The abilities of resisting the incubation of fatigue crack in ast101a and alti101a were tested with the high - cycle fatigue method . a method combining the maximum likelihood estimation method with the correlation coefficient method was suggested to analyze the fatigue life experimental data some of which were incomplete . the s - n curve and p - s - n curves were presented , and the influence of the loading history and the defects in specimen on fatigue life was discussed 通过高周疲劳测试方法研究了ast101a和alti101a抵抗疲劳裂纹萌生的性能，把最大似然法和相关系数法结合起来处理不完全疲劳寿命数据，给出了ast101a的s ? n曲线、 p ? s ? n曲线和疲劳极限，讨论了加载历史、缺陷等对疲劳寿命的影响。
There are two kinds of means to strengthen the fatigue resistance : quenching combining the rolling and nitriding combining the rolling . according to the test the second mean is instability , so the next test are all quenching . structure of crankshaft influence the fatigue resistance , too , the fatigue resistance is damaged by groove at journal circumferentially and 本文重点分析研究了滚压过程中工艺参数对曲轴疲劳极限的影响,在滚压过程中引入了残余应力的预估计,从而建立了最佳滚压力值的数学模型,并对最佳滚压力进行了理论计算以及试验验证。
Second , the random variables in reliability analysis of the steel rail are discussed . these random variables include the wheel load , the stiffness of the rubber pad and the bed , the temperature stress and the fatigue ultimate strength of the steel rail . and their probability distributions and parameters are discussed thoroughly 其次，对钢轨可靠度分析中涉及的随机变量如轮载力、轨下胶垫刚度、道床路基联合刚度、温度应力及钢轨疲劳极限强度的概率分布类型和统计特征进行了详细讨论。
It achieves full test automation from calibrating , running , failure diagnosis and data processing , which establish it an intelligent test system . in the software , a curve fitting program which based on the system ' s principle which can greatly improve the calibration precision and a safl mathematical statistics program for the test data are made 在试验系统软件设计上，结合试验机原理，采用基于原型函数的动态标定数据曲线拟合提高了载荷标定的精度；通过对比各种曲轴试验数据的处理方法，同时考虑在实际运用中的效果，计算机统计采用了疲劳极限统计分析( safl )法。
