Melt Quality Assessment in Casting of A6082 Alloy

In this study, it was aimed to examine the metallurgical structures of AA6082 alloys after the casting and homogenization process by means of changing degassing and flux ratios during melt treatment. During the casting of AA6082 alloys, billets were produced, porosity was determined by the reduced pressure test where density index (DI%), hydrogen level (ml/100 g Al) and bifilm index (BI) were examined. After the product was cast, two different homogenization process were carried out and grain sizes, microstructures and homogeneity were examined. In addition, SEM and EDS examinations were carried out and AlFeSi and Mg2Si precipitate formations were analyzed in terms of size, number and distribution. It was found that the melt cleanliness plays a significant role on the product quality. The melt quality was increased by optimization of the nitrogen gas flow rate with a refining flux application where the elimination of the splashing of the melt surface was found to be the critical parameter. Overall, it was found that the grain size had become finer, and the homogeneity rate was increased.