Aluminum-15 wt. % zircon metal matrix composite was fabricated using spark plasma sintering method at the temperature of 450°C and holding time of 4 min. The bending strength of 284±21 MPa and microhardness of 171±14 Vickers were determined for produced composite. XRD investigations proved that almost no decomposition of zircon particles as reinforcement occurred. SEM studies revealed the homogenous dispersion of reinforcement particles in the aluminum matrix.

Abstract Microwave assisted rapid sintering was carried out to fabricate aluminum-ZrB2 metal matrix composites containing 1 wt% cobalt and 10, 15 and 20 wt% ZrB2 as the reinforcements at temperatures of 600, 700 and 800°C. The results showed that the highest values of density and bending strength (97% of theoretical density and 240 MPa, respectively) were obtained in a composite containing 15 wt% ZrB2 and 1 wt% Co sintered at 600°C. Furthermore, the optimum values of compressive strength and hardness (350 MPa and 63 Vickers, respectively) were measured for a composite containing 20 wt% ZrB2 sintered at 600°C. At all sintering temperatures, XRD analysis revealed ZrB2 and aluminum as the only crystalline phases. Microstructure investigations demonstrated a homogeneous distribution of ZrB2 particles in the aluminum matrix.