Study on the contact fatigue prediction model of carburized and quenched spur gears with multiaxial stress properties
LI Luke
XING Yongxiang
YAN Shidang
WANG Xiaopeng
Abstract：[Objective]The gear contact fatigue failure mechanism has become an important bottleneck problem to be solved in the industrial circles.A key method for the effective prediction of gear contact fatigue failure is the correlation mechanism between the strength gradient load capacity characteristics of the carburized gear modification layer and the mechanical response of the meshing contact stress-strain.[Methods]Based on the modified layer gradient bearing effect of carburized and quenched spur gears,a coupled mathematical model for the risk prediction of contact fatigue of gears with gradient loading was developed.By employing the explicit analytical solution of rectangular microelements and the discrete numerical efficient calculation method,the singular integral contact problem of the mathematical equations of elastic half-plane contact stress components was resolved.The objective was to investigate the characteristic parameters associated with the fatigue risk failure.[Results]This study demonstrates that the stress risk domain caused by the friction tangential load increment of the characteristic parameter is a consequence of near-surface-to-surface movement.This indicates that cracks may form on the near surface and extend to the pitting failure under conditions of good lubrication.In contrast,under the poor lubrication,the surface stresses may increase,resulting in the formation of cracks and extension to the micro-pitting.The material load parameters are enhanced through the application of surface hardness increments,thereby improving the load capacity of the gear contact.The shear resistance along the depth is enhanced by the gradient increment of the residual compressive stress,and the initiation rate of tear-type cracks caused by the shear stresses is slowed down at the subsurface.And gear contact fatigue failure is easily accelerated by normal load increments.The pitting and micro-pitting crack initiation mechanisms and failure life characteristics demonstrated in the predictive model is in perfect agreement with these in actual gear running class loading tests.
Keywords：Gear transmissionContact fatigueCarburizing and quenchingMultiaxial stressLoad capacity
Publication Date：2025-09-15
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：10( 9-18 )