EFFECT OF CLUSTERING ON THE MECHANICAL PROPERTIES OF SiCP REINFORCED ALUMINUM METAL MATRIX COMPOSITES

This paper reports an aluminum matrix composite reinforced with SiC particle (SiCp/Al) using the ball-milling and hot-press sintering. The effects of SiCp content and ball-milling time on microstructure and mechanical properties of the composites were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD) and tensile tests. Microstructural investigation shows that the micro-sized SiC particles had been dispersed homogeneously in the aluminum matrix when the content of SiCp is up to 2.5 wt%. However, the particle agglomeration is observed in the composite when the SiCp content is above 3.5 wt%. The composite with 2.5 wt% SiCp content exhibits a highest tensile strength and hardness in which the improvement is 41.5 % and 25.86 %, respectively, over unreinforced aluminum matrix. But the elongation decreases with increasing the content of the SiCp, indicating that increasing the content of the SiCp degrade the plasticity of the composites. The fracture mechanism of the composites changes from ductile to brittle with the increase in the content of the SiCp.