润滑油黏度对高速球轴承性能及损伤的影响

为探究高速工况下润滑油黏度对轴承润滑状态及性能的影响,试验研究了Si_3N_4陶瓷和GCr15轴承钢材质的7014C型角接触球轴承在不同润滑油黏度条件下的温升和振动特性.结果表明,轴承温升及振动随润滑油黏度的增大呈现出先下降后上升的趋势,影响程度随转速的增大而增大.同时,陶瓷轴承较钢制轴承在不同润滑油黏度条件下均表现出更优越的性能.将试验结果与轴承润滑状态分析结合,讨论了润滑油黏度、润滑状态、轴承性能三者的关系,为高速角接触球轴承适用润滑油黏度的选择提供了重要依据.此外,本文还对不同润滑条件下的轴承滚动面损伤进行了分析.结果显示,全膜弹流润滑条件下,陶瓷轴承与钢制轴承滚动面损伤较小且差异不明显.部分膜弹流润滑条件下的轴承滚动面损伤严重,表面出现大量凸峰和凹谷,轴承滚动体及外滚道表面损伤较内滚道严重,钢制滚动体的表面划痕较陶瓷滚动体密且深.

Effect of lubricant viscosity on the performance and damage of high speed ball bearing

To explore the influence of lubricant viscosity on the lubrication condition and performance of bearings under high speed condition, the temperature rise and vibration characteristics of 7014C angular contact ball bearings made of Si₃N₄ ceramic and GCr15 steel under different lubricant viscosities were studied. The results show that the temperature rise and vibration of bearings decrease firstly and then increase with the increasing of lubricant viscosity, and the effect increases with the increasing of rotating speed. At the same time, ceramic bearings show better performance than steel bearings under different lubricant viscosities. By combining the test results with the analysis of lubrication condition, the relationship among lubricant viscosity, lubrication condition and performance of bearing is discussed, which provides important basis for selection of the applicable lubricant viscosity of high speed angular contact ball bearings. In addition, the rolling surface damage under different lubrication conditions was analyzed. The results show that the rolling surface damage of both ceramic bearing and steel bearing is small and with little difference under full oil-film EHL. Under partial oil-film EHL, the surface damage of bearing is serious, with a large number of micro peaks and pits. The surface damage on bearing balls and outer raceway is more serious than that of inner raceway, and the surface scratch on steel balls is denser and deeper than that of ceramic balls.