Hereditary Influence of Deformed Waste on the Efficiency of Modification of Alloy Systems Al–Si–Mg and Al–Mg

Abstract

The results of studies on the effect of the charge composition on the structure and mechanical properties of cast aluminum alloys of the Al–Si–Mg (AK9ch) and Al–Mg (AMg6l) systems are presented. It is shown that the contribution of deformed waste in the composition of the charge (electrical waste of aluminum and waste of beverage cans based on alloy 3104—for AK9ch; alloy plates AMg6—for AMg6l) contributes to the formation of dispersed micro- and macrostructure of working alloys in the solid state. The effect of modification (AlSr20 master alloy—for AK9ch; AlTi5 master alloy—for AMg6l) on the structure and mechanical properties of alloys obtained by various charge variants is investigated. Experiments on the effect of the charge composition on the modifiability of AK9ch and AMg6l alloys have shown that the structure of the deformed waste is partially inherited by working alloys through the liquid state. With similar chemical compositions, smaller micro- and macrostructure sizes and increased mechanical properties (tensile strength and elongation under tension) are characteristic of alloys obtained using an increased proportion of deformed waste in the composition of the charge. It was found that, in alloys with an increased proportion of deformed waste, exceeding a certain amount of the modifier element (0.06% Sr for the AK9h alloy; 0.04% Ti for the AMg6l alloy) causes the manifestation of the effect of overmodification. This is expressed in the enlargement of the parameters of the micro- and macrostructure, as well as a decrease in the tensile strength. The results obtained show that the optimal amount of the proportion of deformed waste in the composition of the charge will make it possible in practice to reduce the consumption of expensive modifying ligatures with a guaranteed effect of modification.