Pengaruh Variasi Serbuk Arang Tempurung Kelapa Pada Cetakan Pasir Terhadap Kekerasan Dan Struktur Mikro Hasil Coran Aluminium 6061

Abstract

This research aims to examine the effect of varying coconut shell charcoal powder content in sand molds on the mechanical properties of aluminum 6061 castings, particularly hardness and microstructure. The casting process used was sand casting with three charcoal powder compositions: 6%, 8%, and 10%. The tests conducted included Brinell hardness testing, impact testing, and microstructure observation using a digital microscope. The results showed that increasing the charcoal powder content influenced the cooling rate of the molten metal, which in turn affected both the hardness and microstructural characteristics. A higher charcoal content led to a decrease in hardness values across specimens. The 6% composition produced the most compact microstructure and the highest hardness compared to the other variations. The use of coconut shell charcoal powder presents an environmentally friendly and cost-effective alternative to improve sand mold quality in metal casting processes.