Dry wear behavior of rheo-casting Al-16Si-4Cu-0.5Mg alloy

流变铸造Al-16Si-4Cu-0.5Mg合金的干摩擦行为（英文）

Dry wear behavior of the rheo-casting Al-16Si-4Cu-0.5Mg alloy was investigated by micro-scratch and dry sliding weartests. Analyses of the microstructure, scratch grooves, wear tracks, worn surfaces and wear debris of the alloy were carried out byoptical microscope and scanning electron microscope. The microstructural analysis showed that via rheo-processing, the primary Siwas refined and rounded, eutectics dispersed more homogenously, and even the skeleton AlFeMnSi phase was fragmented into facetshape. Micro-scratch test showed that the microstructural refinement resulted in better wear resistance. Dry sliding wear test revealedthat the rheo-processed sample exhibit obviously superior wear resistance because of the microstructure improvement. The dominantmechanism in mild wear condition is abrasion, but it turned to adhesion and oxidation in high applied load and fast sliding velocityconditions.

采用干滑动摩擦测试和微观刮痕测试研究流变铸造Al-16Si-4Cu-0.5Mg合金的干摩擦行为。通过光学显微镜、扫描电镜对合金显微组织、微观刮痕沟槽、宏观磨痕、磨面以及磨削进行观察分析。显微组织分析显示,经过流变处理,合金初生硅得到细化并更为圆整,共晶组织分布更为均匀,骨骼状的Al Fe Mn Si相得到破碎细化。微观刮痕测试显示,合金显微组织的细化提高了耐磨性能。干滑动摩擦测试表明,相比传统铸造,流变处理后合金耐磨性能得到明显的提高。微缓摩擦条件下,磨损以磨粒磨损为主。强摩擦条件下,表面氧化和粘着磨损为合金磨损失效机制。