Production and characterization of AA6082-(Si₃N₄ + Gr) stir cast hybrid composites

ABSTRACT

The present research work emphasizes the development of hybrid aluminum (AA6082) matrix composites (HAMCs) reinforced with different weight percentages (wt.%) of ball-milled (silicon nitride (Si₃N₄) + graphite (Gr)) ceramic particulates by conventional stir casting process. Si₃N₄ and Gr are ball milled to obtain a definite density of combined powder. The weight percentage of ball-milled ceramic powder is varied from 0 to 12 wt.% in a stage of 3%. The microstructures as well as mechanical properties of the fabricated hybrid composites are analyzed. The scanning electron micrograph reveals the uniform distribution of ball-milled (Si₃N₄ + Gr) ceramic particulates in the aluminum matrix. The distribution of ball-milled (Si₃N₄ + Gr) ceramic particulates has also been analyzed with x-ray diffraction (XRD) technique. Both the hardness and ultimate tensile strength have enhanced with a reduction in percentage elongation with increase in weight percentage of ball-milled (Si₃N₄ + Gr) ceramic particulates in the aluminum matrix.

KEYWORDS:

• Hybrid aluminum matrix composites (HAMCS)
• scanning electron microscope (SEM)
• silicon nitride (Si₃N₄)
• stir casting
• tensile strength