GB656476A - Aluminium alloy - Google Patents

Abstract

An aluminium base alloy has the following composition:-Mg 1.5-2.5 per cent; Zn 2.8-4.8 per cent; Mn 0.25-0.7 per cent; Cr 0.1-0.5 per cent; Be 0.02-0.25 per cent or Be 0.01-0.25 per cent together with some Ag the total content of Be and Ag not exceeding 0.5 per cent. Fe up to 0.6 per cent; Si up to 0.35 per cent; Al, and impurities, the remainder. The Zn may be replaced, in part, by an equal quantity of Ni up to 1.5 per cent. Ti may be present up to 0.3 per cent and V and/or Zr up to 0.25 per cent in total. Cu may be present up to 0.2 per cent if the Ti content is greater than 0.2 per cent. Cu may be further increased up to 1.5 per cent. if the Zn content is less than 3.5 per cent, the Ni content greater than 0.3 per cent and Ti more than 0.1 per cent. The alloy may contain one or more of the elements Co, Bi, As, Li, Sb, Sn, Pb, Ce, B and Cd up to 0.1 per cent each and up to 0.2 per cent in total, one or more of Mo, Nb, Ta and W up to 0.25 per cent each and 0.4 per cent in total and one or more of Na, Ba, K, Sr, Ca, S and P up to 0.02 per cent each. Reference is also made to welding articles of the alloy with a welding rod having the same composition but in which the Mg content may be as low as 1.2 per cent.