Assessment and Control of the Damages to Cast Al Alloys During Melt Preparation and Casting

Using a high quality, clean melt is a fundamental prerequisite for production of high-quality Al castings. So far, a variety of techniques have been suggested to increase the quality of cast Al alloys including, rotary degassing and the use of fluxes and ceramic foam filters during melt preparation and casting. While the dissolved hydrogen in molten Al alloys is considered as the main cause of the formation of pores and therefore, the low quality of cast aluminum alloys, the study of the literature in this paper demonstrates that hydrogen itself has almost no negative impact on the quality of these alloys. The present paper suggests that the sole factor that impairs their quality is the presence of oxide films and inclusions. Also, this paper suggests a practical procedure to evaluate the damages to cast Al alloys during the production steps that is based on the reduced pressure test and uniaxial tensile test.