采用无压浸渗法制备了不同SiC颗粒体积分数以及不同SiC颗粒粒度的Al基复合材料。以硬质合金(80%WC+20%Co)为对摩试样进行了干摩擦试验,研究了颗粒体积分数(15%,25%,35%,45%,55%)、颗粒粒度(110μm,63μm,45μm)以及载荷(196N,392N)对SiCp/Al复合材料干摩擦磨损性能的影响。采用SEM和EDS分析了铝合金基体、复合材料的磨损表面及磨损机理。研究结果表明,颗粒体积分数在15%~35%之间时,复合材料的耐磨性明显优于铝合金基体。载荷为196N时,铝合金的磨损率是15%,25%,35%SiCp(110μm)/Al复合材料的2.16,2.76,2.07倍。SiCp/Al复合材料的磨损率随着颗粒粒度的增加、载荷的减小而降低。SiC颗粒的体积分数对铝基复合材料的磨损率和磨损机制有显著影响:SiC颗粒体积分数存在一个最佳值(25%),此时复合材料的磨损率最小,耐磨性能最好。当体积分数小于25%时,复合材料磨损率随着体积分数的增加而下降,磨损机制以磨粒磨损为主,而当体积分数大于25%时,复合材料磨损率随着体积分数的增加而上升,磨损机制以表层剥落磨损为主,同时伴有磨粒磨损。

The Aluminum matrix composites reinforced with SiC particulates of different sizes and volume fraction were fabricated by pressureless infiltration process.The effect of the size(110μm,63μm,45μm) and volume fraction(15%,25%,35%,45%,55%)of SiC particulate on the friction and wear behaviour of the composites sliding against cemented carbide(80%WC+20%Co)was investigated under dry condition.The wear tests were carried out using a block-on-ring tester at two loads of 196N and 392N under a constant sliding speed of 200rad/min.Worn surface and wear debris were examined by scanning electron microscope(SEM) and energy dispersive spectrometer(EDS).The wear mechanisms were determined.It was showed that the wear resistance of the composites was superior to that of aluminum matrix alloy when the SiC particulate volume fraction was in the range of 15%~35%.The results of the investigation also indicated that the wear rate of the composites decreased with increasing the particulate size and decreasing load.The optimal volume fraction of SiC particulate is at 25%.When the SiC particulate volume fraction was less than 25%,the wear rate of the composites significantly decreased with increasing SiC volume fraction,the wear mechanism of the composites in this period is abrasive wear.When the SiC particulate volume fraction was more than 25%,wear rate of the composites increased with increasing the SiC particulate volume fraction,the composite is characterized by delamination wear and abrasive wear.