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A356 is one of the widely used aluminium casting alloy that has been used in both sand and die casting processes. Large amounts of scrap metal can be generated from the runner systems and feeders. In addition, chips are generated in the machined parts. The surface area with regard to weight of chips is so high that it makes these scraps difficult to melt. Although there are several techniques evolved to remedy this problem, yet the problem lies in the quality of the recycled raw material. Since recycling of these scrap is quite important due to the advantages like energy saving and cost reduction in the final product, in this work, the recycling efficiency and casting quality were investigated. Three types of charges were prepared for casting: %100 primary ingot, %100 scrap aluminium and fifty-fifty scrap aluminium and primary ingot mixture were used. Melt quality was determined by calculating bifilm index by using reduced pressure test. Tensile test samples were produced by casting both from sand and die moulds. Relationship between bifilm index and tensile strength were determined as an indication of correlation of melt quality. It was found that untreated chips decrease the casting quality significantly. Therefore, prior to charging the chips into the furnace for melting, a series of cleaning processes has to be used in order to achieve good quality products.

In aluminium‐melting operations, a dross layer containing 85% metallic Al forms on the surface of the molten aluminium bath. Therefore, a significant amount of metal is removed from the furnace with the dross. Melt losses are one of the most important economical points in the melting operations. In the first part of the present study, a series of reverbaratory furnace drosses received from several aluminium plants located in Turkey were examined to determine their compositional and structural characteristics. Following crushing and grinding operations, drosses were dimensionally classified into 5 groups. Metallic Al, Mg, Zn, Fe and SiO2 contents of each group were analyzed separately. The metallic aluminium content of the group +4 mm is found to be approximately 75% while that of −0.5 mm group is 25%. Another fundamental finding is the high Mg content present in the drosses. Furthermore, Fe and SiO2 contents increase with decreasing particle size of the dross. In the second part of the investigation, experiments were carried out on the treatment of the salty slags to obtain salt, aluminium and non‐metallic products which can be used for various purposes. Leaching and crystallization in an evaporator is employed to determine the optimum conditions for the recovery of flux from the salty slag.

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