干摩擦条件下天然橡胶/钢的磨损机理研究

Wear Mechanisms of AISI1020 Steel against Natural Rubber under Dry Sliding

采用 FAL EX试验机考察了 2 0 #钢 /天然橡胶在干摩擦条件下的磨损机理 .用扫描电子显微镜分析了 2 0 #钢和橡胶磨损表面形貌 ,用 X射线光电子能谱仪分析了金属和橡胶磨损表面元素的含量及化学状态 ,用镜面全反射傅立叶红外光谱仪分析了橡胶磨损表面官能团的变化 .结果表明 ,2 0 #钢 /天然橡胶摩擦副发生了粘着磨损 ,其磨损机制为 :金属及金属氧化物与天然橡胶大分子自由基在摩擦表面发生反应 ;在亚表层以金属与大分子自由基的反应为主 ,主要产物为含有 Fe- C的金属 -聚合物 ;金属本身发生氧化 ,主要产物为 Fe2 O3、Fe O和 Fe3O4,而在亚表层的主要产物以 Fe O为主 .表面膜可能通过化学键。

The wear mechanism of AISI1020 steel by natural rubber under dry sliding was investigated. The worn surface morphologies and chemical compositions of the steel and rubber were observed by scanning electron microscopy and X-ray photoelectron spectroscopy respectively. The functional groups on the worn surface of the rubber were analyzed by Fourier transform infrared spectroscopy. It was found that the wear of the steel by the rubber is mainly characterized by interfacial adhesion and mechanochemical reaction between the surfaces of the steel and rubber, accompanied by the surface oxidation of the steel. The iron atoms and oxides on the steel surface react with the macroradicals of the rubber, therefore the products such as Fe-polymer compound and ferrous oxide-polymer complex are generated. At the subsurface of the steel, the activated iron atoms react with the macroradicals and produces Fe-polymer complex. The main oxides on the steel surface are Fe2O3, FeO and Fe3O4, while that at the steel subsurface is FeO. The transfer film on the steel surface helps to restrain the oxidation of the steel. By keeping off the direct contact at the rubbing surface of the steel and rubber, the abrasive wear can be restrained.