The effect of pouring temperatures to tensile strength and porosity of aluminium processed with vacuum casting

Abstract

Pouring temperature also affects the mechanical properties of aluminium. High pouring temperature will make aluminium grains become large and a lot of gas will be trapped into the liquid metal when the metal is poured into the mould. The right temperature will prevent metal porosity and the metal does not freeze before filling the entire moulds cavity. The casting process used permanent mould. Temperature of the moulds was 150 °C and the pressure 0.35 atm (absolute pressure). Pouring temperature were 750, 800 and 850 °C. The increasing pouring temperature reduce the tensile strength and specific density of aluminium. Pouring temperature aluminium in vacuum casting system at 750 °C produce the highest tensile strength (130.26 MPa). The specific density of the aluminium is 2.65 g/cm 3