【摘要】 采用熔体内部喷粉联合搅拌和超声处理制备了纳米SiC_p增强0.2SiC_p/ZA-32.5复合材料,研究了不同超声功率处理后铸态复合材料的干摩擦行为和磨损性能。结果表明,超声处理不仅能有效分散纳米SiC_p,还能细化铸态组织;干摩擦时,在稳定阶段铸态试样的磨损率随超声功率的增加而减小,同时,磨损亚表面温度和磨损纵断面显微硬度随着超声功率的增加而增加,接触面硬度最低,亚接触面硬度增加,远离接触面的硬度最大,并且摩擦磨损中摩擦接触面的硬度比铸态的降低了14%。经800W超声处理试样的摩擦磨损率达到0.45μm/m,说明超声处理能显著提高纳米SiC_p增强的锌基复合材料在摩擦所产生的高温工况下的耐磨性。更多还原

【Abstract】 SiC particle reinforced 0.2% nano SiC_p/ZA-32.5 composites were prepared by powder injection of melt inside and stirring combined with ultrasonic treatment,and the dry friction behavior and wear performance of the as-cast composites with different ultrasonic powers were investigated.Meanwhile,the relationship between wear properties,worn surface morphology,wear temperature,Micro-vickers hardness of wear section status as well as microstructure were analyzed.The results reveal that ultrasonic treatment can not only disperse effectively the nano sized silicon carbide particles in the matrix alloy,but also refine the as-cast grain size.During the stabilization process of dry friction behaviors,the wear lose rate of the as-cast specimen is decreased with the increase of the ultrasonic power.At the same time,the wear temperature and hardness of wear section status are increased.Although micro vickers hardness of the contact surface and that of the sub-contact surface are increased,micro vickers hardness of the part far from the contact surface has the largest value.Micro vickers hardness of the contact surface is reduced by 14%during friction wear condition.The optimal wear rate of the casting composite is 0.45 mm/m treated by 800 Wultrasonic power,and ultrasonic treatment can improve significantly the wear resistance of zinc matrix composites reinforced by nano silicon carbide particles under high temperature conditions caused by friction.更多还原