摘要
Gear teeth in gear transmission systems suffer seriously from fatigue failure during service. In this work, a 2 D double-tooth model was constructed with periodic boundary conditions. The fatigue fracture behavior of gear teeth was analyzed using the extended finite element method(XFEM), with emphases on the impacts of initial crack geometries and cyclic load factors. The results suggested that the shortest fatigue life is expected for 0° orientation cracks initiating at the maximum principal stress. Cracks that initiate closer to the bottom land of gear tooth are relatively safe. Moreover, to evaluate the fatigue load conditions, load ratio, load range, and mean load should be all taken into considerations. Further XFEM simulation for material selection was performed to guide the gear design. Among various material parameters, the material constant C and tensile strength are the most significant ones in determining the fatigue life.
齿轮传动系统主要失效形式是齿牙疲劳断裂。本文作者基于周期性边界条件建立二维双齿模型。采用扩展有限元法(XFEM)对服役过程齿牙的疲劳行为进行分析,重点研究初始裂纹和载荷因素对齿牙疲劳断裂的影响。结果表明,当最大主应力处萌生取向为0°的裂纹时,齿牙疲劳寿命最短,而靠近齿根的裂纹相对安全。同时,评价疲劳载荷情况必须综合考虑载荷比、载荷幅和平均载荷值。进一步针对材料选材开展模拟研究,为齿轮的设计提供指导。模拟结果表明,材料常数C和抗拉强度是影响齿牙疲劳寿命的最重要参数。
基金
Project(2018YFE0306100) supported by the National MCF Energy R&D Program of China
Project supported by the State Key Laboratory of Powder Metallurgy,Central South University,China
作者简介
Corresponding author:Yong JIANG;Tel:+86-731-88836320;E-mail:yjiang@csu.edu.cn.
