汽车发动机链条的多次冲击磨损特性研究

Research on Wear Characteristics of Automotive Engine Chains under Multi-cycle Impact

通过发动机总成和汽车道路行驶试验,研究了汽车发动机机油泵链的磨损机制,绘出了汽车链在不同试验工况下的磨损伸长曲线,阐述了汽车链主要零件的循环软化与循环硬化特性,通过微观分析研究了汽车链主要零件的磨损表面形貌和多次冲击疲劳裂纹,通过联结牢固度的压出力试验,分析了汽车链过盈配合零件间的微动磨损现象及其产生的原因.结果表明:销轴和套筒零件表层的裂纹生成、扩展与剥落是汽车链的主要磨损机制;在高载、高速及变速工况下滚子零件产生循环硬化现象,在正常载荷和速度下滚子零件产生循环软化现象;随着载荷和速度的提高,汽车链过盈配合表面的微动磨损加剧.

Based on the experiments of engine assembly and automotive road running, wear mechanism of engine oil pump chain was studied, the wear curves of automotive chains in different test condition were drawn respectively, the circular hardening and circular softening characteristics of the main parts of automotive chains were expounded. Wear surface morphology and impact fatigue flaw of the main parts of automotive chains were studied at micro scale. By measuring the force to pull out a component from a firmly assembled component combination, fretting wear of matching parts were analyzed. The main wear mechanism of automotive chains was fatigue, flaking of the surface of pin and bush. The roller was hardened circularly at high load and high speed with variation. The roller was softened circularly at common load and speed. The fretting wear between matching parts became severe with increasing of load and speed.