Study On Preparation And Properties Of Magnesium Matrix Composites Reinforced With Silicon Carbon Particles

In this paper, the magnesium matrix composites reinforced with silicon carbon particles under flux protection have been prepared, and metal magnesium with matrix, the size range silicon carbon particles is 5~10μm. The effects of various preparation conditions on composites microstructure and properties have been studied. The optimum preparation conditions is compound temperature 845℃, holding time 60min, holding temperature 400℃, cooling mode air cooling, The SiC particles were uniformly added to the circle magnesium cell ribbon, pretreatment methods of SiC particles high temperature roast 2h at 800℃.The phase constituents analysis of composite show that there was a reaction in the interface, producing Mg2Si structural materials with high strength hominess.The results from the properties of magnesium matrix composites reinforced with silicon carbon particles show that the hardness and density of composites increase with the increase of SiC particles addition amount. The SiC particles as the reinforceing agent helps to improve tensile strength and yield strength of magnesium matrix. When the addition amount of SiC particles is same, and other prepared conditions of composites is different, tensile strength and yield strength of composites are different. The conductivity of composites tend to gradually decrease with the increase of SiC particles addition amount.The fracture micro-appearance analysis of SiCp/Mg composites showed that fracture of composites belonged to three models of matrix tough break, interfacial de-cohesion and particle reinforcement fracture. First, the cavity was formed on SiC particles, the mode of formation are particles stripping and particles fracture. A few of the cavities grow up after formed, and then between the matrix of the particles, the small cavities were quickly formed, grow up ,thicked and fractured finally because local deformed.