齿轮传动微点蚀与热胶合竞争性失效机制研究

Competitive Failure Mechanism of Micro-Pitting and Thermal-Scuffing in Gear Transmission

基于工程应用中微点蚀与热胶合随机发生现象,阐述了两种失效模式的损伤机理,分析了两者发生模式转变的关联规律,并提出了大扭矩宽速域传动齿轮微点蚀与热胶合竞争性失效机制的理念;在润滑油膜厚度和瞬时啮合温度计算方法的基础之上,建立了两者强度校核的统一评价准则,并基于试验测试,验证了本文中所采用技术原理的合理性与正确性,最终确定了18CrNiMo7-6与普通矿物油组合的抗微点蚀与抗胶合承载能力关联校核方法;同时,结合计算分析与试验测试,给出了热胶合发生的极限啮合温度,并通过油膜厚度和表面粗糙度的比较,推荐了微点蚀设计合理的最小安全系数.基于本文所得结论,希望能为高功率密度、宽旋转速域齿轮传动的设计提供一种分析方法.

Based on the random occurrences of micro-pitting and thermal-scuffing in the engineering application,the damage mechanisms of these two failure modes and the laws related to their transition were analyzed in this study.A concept of the competitive mechanism between micro-pitting and thermal-scuffing failure of the high-torque and widespeed-range gears was proposed.On the basis of the numerical methods of calculating the film thickness and flash temperature on the meshing faces,a combined evaluation criterion of strength check was established,and its rationality and validity was indicated by the experimental results.Finally,the bearing capacity of 18CrNiMo7-6 and plain mineral oil against scuffing and pitting damage was determined.Meanwhile,in the combination of numerical calculation and experimental tests,the ultimate contact temperature of thermal-scuffing was put out.The minimum safety factor in the design of anti-pitting was also proposed through the comparison of oil film thickness and surface roughness.Based on the conclusions,it is hoped to provide an analysis method for the designing of gears with high power density and wide rotation speed range.