Evaluation of contact fatigue risk of a carburized gear considering gradients of mechanical properties  

作　　者：Wei WANG Huaiju LIU Caichao ZHU Jinyuan TANG Chenxu JIANG 

机构地区：[1]State Key Laboratory of Mechanical Transmissions,Chongqing University,Chongqing 400030,China [2]State Key Laboratory of High Performance Complex Manufacturing,Central South University,Changsha 410083,China [3]College of Aerospace Engineering,Chongqing University,Chongqing 400044,China

出　　处：《Friction》2020年第6期1039-1050,共12页摩擦（英文版）

基　　金：the National Basic Research Program of China(973 Program)(Grant No.2018YFB2001300);the National Natural Science Foundation of China(Grant No.51975063).

摘　　要：Carburized gears are widely used in geared machines such as wind turbines.Contact fatigue problems occur in engineering practice,reducing reliabilities of machines.Contact fatigue failures are related to many factors,such as gradients of mechanical properties of the hardening layer.In this work,an elastic-plastic contact model of a carburized gear is developed based on the finite element method to evaluate contact fatigue failure risk,considering variations in hardness and strength.The Dang Van multiaxial equivalent stress is calculated via Python coding within the Abaqus framework.The gradient of yield strength along the depth from case to core is considered.The concept of local material fatigue failure risk is defined to evaluate the probability of pitting failure.The effects of design factors,such as the case hardening depth(CHD),surface hardness,and contact pressure on fatigue failure risk,are studied.As the CHD increases or the surface hardness decreases,the risk of deep spalling failure reduces.The increase in surface hardness leads to a decreased risk of pitting failure,while the variation in CHD hardly affects the pitting failure risk.

关 键 词：carburized gear multiaxial stress hardness gradient PITTING SPALLING 

分 类 号：TM315[电气工程—电机] TH132.41[机械工程—机械制造及自动化]