Journal of South China University of Technology(Natural Science Edition) ›› 2025, Vol. 53 ›› Issue (7): 50-59.doi: 10.12141/j.issn.1000-565X.240278

• Mechanical Engineering • Previous Articles     Next Articles

A Contact Fatigue Assessment Model for Gears Considering Residual Stress and Inhomogeneities

LIU Yi1,2, SUN Linlin3, YANG Wenhan1, GUO Hui1, HOU Shengwen2, LIU Geng1   

  1. 1.School of Mechanical Engineering,Northwestern Polytechnical University,Xi’an 710072,Shaanxi,China
    2.Key Laboratory of Gear Transmission of Shaanxi Province,Shaanxi Fast Auto Drive Group Co. ,Ltd. ,Xi’an 710119,Shaanxi,China
    3.Key Laboratory of Road Construction Technology and Equipment of the Ministry of Education,Chang’an University,Xi’an 710064,Shaanxi,China
  • Received:2024-06-04 Online:2025-07-25 Published:2025-02-21
  • About author:刘义(1978—),男,博士生,正高级工程师,主要从事齿轮设计与制造研究。E-mail: liuyi@fastgroup.cn
  • Supported by:
    the National Natural Science Foundation of China(52205048);the Key Research and Development Program of Shaanxi Province(2023GXLH-087)

Abstract:

Gear surface treatment techniques such as gear grinding, shot peening and surface finishing may generate residual stress inside the material. Meanwhile, inhomogeneities are inevitably present in metal materials. Both residual stress and inhomogeneities have a significant impact on the contact fatigue life of gears. In order to effectively assess the contact fatigue risk of gears, this paper proposes a numerical model that comprehensively considers the combined effects of residual stress and inhomogeneities. This model uses the equivalent inclusion method to convert the inhomogeneities inside the gear into inclusions containing eigenstrains, and considers the coupling effect of inhomogeneities and residual stress in the displacement equation. During the research process, the stress distribution under the joint action of residual stress and inhomogeneities is computed, and the model is verified using the finite element method. The equivalent stress is calculated using Dang Van criterion, which is then incorporated into the Lundberg-Palmgren life model to find the minimum number of cycles, and the influence laws of residual stress and inhomogeneities on the gear’s contact fatigue life are analyzed. Analytical results show that inhomogeneities have a much greater influence on the contact fatigue life of gears than residual stress, and they predominantly determine the earliest meshing point of contact fatigue on the gear; and that, under the combined effects of residual tensile stress and inhomogeneities, the maximum stress in the sub-surface layer increases and shifts towards the material surface, making the gear more prone to contact fatigue.

Key words: gear, contact fatigue, residual stress, inhomogeneous material, risk assessment, Dang Van criterion

CLC Number: