颗粒增强高铬铸铁基复合材料界面及摩擦学特性

Interface and wear characteristics of high-Cr cast iron matrix composite reinforced with cemented carbide particles

以机械破碎的废弃钨钴钛类硬质合金为增强颗粒,采用负压铸渗工艺制备颗粒增强高铬铸铁基复合材料,通过金相显微镜和X射线衍射仪分析材料的显微结构和物相组成,利用销-盘式两体磨料磨损试验机研究该复合材料的耐磨性能,并将其与工程中常用的热处理态Cr20高铬铸铁材料进行对比。结果表明:由于在铸渗过程中增强颗粒的部分熔解以及W、C、Ti、Co、Fe、Cr等元素的互扩散,在界面处形成了含Fe、W、Co等元素的多种化合物,确保界面的冶金结合;该复合材料的耐磨性比热处理态Cr20高铬铸铁材料有显著提高,且当加载载荷从0.4kg增大到2kg时,复合材料的耐磨性表现得更为突出,相对耐磨性是热处理态高铬铸铁的3.5倍以上。

The high chromium white cast iron（WCI） matrix composite reinforced with recovered WC-TiC-Co particles had been prepared by vacuum infiltration casting process. The microstructure and phase constitution of the prepared material were analyzed by using metallograph and XRD respectively, and the wear behavior of the composite was studied by pin-on-disc wear tester. The results show that the metallurgical bonding at the interface is obtained due to partial dissolution of the WC-TiC-Co particles and interdiffusion of W, C, Ti, Co, Fe, and Cr elements and formation of several compounds containing Fe, W, Co elements at the interface. The wear resistance property of the composite is much higher than that of the heat-treated high chromium WCI, moreover, when applied load increased from 0.4 kg to 2 kg, the wear resistance value of the composite is more than 3.5 times than that of the heat-treated high Chromium WCI.