Comparative study of degassing method by using NaF-NaNO₃-based tablet degasser, technical argon gas, and pure argon gas in aluminum casting

Casting is one of the methods commonly used to produce an aluminum product. Aluminum casting product's mechanical properties are a crucial parameter that indicates the quality of the casting product. In reality, the properties of aluminum casting product can be reduced by porosity defects that appear because of aluminum's high reactivity with hydrogen gas. Therefore, hydrogen gas that formed on melt aluminum should be removed by doing the degassing method. In this research, the result of the degassing process by using different materials was compared, it is by using NaF-NaNO3- based tablet degasser and argon gas, pure and technical. The melting temperature used in this research was 750 °C, and the aluminum was poured at 670 °C. The result shows that NaF-NaNO3-based tablet degasser and pure argon gas has the best ability to reduce the number of hydrogen gas formed in aluminum casting product. The aluminum casting product's mechanical properties were enhanced, for the ultimate tensile strength the highest elevation occurs from 62.17?MPa to 214.26?MPa, for the hardness strength the highest elevation occurs from 15 BHN to 79.67?MPa, and for the impact strength the highest elevation occurs from 0.202?J/mm2 to 0.408?J/mm2.