摘  要：根據試驗要求，對葉片在樣本較少情況下測定其疲勞極限σ-1和S-N曲線。通過振動疲勞試驗的方法進行研究，試驗采用升降法選擇所施加振動應力的水平，采用異方差回歸分析方法進行疲勞試驗數據的分析。最后獲得葉片材料的均值S-N曲線和置信度為95%、可靠度為99.9%的P-S-N曲線，并得到各自曲線上的疲勞極限σ-1。此方法保證試驗的順利進行并且具有較高的可靠性，對于小樣本測定材料的S-N曲線具有較好的實用價值。

關鍵詞：疲勞極限；小子樣測試；S-N曲線；升降法；異方差回歸分析方法

文獻標志碼：A       文章編號：1674-5124（2015）12-0124-04

Studies on small sample test method for blade S-N curve

ZHANG Bing1，2，　CHEN Liwei1， CHEN Yongxiang1， YAN Xudong2， ZHAO Shuaishuai2

（1. Beijing Institute of Structure and Environment Engineering，Beijing 100076，China；

2. Tianjin Aero-space Relia Technology Co.，Ltd.，Tianjin 300462，China）

Abstract: To determine the fatigue limit σ-1 and S-N curve of blades with few small samples as the test requirements. Vibration fatigue test， that is， the level of vibration stress was fixed via up-down method and the test data was analyzed through variance regression. The S-N curve of mean value and P-S-N curve with 95%-confidence coefficient and 99.9%-reliability of blade materials have been obtained， so as the fatigue limit σ-1 of each curve. The method ensures the smoothness and reliability of the test and has a guiding significance in determining the S-N curve of materials through small sample test.

Keywords: fatigue limit； small sample test； S-N curve； the up and down method； the variance regression analysis method