Improvement in physical and mechanical properties of aluminum/zircon composites fabricated by powder metallurgy method

Metal–matrix composites (MMCs) are known as the most useful and high-tech composites in our world as well as aluminum (Al) as the best metal for producing these composites. Combining aluminum and zircon (ZrSiO4) will yield a material with the best corrosive resistance and mechanical properties like strength at high temperatures. Also, the abrasive wear behavior of these composites will be improved. In the present investigation, a study on aluminum/zircon composites has been carried out. Micro-structures of these composites in powder metallurgy conditions show different size distribution of zircon with different proportions in the composite. Also, there is a case-study about density and compressive strength and hardness of aluminum/zircon composites. The green specimens prepared by isostatic pressing of prepared powders with different zircon percentages, were sintered at two temperatures. These specimens were then investigated by different physical and mechanical testing methods to observe in which conditions the best properties would be obtained. The most improved compression strength was obtained with the specimen including 5% of zircon sintered at 650 °C.

► Yield stress and compressive strength change with increasing of zircon content. ► With increasing of zircon content of composites, the hardness of specimens increases. ► Higher temperatures cause increase in sintered density and relative density till 92%. ► Sintering temperature improves mechanical properties like yield stress and compressive strength.