针对低速反复冲击载荷下的缺口试样，提出了疲劳寿命估算方法。通过实施“临界距离理论”考虑了在切口根部的应力集中效应，并且通过平均应变修正考虑了由于塑性应变累积而在临界点处应变范围的连续变化。用摆式试验机对材料S45C的缺口板试样进行了冲击疲劳试验，与数值分析结果的比较表明，该模型对冲击疲劳寿命给出了满意的预测。