Scratch hardness and mechanical property correlation for Mg/SiC and Mg/SiC/Ti metal–matrix composites

Scratch hardness results conducted on magnesium based metal–matrix composites using submicron SiC (4.8–15.4 wt%) and micron sized Ti (2.7 wt%) particulates are presented. These results are further correlated with composites' bulk mechanical properties such as the normal hardness, the elastic modulus and the yield strength. The data show that the scratch hardness correlates well with the normal hardness and the elastic modulus as all of these parameters increase with an increase in the weight percent of the reinforcing particulates. The scanning electron microscopic study reveals that the composites have greater tendency to form brittle cracks at the edges and wear debris in comparison to pure Mg. The addition of 2.7 wt% of Ti marginally increases the scratch resistance of the composites.