Effect of Pattern Coating Thickness on Surface Roughness and Porosity of Nodular Cast Iron (FCD) 450 Using Lost Foam Casting Method

Abstract

Lost foam casting is one of casting method that usesexpanded polystyrene (EPS) foam as a mold pattern andembedded into silica sand. When the molten metal is poured intoa mold, EPS will melt and evaporate, so the cavity is filled by themolten metal. The main objective of this research was toinvestigate the effect of pattern coating thickness on surfaceroughness and porosity of nodular cast iron FCD 450 by using thelost foam casting method. The mold pattern of EPS foam has 17kg/m3 of density and 3-24 mm of section thickness. Coatingmaterial was used a refractory material of Zircon (ZrO2) andbinder of Colloidal Silica (O2Si). In order to study effects of coatingthickness, experiments were conducted with of 0-1300 μm. FCD450 metal alloy was melted in a crucible furnace and the moltenmetal was poured into a mold at temperatures of 1350 °C-1450 °C.The experimental results showed the surface roughness decreaseswith increasing coating thickness of the EPS pattern. Uncoated ofEPS pattern influenced the casting quality. The porosity increaseswith coating thickness of EPS pattern