Experimental Study of Stir Casting Using Baffles on the Hardness and Tensile Strength of AA 6061-Electroless Coated Sea Sand Composites

The stir casting process has several parameters that need to be considered such as stirring speed, wettability, stirring time, and baffle. This study aims to determine the effect of the addition and shape of the baffle on the value of hardnessHardness and tensile strength of AA 6061 composite with electroless coated sea sand reinforcementReinforcement. The process parameters of manufacturing composite are temperature of 720–740 °C and stirring speed 600 rpm for 10 min. The weight fraction of sea sand reinforced is 2%wt and the addition of wetting agent Mg is 1%wt. The highest hardnessHardness and tensile strength of the specimens were obtained by stir casting without using baffles, namely 56.38 BHN and 241.22 MPa, respectively. The composite produced by stir casting using baffles has lower tensile strength and hardnessHardness compared to the composite produced by stir casting without using baffles. The use of baffles increased the intensity of turbulence that increased porosityPorosity. The results of this study also showed that the use of round baffles in stir casting process produced higher hardnessHardness and tensile strength than flat baffles.