GB616413A - An improved aluminium base alloy - Google Patents

Abstract

An aluminium base alloy has the following composition: Si 6.00-17.90 per cent; Mn with or without Co and/or Ni 1.30-4.75 per cent; Mg 0.25-5.00 per cent; Fe 0.01 -1.50 per cent; Al the remainder, but so that the Mn content will always exceed 5.25 per cent. The Mn content will always exceed 0.60 per cent and the Ni content will always be less than 0.50 per cent unless Co is present in percentages greater than 0.05. The alloy may contain one or more of the following elements, namely, up to 2.50 per cent of Cu, up to 0.99 per cent of each and not more than 1.50 per cent in total of one or more of Ti, Sb, As, Sn, Cr, Cd, Bi, Ca, Ce, Nb, Li, La, Pb, Mo, Ga, Ag, Ta, Te, Tl, Th, W, V, Yt, Zn, Zr, B, the Ca content always being less than 0.50 per cent when Si does not exceed 7.0 per cent, one or more of Na, K, Ba, P not exceeding 0.30 per cent in total. The alloy may be in the form of a sand casting, die casting or worked part which may or may not be given an ageing treatment at temperatures up to 250 DEG C. for 15 minutes to 48 hours or a stabilizing treatment at temperatures up to 350 DEG C. for 15 minutes to 30 hours. Alternatively, it may be solution heat treated at a temperature up to 560 DEG C. for 30 minutes to 24 hours, quenched, and, if required, aged at temperatures up to 200 DEG C. for 5 to 24 hours.