关键词: 疲劳寿命；S-N曲线；ε-N曲线；疲劳极限；韧性

Abstract:

The characteristics of fatigue life curve of materials in three stages of fatigue life were analyzed and then a model with three parameters was presented to describe the fatigue life curve of materials in the whole region. Three parameters quantitatively describe the fatigue limit, the toughness and the characteristic fatigue life of material in the model and a convenient method to obtain the parameters was mentioned. The model can describe the strain-life curve as well as stress-life curve of materials by the normalized loading. Nineteen sets of experimental data of metals and composites were employed to verify the model, and the results show that the model is capable to describe the fatigue life curve of materials in whole region.

Key words: fatigue life, S-N curve;ε-N curve, fatigue limit, toughness