轿车轮毂轴承微动磨损试验分析

EXPERIMENT INVESTIGATION ON MULTIPLE FRETTING WEAR OF AUTOMOTIVE HUB BEARING

利用自行设计的轿车轮毂轴承径向式微动磨损试验系统,对三组轮毂轴承进行试验。试验轴承滚道上出现宏观条状磨损痕迹,轴承次表面约20μ m处出现了连续微孔,严重微动磨损的轴承次表面出现了近似平行于滚道的微裂纹。同时,模拟径向载荷下轮毂轴承的内部3D应力分布,结果表明,轮毂轴承载荷区出现条状应力/应变峰的幅值波动。在此基础上,结合轿车行驶时轮毂轴承的承载特点,提出了轮毂轴承广义复合微动磨损机理模型。该模型为减缓轮毂轴承微动磨损程度和提高轴承可靠性提供了新的途径。

A new test rig to measure radical fretting wear of hub bearing is introduced, by which three-group bearings are tested. It turns out that macro fretting wear gratings take place in bearing raceway, micro-apertures appear continuously about 20 μm under bearing raceway, and micro-crack parallels to bearing raceway more severe fretting wear. Followed, the 3D stress distribution of hub bearing is simulated under radical load. The simulation demonstrates spaced 3D stress stripe and its amplitude. Based on the experiment, stress distribution simulation of hub bearings under automobile's typical running conditions, a generalized multiple fretting wear mechanism model for hub bearing is proposed. The model provides a new approach for alleviating fretting wear and enhancing the reliability of hub bearings.