疲劳裂纹扩展参数研究

A PARAMETER STUDY OF FATIGUE CRACK PROPAGATION

在大量拉－压超载实验的基础上导出考虑拉－压超载中压缩载荷影响的参数———超载截止比γＳＲ的计算式，并提出简单超载截止比γＳＯ的实验测定方法。将参数γＳＲ用于裂纹扩展寿命预测模型。

Based on plenty of tensile-compressive overload test,a formula of overload shut-off ratio γ SR ,the parameter which takes account of reducing overload retardation effect by compressive load,is proposed.For delermining the value of overload shut-off ratio γ SO of single overload,a test method is suggested here as well.It is shown that the prediction of crack propagation life with the parameter γ SR involved in is well correlated with the test results of random load spectra.