石墨的添加对NiCr-W-Ti自润滑复合材料高温摩擦学性能的影响

发布时间：2018-05-10 21:56

  本文选题：NiCr合金 + 摩擦层　； 参考：《材料科学与工程学报》2017年03期

【摘要】：本文以Ni20Cr合金为基体添加稀有金属Ti、W粉末及石墨后,充分混合,采用机械合金化及热压烧结工艺制备了NiCr金属基复合材料,研究了石墨含量对NiCr金属基复合材料的组织结构和摩擦学性能的影响。在UMT-3高温摩擦试验机上进行了该复合材料同Al_2O_3陶瓷球的滑动摩擦磨损实验,利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)对复合材料及其摩擦测试后的形貌与结构进行观察分析,结果表明:当所添加石墨的质量分数为3wt.%时,复合材料具有相对较好的力学性能和摩擦学性能;当测试温度低于300℃时,摩擦表面未形成有效的摩擦膜,故磨损率较高;当温度高于500℃时,摩擦层中含有摩擦氧化物,摩擦表面被光滑氧化物所组成的润滑膜覆盖,对磨面具有很好的保护作用,因而磨损率降低。
[Abstract]:In this paper, NiCr metal matrix composites were prepared by mechanical alloying and hot pressing sintering by adding rare metal TiW powder and graphite into Ni20Cr alloy. The effect of graphite content on the microstructure and tribological properties of NiCr metal matrix composites was studied. The sliding friction and wear experiments of the composite with Al_2O_3 ceramic ball were carried out on UMT-3 high temperature friction tester. The morphology and structure of the composite and its tribological test were observed and analyzed by scanning electron microscope (SEM) and X-ray diffractometer (XRD). The results show that the composites have relatively good mechanical and tribological properties when the mass fraction of graphite is 3 wt.%, and when the test temperature is below 300 鈩，

本文编号：1871051