An Investigation of Mechanical and Wear Performance of TiB2/GNPs-Reinforced ZK60 Mg Matrix Composites Fabricated Via Powder Metallurgy

In this study, ZK60 alloy, ZK60/15 wt.% TiB2, and ZK60/15 wt.% TiB2 - 0.5 GNPs composites were prepared by hot pressing. The density, microstructure, hardness, and tribological and compression behavior of the samples were investigated. Microstructure investigations showed that TiB2 particles were generally homogeneously dispersed, but GNPs particles were agglomerated. Under 10 and 40 N loads, the best wear performance was obtained with 15 wt.% TiB2 - 0.5 GNPs and ZK60/15 wt.% TiB2 samples, respectively. Abrasion at low and delamination at high loads were observed as the dominant wear mechanism. According to the mechanical test results, the highest hardness (87.1 HV), compressive yield strength (290.1 MPa) and ultimate compressive strength (379.2 MPa) were obtained for the ZK60/15 wt.% TiB2 composite. Fracture surface investigations showed that the mechanism was cleavage fracture and the presence of crack formations on the surface.