石墨涂层对高强化汽油机活塞裙部磨损特性的影响

Effect of Graphite Coating on the Wear Characteristics of Piston Skirt for High-Strength Gasoline Engine

为了提高活塞在发动机缸孔中运行时的润滑及抗磨损性能,在活塞裙部制备了石墨涂层,使用扫描电子显微镜(SEM)、能谱仪(EDS)等检测设备对活塞石墨涂层厚度、微观形貌及成分进行了分析,并对无涂层和有石墨涂层2种活塞样件进行了发动机台架试验,对比分析了试验前后裙部的磨损情况。结果表明:无涂层活塞样件在发动机试验后裙部主、次推力侧磨损严重,裙部外圆刀纹轮廓最大磨损量达到0.011 mm,而有石墨涂层活塞样件试验后裙部刀纹最大磨损量仅为0.004 mm,刀纹轮廓基本保持原貌,且裙部仍然有完整的石墨涂层覆盖。

In order to improve the lubrication and anti-wear properties of the piston in the operation of the cylinder bore of the engine,a graphite coating was prepared on the skirt of the piston.By various detection means such as scanning electron microscope(SEM)and energy dispersive spectrometer(EDS),the thickness,micro-morphology and composition of piston graphite coatings were investigated.In addition,the engine bench test was carried out on two kinds of piston samples with and without graphite coating,and the wear of the skirt before and after the test was compared and analyzed.Results showed that serious wear damages occurred on the the main and secondary thrust side of the non-coated piston sample,and the maximum wear amount of the circular profile of the skirt reached 0.011 mm.On the contrary,the maximum wear amount of the circular profile of the skirt was only 0.004 mm after the test of piston with graphite coating,and the profile of the skirt was kept basically as the original state,of which the skirt was still covered with a complete graphite coating.