【作者】 刘沅东；

【导师】 王成彪； 刘家浚；

【作者基本信息】 中国地质大学（北京） ， 地质工程， 2010， 博士

【摘要】 滚动轴承作为机械设备主要的传动承载件,在工作过程中会受到很大的压力和摩擦力,在滚体与滚道之间容易发生磨损,从而降低轴承的工作寿命影响到机械设备的正常运行。使用固体润滑技术可以有效提高处于边界润滑条件下接触表面的耐磨性能,延长其使用寿命,并能降低噪音和震动。FeS是一种典型的固体润滑材料,对钢铁表面进行低温离子渗硫处理可以改善表面的润滑状态,较好地提高钢铁材料抵抗磨损的性能,但是由于表面渗硫层厚度较薄,在较苛刻的工况条件下影响到其作用的发挥。为了改善GCr15轴承钢渗硫层在苛刻条件下的摩擦磨损性能,本文在润滑介质中使用了含S元素的油性极压抗磨添加剂及FeS固体微粒添加剂,希望通过使用添加剂来补充表面渗硫层的损失。在GWL-1000型摩擦磨损实验机上对比研究了在油和脂润滑的条件下GCr15钢渗硫层与不同添加剂复合使用时的摩擦磨损性能。利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、扫描俄歇探针(AES)、X射线光电子能谱(XPS)等微观分析仪器全面观察分析研究了薄膜的形貌、组织结构、元素原子价态与元素分布等。研究结果表明,通过一定的工艺手段,可在GCr15轴承钢表面制备一层厚度为1~5μm的FeS层,轴承钢在油润滑条件下摩擦磨损性能可以得到一定的提高,但渗硫层的作用在较高的转速载荷会消失;轴承钢渗硫层与含S的油性添加剂复合润滑时,只有当硫化层在较温和的磨损条件下破坏程度较小,可以在较长时间发挥作用时,硫化层与添加剂之间可以起到较好的复合效果;使用含FeS微粒的润滑油润滑时,渗硫盘和基础盘的摩擦磨损性能都得到明显的提高,渗硫盘与FeS微粒的复合效果更好;在脂润滑情况下,轴承钢渗硫层和使用含FeS微粒的润滑脂都可以有效地提高其减摩抗磨性能,当轴承钢表面渗硫层与含FeS微粒润滑脂复合使用时,只有在低速高载时才显示出较好的复合效果。本文对于复合润滑的研究表明,在一定的润滑条件下,选择合适的添加剂与轴承钢表面渗硫层进行复合使用可以较好地提高渗硫层在苛刻条件下的摩擦学性能。更多还原

【Abstract】 Rolling bearings usually work at high pressure and rotation speed for carrying load and transmitting the movement. The wear of raceway and roller of bearings is the main failure mode and factor to determine the service life of bearings. The anti-wear property of contact surfaces under boundary lubrication can be obviously improved by using solid lubrication technology. FeS is a typical solid lubricant. Iron sulfide (FeS) films can be easily prepared on the steel surface using low-temperature ion-sulfuration technique, and the sulfide layer can improve the lubrication state of steel surface and enhance their anti-wear properties. The sulfide layer on the 52100 steel surface is usually very thin, so its anti-wear effect is insufficient under harsh conditions.In order to improve the tribological properties of sulfide layer under harsh contions, the sulfur-containing extreme pressure anti-wear additives and FeS micro-partices were added in the lubricant based on the idea of using the additives to replenish the loss of sulfide layer in the wear process. The synergistic effect between additives and sulfide layer under the lubrication of oil and grease was investigated by a self-made friction and wear tester GWL-1000. SEM equipped with EDS were employed to observe the morphologies of surface, cross-section and wear scar of films, XRD was adopted to detect the surface phase structure. AES was used to detect the elements variation along depth of the sulfide layer and XPS was adopted to identify the valence state of boundary lubrication film.The experimental results showed that the FeS layer has been formed on the steel surface, its thickness is about 1~5μm. The anti-wear properties of bearing steel under oil lubrication can be improved remarkably when using low-temperature ion-sulfuration technique. But the sulfide layer would lose its solid lubrication effect under harsh conditions. The synergistic effect between sulfide layer and sulfur-containing additives will be not good when the FeS layer is destroyed under harsh condition in a short time. However, the composite lubrication can possess an ideal synergistic effect when the FeS layer can last a longer time. The wear properties of plain disk and sulfurized disk can be obviously improved when lubricated by the oil containing FeS particles. The composite lubrication effect of sulfide layer and FeS particles in oil is better than that by single lubrication. The friction and wear properties of bearing steel with sulfide layer and under grease lubrication with FeS particles show also obviously impoved results, however, the good synergistic effect for duplex use of sulfide layer and FeS particles in grease can be found only under the condition of low speed and high loading.The research of this dissertation demonstrated that the composite lubrication of suitable additive and sulfide layer can signicantly increase the tribological properties of friction-pairs under harsh conditions.更多还原