Pengaruh Variasi Temperatur Heat Treatment Aluminium Composite Rolled dengan Campuran 2% Sillicon Carbida pada Suhu 350 OC, 450 OC, 550 OC terhadap Sifat Mekanik dan Mikrostruktur

Abstract

Aluminum matrix composites have good mechanical properties compared to unreinforced aluminum alloys. The mechanical properties of aluminum matrix composites can be improved through the development of research that takes into account various aspects and variables therein This research to determine the effect of heat treatment temperature variations on aluminum composite rolled at temperatures of 350oC, 450oC, 550oC on mechanical and microstructural properties. In this research, the test specimens went through several processes, namely the casting process (squeeze casting), hot rolling, and heat treatment. The casting process is carried out using aluminum A356 and the addition of 2% Silicon Carbide. The casting result is poured into the harvesting mold and the pressure is 35Mpa. The specimens resulting from castings are then subjected to a 30% reduction in hot rolling process at 350oC. The thickness of the intended specimen was 10 mm from 13 mm from the initial specimen The machining process is carried out on specimens that have been squeezed or rolled in order to evenly heat the specimens. Then the final process is by conducting heat treatment on the test specimens at temperature variations of 350oC, 450oC, 550oC with 40% brine cooling media. The highest hardness was obtained at a heat treatment temperature of 550oC with a value of 68.71 BHN, followed by a temperature of 450oC with a value of 65.36 BHN, and 350oC with a value of 64.51 BHN. The highest tensile strength was obtained at a heat treatment temperature of 550oC of 104.39 Mpa, followed by 450oC of 104.24 Mpa and 350oC of 99.63 Mpa. The highest impact was obtained at a heat treatment temperature of 350oC of 25.59 J, 450oC of 25.59 J and 550oC of 24.90 J. The microstructure obtained in this study shows the hypo eutectic silicon dispersed among the aluminum. In the microstructure, it can be seen that the homogenization of silicon and SiC at a heat treatment temperature of 550oC is very good, as evidenced by the density of the alloy that is evenly dispersed which fills the aluminum matrix making the values of hardness and strength which are directly proportional to increase.