GB616614A - A nickel base alloy - Google Patents

Abstract

A nickel base alloy has the following composition: Si 2.00-7.50 per cent; Al 2.00-7.50 per cent; C 0.03-1.50 per cent; Co 0-9.00 per cent; Zr 0-2.00 per cent; Ti 0-1.49 per cent; Nb 0-2.00 per cent; Mg 0-2.00 per cent; Fe 0-3.00 per cent; Ni, the remainder, being always greater than 80.00 per cent, but so that the sum of the Si and Al contents together with twice the square root of the content of Ti (if present) always exceeds 8.40 per cent of the Ni present in the alloy and the total of the elements Co, Zr, Ti, Nb, Mg and Fe, if any of these elements are present, is always between 0.02 per cent and 10.00 per cent. The alloy may contain one or more of Mn, B, Be, Ba, Ca, V, Sn, Li, not exceeding 5.50 per cent in total, one or more of Cr, Mo, W, Cu, Ta, Ag, Te, Zn, Sb, Cd, Ce not exceeding 5.00 per cent in total, one or more of Bi, Pb, As, P, Tl, La, Ga, Th and Yt not exceeding 0.75 per cent in total, provided that the Ni content is always above 80.00 per cent. The alloy may be age hardened at a temperature not exceeding 700 DEG C. for up to 30 hours. If alkaline earth metals are absent, the alloy may be solution treated at a temperature above 1000 DEG C. for not more than 20 hours, which treatment may or may not be followed by ageing at a temperature not exceeding 750 DEG C. for not more than 30 hours.