PENGARUH KECEPATAN PUTAR, PERLAKUAN PANAS T6 DAN PENAMBAHAN INOKULAN Al-TiB PADA CENTRIFUGAL CASTING TERHADAP SIFAT FISIS DAN MEKANIS PADUAN ALUMINIUM COR A356 VELG SEPEDA MOTOR

Centrifugal casting is one method of casting that used a centrifugal force in a spinning mold. This method is used widely to produce cylindrical components. One of automotive products which can be produced with this method is motorcycle wheel. The objective of this research is to investigated the effect of rotational speed, T6 heat treatment and the addition of Al-TiB inoculant on microstructure, the physical and mechanical properties of aluminum alloy A356 motorcycle wheel in centrifugal casting. The material used was aluminum alloy A356. The main composition of this material was 6.55% Si and 0.40% Mg. The molding temperature and pouring temperature were 250 o C and 750 o C with a variation of rotation is 300, 500, 700, 800, 900, 1000 rpm and 1000 rpm with Al-TiB inoculant. The temperature of T6 heat treatment was 535 o C for 4 hours and 155 o C precipitation aging for 3 hours referred on ASTM. The hardness, the tensile strength the toughness and the density of castings increase with molding rotational speed. The T6 heat treatment process increase the hardness, the tensile strength and the toughness to an average of 37.42%, 39.94% and 17.01% respectively. The addition of Al-TiB inoculant in cast aluminum alloys at 0.008% is not significant influence on the mechanical properties of casting. The microstructure indicates a change on shape and size of grain with rotational speed, T6 heat treatment. The addition of Al-TiB inoculant change the shape of grain