【摘要】 考虑到应力比对疲劳裂纹扩展速率的影响及裂纹扩展的分散性,在Paris公式基础上,提出了一种考虑应力比的疲劳裂纹扩展概率模型;运用非线性函数线性化原理给出概率模型参数的求解方法;通过该概率模型和曲面,可从宏观上把握应力比对裂纹扩展的影响规律及得到任意应力比下的概率疲劳裂纹扩展速率曲线;对30CrMnSiNi2A钢试验数据的处理及分析验证了该模型的有效性和实用性.更多还原

【Abstract】 Based on Paris formula,a fatigue crack growth probability model was established in consideration of the influence of stress ratio on fatigue crack growth rate and the dispersion of fatigue crack growth.The parameters of this probability model were estimated by using the principle of no-linear function linearization.Through this probability model and surfaces,the regulations of the effect of stress ratio on fatigue crack growth can be mastered and the probability fatigue crack growth rate curves at any stress ratios can be obtained.Availability and feasibility are indicated by an analysis of the 30CrMnSiNi2A steel test data.更多还原