TiCp/Ti6Al4V复合材料的耐磨性及磨损机制

为表征颗粒增强钛基复合材料在恶劣的磨粒磨损条件下的磨损行为,对熔铸法制备的TiCP/Ti6Al4V进行了磨粒磨损条件下的耐磨性试验,并利用SEM、EDX等技术分析了复合材料的磨损过程及磨损机制.研究表明:TiCP/Ti6Al4V复合材料的抗磨粒磨损性能,总体上随TiC颗粒体积分数的增加而提高,载荷越大、磨损时间越长,复合材料越容易表现出优异的耐磨性能;TiC的形态影响着耐磨性的提高,细小颗粒状或羽毛状TiC单位体积增加对耐磨性的贡献,比枝晶状TiC单位体积增加对耐磨性的贡献大约3.5倍;复合材料在磨损初始阶段,其磨损机制以形成犁削和磨沟为主,形成一次磨屑,随着增强相含量的提高,一次磨屑逐步减少,磨损以犁沟和剥层磨损为主,需要磨粒的反复作用才能形成磨屑,因此,耐磨性得到提高.

Wear resistance and wear mechanism of TiCp/Ti6Al4V composite

To characterize wear behaviors of particulate-reinforced titanium matrix composites in abominable condition, wear-resistantance test was preceded in abrasive grain wear with the TiCp/Ti6Al4V composites fabricated by melting-casting. SEM, EDX were employed to analyze the wear process and wear mechanism. The results show that wear resistantance of TiCP/Ti6Al4V composite increases with the increase of TiC particle volume fraction. The composite has better wear-resistant performance with heavier load and longer wearing time. Morphology of TiC effects the increase of wear-resistance. Wear resistance increase 2.5 times due to the unit volume increase of TiC with fine particle shape or feather shape than that with dendrite shape.Plough chop and wear ditch are formed in initial wearing period of the composite, and first wear debris is formed. First wear debris reduces gradually with the increase of reinforcement content. Wear gives priority to furrows and peeling wear. It must act on repeating by abrasive grain to form wear debris, therefore wear resistance of TiCP/Ti6Al4V composite is increased.