带磷酸锰转化涂层的自动变速器齿轮疲劳特性的试验研究  

An Experimental Study on the Fatigue Characteristics of Automatic Transmission Gears with Manganese Phosphate Conversion Coating

作　　者：臧立彬[1] 陈勇[1] 冉立新 贾森[1] 高茂忠 李凯 曹展 

机构地区：[1]河北工业大学机械工程学院,天津300130 [2]壳牌(上海)技术有限公司,上海201210

出　　处：《汽车工程》2017年第10期1203-1210,共8页Automotive Engineering

基　　金：河北省高等学校自然科学青年基金(QN2016197);河北省研究生创新项目(CXZZSS2017017)资助

摘　　要：为提高自动变速器合金钢齿轮的接触疲劳寿命,将表面转化涂层技术应用到齿轮的抗疲劳点蚀中。运用化学转化膜原理在齿轮表面生成数微米的软质磷酸锰转化涂层,利用SRV多功能摩擦磨损试验机对涂层的摩擦学性能进行评价,采用共焦激光显微镜和扫描电子显微镜对涂层表面微观形貌进行观察,对不同配对副的齿轮接触疲劳特性进行了单对齿轮动力循环疲劳试验和自动变速器疲劳试验,对比分析两种自动变速器油对齿轮副疲劳点蚀的影响,对磷酸锰转化涂层的抗点蚀机理进行了讨论。结果表明,具有磷酸锰转化涂层对齿轮副的啮合初期磨合性有明显改善,齿轮表面产生数微米的软质层,填平了齿轮表面大部分凹凸切削波纹,降低了齿面的局部最大啮合接触应力和金属表面摩擦因数,改善了齿轮啮合时的油膜和润滑状况。对不同表面加工方式的齿轮采用磷酸锰转化涂层和合理选用润滑油可大幅提高齿轮抗接触疲劳能力,可作为提高汽车变速器齿轮疲劳寿命的有效方法。In order to extend the contact fatigue l i fe of al loy steel gears fo r automatic transmission （ A T ）, surface conversion coating technology is appl ied to gears fo r enhancing th e ir fatigue p i t t in g resistance. The p r in c ip le of chemical conversion f i lming is employed to generate several microns of soft manganese phosphate conversion coat-ing on gear surfaces, the tr ibological performance of coatings is evaluated by SRV m u lt ifu n c t io n a l f r ic t io n and wear tester, and the surface micro-topography of coatings is observed by confocal laser scanning microscope （ C LSM ） and scanning electron microscope （ SEM ）. The power cycle fatigue test of single gear p a ir and automatic transmission fa-tigue test are conducted on different matching gear pairs to compare th e ir contact fatigue characteristics. The effects of two kinds of automatic transmission f luid （ ATF ） on the fatigue p i t t in g of gear pairs are comparatively analyzed, and the pitting resistance mechanism of manganese phosphate conversion coatings is investigated. The results show that the initial running compat ibi l ity of gear p a ir w i th manganese phosphate conversion coatings is s ig n if ica n t ly im -proved. A soft layer of several microns is generated on the surface of gear teeth that f i l ls up the most cut t in g ripples on gear surface, and hence reduces the maximum lo cal meshing contact stress and the f r ic t io n coef ficient of metal surface and improves the conditions of oi l f i lm and lu b r ic a t io n du r in g gear meshing. In one w o rd , apply ing manga-nese phosphate conversion coating to gears with dif fe re nt surface machining and using properly selected A T F can sig-nificantly enhance the contact fatigue resistance of gears and might be an effective way of extending the fatigue l i fe of automotive transmission gears.

关 键 词：磷酸锰涂层 自动变速器齿轮 接触疲劳寿命 摩擦磨损 

分 类 号：U463.2[机械工程—车辆工程]