铸铁滑动摩擦副润滑状态转化之部分影响因素的考察

The Influences on the Transition of Wear Status for Cast lron Pairs in Lubricated Sliding Wear

本文利用线接触销-盘式摩擦磨损试验机对影响铸铁滑动摩擦副润滑状态转化的部分因素进行了考察,并且指出该摩擦副的润滑状态转化图可以分为部分弹流润滑Ⅰ区、边界润滑Ⅱ区(塑性流动磨损区)、边界润滑Ⅱ`区(氧化磨损区)和干摩擦Ⅲ区(严重擦伤区)。文章最后还着重就试样表面初始粗糙度对润滑状态转化的影响作了深入的分析和讨论。

On a pin-on-disk testing machine of sliding wear in linear contact, the property of friction-wear and the critical load of the transition of wear status for cast iron pairs in lubricated sliding wear have been measured. The influences of the sliding velocity, the initial roughness and microstructures on the transition of wear status have been examined. The pin specimen was made of Cr- Mo- Cu alloy iron with lamelar pearlite and graphite structure. The disk specimens were made separately by boron cast iron with lamelar pearlite and graphite and netted boronising phases, grey iron, nodular iron and vermiform iron. Some factors, which are the initial roughness of the contacting surfaces, the sliding velocity, the load, the chemistry of the lubricant, the metallurgy of the cast iron, influence the location of the various transitions for cast iron pairs in lubricated sliding wear. There is the influence of the differences of microstructure for cast on the third transition of the wear status, but not on the first transition. The transition diagrams can be divided into four regions as following: partial EHD region Ⅰ , boundary lubrication region Ⅱ (the region of plastic flow wear), boundary lubrication region Ⅱ , (the region of oxidation wear) and dry friction region Ⅲ (the region of serious scuffing). The initial roughness of the contacting surfaces influences not only on the first transition, but also on the second and the third transitions in our experiments. There is an optimum initial roughness on the contacting surfaces for the load bearing capacity of the oxidation region. There is an optimum working standard for oxide film under certain condition. The film which has the role of decreasing friction will be formed automatically on the friction surfaces under the condition. Utilizing effectively the condition, the benefit to prolong the life of friction pair should be gotten.