METHOD OF PREPARING MODIFIED SILUMINS Russian patent published in 2001 - IPC

FIELD: metallurgy. SUBSTANCE: invention relates to silumins alloyed with copper, magnesium, titanium, and zirconium. Proposed method involves use of halide salt fluxing agent containing eutectic KCl.NaCl with NaF additive and consists in the following: initial batch containing up to 40% of its own production utilizable waste or secondary silumin is charged into preheated salt melt of modifying mixture, resulting melt is aged under salt bed, separated, and cycle is repeated. According to invention, salt melt is heated to 770-790 C and into it are charged successively initial batch and aluminum-based foundry alloy with alloying additives selected from copper, silicon, titanium, and zirconium, Al-Cu alloy containing 38-40% copper, Al-Ti alloy containing 2% titanium, and Al-Zr alloy no more than 0.6% zirconium; and resulting alloy is aged at above-indicated temperature for 10-30 min, after which temperature is lowered to 710-720 C and magnesium-containing foundry alloy is added. EFFECT: considerably simplified technology, avoided oxidation of refractory alloys in melting process, and reduced waste of magnesium. 5 cl, 2 dwg, 3 tbl, 2 ex