Sintering of aluminum-zircon metal matrix composites using microwave heating

In this study aluminum-zircon composites were prepared using microwave heating. Composites were shaped with 250 MPa pressure to form 3-point bending strength samples and finally sintered in microwave furnace at temperatures of 650, 750, 850 and 950 ˚C in a graphite bed for 1 minute. Density and bending strength of samples were measured. The maximum value of fracture strength (266 Mpa) was obtained by sintering at a temperature of 750˚C. Also, X-ray diffraction as well as scanning electron microscopic pictures of the prepared composites were evaluated that zircon particles were decomposed at a temperature of 650˚ C in a microwave furnace and as a result, a solid solution of (Al,Si,Zr) was formed during sintering. Composite microstructures also showed a homogeneous distribution of reinforced zircon particles in aluminum matrix.