Microstructure and mechanical properties of micro-SiCp particles reinforced magnesium matrix composites with semi-solid stir casting method

Abstract

Metal matrix composites (MMCs) reinforced with ceramics offer high mechanical and good physical properties as compared with corresponding monolithic alloy. MMCs reinforced with SiCp particles in the semi-solid stir casting method was the most simple way. The purpose of the study was to investigate the difference of the microstructure and mechanical properties of SiCp particles reinforced magnesium matrix composites, as well as the changing effects on the extra level of SiCp and TiB, as well as the changing effects on the extra level of SiCp and TiB. The composites used were AZ81A Mg alloy as the matrix and SiCp as the reinforcement (3, 6, 9 wt%). The casting method used in the study was the semi-solid stir casting. The mechanical properties of the composites fabricated by different parameters indicated that semi-solid method resulted improved in nonhomogeneous particle distribution 3–9 wt.% SiCp/AZ81A composites were fabricated by the novel processing. The particle distribution was uniform in these composites. Grain sizes of composites will be much smoother by giving TiB. The ultimate tensile strength, yield strength, and elastic modulus were enhanced as the particle contents increased. The morphology of the composite between the reinforcing SiCp particle and the AZ81A matrix was to be able to unite and to be dispersed evenly. Specimens were tested focusing on the tensile strength, yield strength microstructure and SEM.