Wear Characteristics of a Laser Surface Alloyed Al-Mg-Si with Co Alloy Powder

The microstructure and wear resistance of a laser surface alloyed Al-Mg-Si with Co alloy powder were investigated. The experimental results indicate that a porosityfree zone can be generated but some cracks appear after laser surface alloying (LSA). In this investigation, two regions, A (surface region) and B (bottom region), are observed in the pool. Al9Co2 particles with a network structure are present in region A and block-like Al13Co4 particles are distributed in region B. The hardness of the LSA specimens is three to nine times higher than that of the Al-matrix. The high hardness of LSA specimens cause them to exhibit excellent sliding wear performance so they have a lower friction coefficient and wear rate. Notably, the critical temperature of the sliding wear resistance of the LSA specimen exceeds that of the Al-matrix by approximately 50 K.