Microstructure and property relationship between Al-4.5Cu alloy and Al-4.5Cu-Al2O3 composite developed by mechanical alloying

Abstract The present work aims to fabricate an alloy (Al-4.5Cu) and a composite (Al-4.5Cu-Al2O3) with the help of the mechanical alloying method. As compared to the high-temperature melting and casting process, mechanical alloying is a solid-state synthesis process, which requires low temperature for the synthesis of alloy and composite through powder metallurgy route. A high energy planetary ball mill mechanically alloy the Al, Cu, and Al2O3 powders for 10 h with 200 revolutions per minute to milled the alloy and composite powder mixture. Then the milled powder mixtures are compacted in a single punch die compaction machine and then sintered at 550 and 660 °C for 1hr. XRD analysis of the sintered alloy and composite predicts the formation of a new phase, i.e., CuAl2. A comparative study of density, hardness, and compressive strength values of the alloy with the composite depicts that the un-sintered and sintered composite have better properties (density, hardness, and compressive strength) due to the presence of Al2O3 and CuAl2. With increasing the sintering temperature from 550 to 660 °C, the properties further enhanced for both the alloy and composite.