物理短裂纹疲劳扩展的Markov链模拟

Markov Chain Modelling of Physically Fatigue Short Crack Propagation

使用Ｍａｒｋｏｖ链理论，基于１６Ｍｎ钢小试样疲劳裂纹扩展试验，构造了一个物理短裂纹扩展的概率演化模型。该模型对裂纹扩展的循环数分布以及分布的演化过程的模拟，表明了与实验结果良好的吻合程度，从而为物理短裂纹扩展的概率分析及可靠性评价提供了手段。

Based on the experiments on the propagation of physically fatigue short cracks in steel 16Mn, a probabilistic evolutional model of physically fatigue short cracks was constructed by means of Markov chain theory. For a good modelling, a method was employed to transform a non stationary Markov chain into a quasi stationary one. The model was used to simulate the fatigue cycle number distribution and its evoluational process of physically fatigue short cracks in steel 16Mn, and the results from the model showed well agreeable to the data from the experiments. The model provides a tool for fatigue probabilistic analysis and reliability assessments of physically fatigue short cracks.