Characterization of aluminium matrix composite of Al-ZnSiFeCuMg alloy reinforced with silica sand tailings particles
Keywords:silica-sand-tailing, grain-size, hot-compaction, sintering, hardness, wear-resistance, aluminium matrix composite
Due to the increased demand for aluminium and the prohibitive cost of producing primary aluminium, the process of making AMCs using recycled aluminium alloy as a matrix and silica sand tailing without leaching as a filler is essential to be developed. For more cost-effective, the purpose of this study is to make particulate aluminium composite matrix AMCs with a matrix of recycled aluminium and reinforced with silica sand tailing without leaching. This research involves the effect of differences in grain size and filler weight percentage on matrix Al-ZnSiFeCuMg recycled aluminium alloy powder. This study used powder metallurgy technology as well as two-way hot-compaction (300°C) and applied a sintering temperature of 550°C. Density, hardness, and wear testing, as well as microstructure analysis, were conducted to determine the characteristics of the resulting AMCs. An increase in hardness of 67% was achieved by the AMCs-164 µm-20%SiO2 specimen, which used a filler grain size of 164 µm wt.20%. Meanwhile, AMCs-31 µm-20%SiO2, which used a filler grain size of 31 µm, only increased by 63%. The wear test result also showed a lower wear rate achieved by the AMCs-164 µm-20%SiO2 specimen. The results analyses using SEM-EDS instruments showed higher agglomeration and porosity in specimens using a filler grain size of 31 µm, while AMCs using a filler grain size of 164 µm showed an even spread of filler powder. Therefore, AMCs that used 164 µm powder-sized fillers have a stronger bond between the filler and the matrix and produce AMCs that are harder than AMCs that use 31 µm fillers.