EFFECT OF HYDROGEN GAS CONTENT ON SHRINKAGE DEFECTS IN ALUMINIUM ALLOY CASTINGS.

Abstract

Cylindrical castings tapered at both ends were made without feeders in a series of Al-Cu and Al-Si alloys with varying hydrogen contents. Depending on composition, a certain volume of hydrogen gas was needed to counteract shrinkage defects and form uniformly distributed gas holes in the casting. The amount of gas needed showed a correlation with liquidus temperature.