含夹杂物轴承钢中裂纹的萌生与扩展

针对轴承钢中夹杂物周围应力集中导致的疲劳剥落,建立了一种结合连续损伤力学的内聚力模型,用于模拟滚动接触循环加载下的裂纹萌生与扩展。基于内聚力模型的损伤起始准则和损伤演化规律,利用VUMAT子程序结合连续损伤力学构造了新的损伤演化方式,实现循环加载下的损伤累积,建立了基于内聚力模型的疲劳损伤累积失效模型,对含夹杂物模型的疲劳裂纹萌生与扩展进行了模拟,并研究了载荷条件和接触区摩擦因数对裂纹萌生与扩展以及疲劳寿命的影响。研究结果揭示了微观裂纹的萌生与扩展过程,为认识滚动接触疲劳提供了基础。

Crack Initiation and Propagation in Bearing Steel Containing Inclusions

Aimed at fatigue spalling caused by stress concentration around inclusions in bearing steel,a cohesive model combined with continuous damage mechanics is developed to simulate the crack initiation and propagation under rolling contact cyclic loading.Based on damage initiation criterion and damage evolution law of cohesive model,a new damage evolution mode is constructed by using VUMAT subroutine combined with continuous damage mechanics to realize the damage accumulation under cyclic loading.A fatigue damage accumulation failure model based on cohesive model is established to simulate the fatigue crack initiation and propagation of model containing inclusions,and the effects of loading conditions and friction coefficient in contact area on crack initiation and propagation and fatigue life are investigated.The results reveal the processes of initiation and propagation of micro cracks,and provide a base for understanding of rolling contact fatigue.