高速动车组齿轮副齿根裂纹应力强度因子数值计算

Numerical Calculation of Stress Intensity Factor of Tooth Root Crack in the High-speed EMU Gear

为研究高速动车组齿轮的齿根裂纹的应力强度因子,结合有限元法和作图法确定了裂纹萌生位置。基于线弹性断裂力学理论,以Abaqus为工具,研究了齿根初始裂纹前缘不同节点处的应力强度因子大小及变化规律,通过对比,确定Ⅰ型应力强度因子在裂纹扩展中占主导地位;在此研究的基础上,探讨了Ⅰ型应力强度因子随载荷、裂纹半径、裂纹形状等因素的变化规律。结果表明,载荷对Ⅰ型应力强度因子大小影响最为显著且呈线性关系;裂纹形状对Ⅰ型应力强度因子在裂纹前缘的分布规律影响十分明显。

In order to research the stress intensity factor of tooth root of the high - speed EMU gear, the location of crack initiation is determined by combining the finite element method and mapping method. The stress intensity factor of the different nodes of the initial crack tip of the tooth root is calculated by Abaqus based on the theory of linear elastic fracture mechanics, then by contrast, the type I stress intensity factor is dominant in the crack propagation. Based on the obtained result, the influence of load magnitude, crack radius and crack shape on the mode I stress intensity factor is discussed. The results indicate that the influence of load magnitude on the mode I stress intensity factor is obvious and linear. The influence of crack shape on the distri- bution of mode I stress intensity factor in the crack front is very obvious.