During melting process, 50 % of scrap revert is added to primary aluminium blocks (ingots) in industrial furnaces. At high pressure die-casting, scrap revert contains scrapped products and gating systems, which are containing remains of tablets, channels, overflows and elements of feeding or vacuum system. By adding scrap revert, mechanical properties of final product can be drastically deteriorated. Using elements of feeding systems, which contain oxides, final products are contaminated with inclusions and oxides. Tablet, which represents last melt of gating system, contains inclusions and is saturated with iron, which forms iron rich needles in materials microstructure and additionally deteriorate mechanical properties of final products.
Within this diploma work, we analyzed samples made from AlSi10Mg(Fe) alloy containing 50 % of primary alloy ingots and 50 % of different scrap reverts. We analyzed chemical composition on all scrap revert samples, primary alloy ingots before casting and samples after casting. We casted melted samples into steel mould, from which tensile test samples were made. With tensile tests and hardenss measurements according to Brinell, we determined how specific type of scrap revert influences mechanical properties of AlSi10Mg(Fe) alloy. Furthermore, we prepared samples for microstructure analysis, where we analyzed amount and distribution of microstructural constituents which are formed by adding different types of scrap revert. Microstructural analyses were performed using optical microscope and scanning electronic microscope equipped with EDS analysis were we analyzed different phases and inclusions which are entering the melt by adding different types of scrap revert.
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