The Quality Improvement of Molten Aluminium Alloy in Melting Process by Stirring Process and the Degassing Technique

Abstract

The fuel-fired crucible furnace is very popular for melting of aluminium alloys. This melting technique provides good control of hydrogen gas in aluminium casting. The fuel type is LPG for convenience and low cost of production in small and medium foundry. However, the quality of the melt such as homogeneity of chemical composition is not good and stirring is normally required. In this paper, the rotary degassing system was used to improve the quality of the molten aluminium alloy. By control the homogeneity of chemical composition and reduces other impurities such as Iron (Fe). Two different inert gases, argon and nitrogen, were used to treat the melt. The combination of blade design, type of gas and rotation speed is the key success to improve the quality of molten aluminium alloy in this study. Moreover, this rotary degassing system can be used to control pouring temperature which is one of the most important parameters for the consistency of casting quality. Therefore, the rotary degassing system will be of benefit to control the homogeneity of chemical composition, control the pouring temperature, save production time and increase productivity of aluminium melting and casting.