Mechanical Properties and Microstructure of Mg-SiCp Composite Sheets Fabricated by Sintering and Warm Rolling

Abstract

In this study, magnesium matrix composite sheets were fabricated by applying powder metallurgy and warm rolling methods. After preparing required mixtures of magnesium powder and SiC particles in different conditions, they were cold-pressed and sintered. Then, the sintered specimens were warm rolled through different numbers of passes. The effects of ball-milling process and the number of rolling passes were investigated on the tensile strength, hardness, microstructure, and fracture surface of magnesium matrix composites. The results were compared to those monolithic magnesium specimens (without reinforcement particle) produced in a way similar to that of the composites. The results show that among different factors (i.e., ball-milling process, the presence of SiC particles, and the number of rolling passes), the number of rolling passes is the most effective parameter on increasing the ultimate tensile strength (UTS),Vickers microhardness, and grain refinement. In this regard, UTS of the samples was increased at least 163% between second and sixth rolling passes. Moreover, for the sintered and six-pass rolled composite samples, microhardness and grain refinement were improved, respectively, about 30 and 70%.