Surface Modification by Dispersion of Hard Particles on Magnesium Alloy with Laser

Abstract

This study aims to modify the surface of magnesium alloy, AZ91E, to resist sliding wear by means of dispersion of hard particles on its surface. TiC and SiC powders, carried by inert gas stream, were injected into a melting pool formed by laser beam. And the powder of a hypereutectic aluminum-silicon alloy was also injected. These modified surfaces were evaluated to determine their resistance to sliding wear. The main results are summarized as follows: 1) Particles of TiC and SiC are dispersed in the cladding layer of AZ91E magnesium alloy. 2) In the case of hypereutectic aluminum-silicon alloy, fine particles of Mg 2 Si intermetallic compound are dispersed uniformly. 3) These modified surfaces result much higher resistance to sliding wear than the unmodified magnesium alloy. The cladding layers of TiC or SiC show high resistance, but opposing materials are worn. The Mg 2 Si dispersed cladding layer shows high resistance, however, the wear of the opposing material is little.