Powder metal Al2O3 reinforced Mg5Sn matrix composites: Production and characterization

Purpose: The aim of this study is to make the production of Mg matrix composites safe and easy by PM method and to obtain composites with superior mechanical properties. Theory and Methods: A novel mixing and paraffin coating technique were applied in production process. The samples were sintered through hot pressing technique. The microstructure properties were determined by density measurements, XRD and SEM examinations. Hardness and tensile strength tests were used to determine the mechanical properties. Results: Relative density values of samples were obtained over 99%. The microstructure of composite samples consists of coaxial grains. The increase in the ratio of the reinforcement phase, that prevents grain coarsening by settling at the grain boundaries, provided a finer grained microstructure. Microstructure investigations showed that the alumina reinforcement was homogeneously distributed in the microstructure. With the increasing Al2O3 ratio, the hardness, yield and tensile strength values increased. Conclusion: The production of Mg matrix composites by the PM method has been successfully achieved. Paraffin coating technique on Mg powders prevented oxidation during production stages. Composite samples could be produced at high relative density ratios. Alumina reinforcement significantly improved the mechanical properties.