HYBRID ALUMINUM MATRIX COMPOSITES REINFORCED WITH IN SITU MG2SI AND AL3NI PHASES

Abstract

Aluminum matrix cast composites (AMCCs) are engaged materials for the fabrication of accountable and especially acute pieces utilized in the high-tech scope of industry such as automotive, aerospace, electronics, etc. In the present study, hybrid aluminum base composite reinforced with in-situ produced Mg2Si and Al3Ni particles were fabricated successfully in casting moods, and the structural features of inborn reinforcing compounds was evaluated in different thermal situations of solidification. For this issue, the composite microstructure was characterized by X-ray diffraction (XRD) and optical microscope (OM). In addition, the mechanical properties were evaluated by hardness test. According to the results, increasing in the cooling rate during solidification leads to the reduction of mediate size of the Mg2Si initially crystals, enhancement of their dispensation uniformity and clear increasing of their final amount; meanwhile, the average size of Al3Ni particles decreases significantly but their content is almost the same for different conditions.