Prediction and Evaluation of Fatigue Strength via Mechanical Behavior of Materials

基於材料力學性能的疲勞強度預測與評估

劉新田(Xin-Tian Liu) ； 王海傑(Hai-Jie Wang) ； 楊小兵(Xiao-Bing Yang) ； 賴家鳳(Jia-Feng Lai)

《中國機械工程學刊》 43卷3期 (2022/06) Pp. 229-238

摘要

Besides stress, the fatigue failure of part is also affected by the fatigue strength of materials. Therefore, it is necessary to predict the fatigue strength of materials before analyzing fatigue life. Considering the factors with uncertainty that affect the fatigue strength, the modified factors of fatigue are determined, and the stochastic fatigue strength is predicted. Among them, the distribution type and parameters of roughness factor are analyzed by improving Bootstrap method, which provides a method to analyze small samples. Moreover, the S-N curve cluster that characterizes the fatigue property is obtained, which provides a basis for fatigue life prediction.

關鍵字

fatigue strength ； mechanical behavior ； low alloy steel ； small samples

並列摘要

零件的疲勞失效除受應力影響外，還受資料疲勞強度的影響。囙此，在進行疲勞壽命分析之前，有必要對資料的疲勞強度進行預測。考慮影響疲勞強度的不確定性因素，確定了疲勞修正係數，並對隨機疲勞強度進行了預測。其中，通過改進Bootstrap方法分析了粗糙度因數的分佈類型和參數，為小樣本分析提供了一種方法。得到了表徵疲勞效能的S-N曲線簇，為疲勞壽命預測提供了依據。