Effect of carbide ceramics and coke on the properties of dispersion strengthened aluminium‐silicon7‐magnesium hybrid composites

Abstract

In this study, aluminium‐silicon7‐magnesium alloy was reinforced with carbide ceramics (silicon carbide and boron carbide) and coke microparticles. The composite samples (S1, S2, and S3) with 4 %, 8 %, and 12 % by weight of silicon carbide and boron carbide microparticles and 8 % by weight of coke micro particles respectively, were prepared through the ultrasonic assisted melt‐stir casting route. It was observed from the literature that only a few research works reported the cumulative effect of adding these micro‐particulate reinforcements within aluminium‐silicon7‐magnesium alloy. The microstructural evaluation revealed uniform dispersion of particulate reinforcements. Area energy dispersive x‐ray spectroscopy scan results proved the presence of the reinforcement particles as heterogeneous phases at distinct zones. The samples undergone tensile tests failed under the brittle fracture mode. The ultimate tensile strength of the composites improved by about 27.4 %, the % elongation improved by about 6.8 %, and Vickers microhardness dropped 1.9 % to the maximum. Dimples were observed in the fracture morphology analysis and it was mainly due to the mixed ductility of the sample S2. An abrasive wear mechanism was observed in the worn‐out sample S2. The wear rate decreased significantly with an increase in weight fraction of the reinforcements.

Synergistic effects of cold rolling and age hardening on the hardness and tensile characteristics of AA6061 hybrid composites

“…The process involves melting the matrix alloy 6061 in an electric resistance furnace heated to 760 °C. To improve the wettability of the SiO 2 and Cu particulates with the matrix 3 wt% Mg is added to the molten metal [30,31]. Moreover, the SiO 2 and Cu particles were preheated to 500 and 300 °C, respectively to improve the dispersion of the reinforcement particles in the aluminium alloy matrix.…”