Contribution of the silicon carbide particles to the formation of the structure of magnesium cast composites

The work presents results of investigations and microstructural analyses fo r Mg-SiCp cast composites. The metallographic examination shows that the di stribution of SOC particles is uniform. Quantitative image analysis of the microstructure shows the magnesium grain size to be smaller and more unifor m than in the base metal. The studies at the level of the interfaces sugges t that the bonding between the matrix and the reinforcement is of the adhes ive type. X-ray examinations and TEM studies revealed the presence of Mg2Si compound existing as an eutectic component in the composites under investi gation. Additionally, some compounds may occur at the SiC/matrix interface as a result of chemical reactions between the constituants. The performed a nalyses have allowed to propose a model describing the process of forming t he Mg-SiC composite structure. The performed studies on the mechanical prop erties of composites have shown an increase in Young's modulus and proof st ress (R-0(2),) of composites with increasing weight fraction of SiC particl es, and a decrease in impact strength.