Improvements relating to nickel-chromium alloys

An alloy resistant to creep and to corrosion at high temperatures contains Cr 4-12 per cent, Ti 3.5-8 per cent, Al 0.9-5 per cent, the combined contents of Al and Ti being 4.5-10 per cent, and the balance, except for impurities and residual deoxidants, being Ni. The alloy may also contain Co less than 10 per cent, Zr up to 0.2 per cent, B up to 0.01 per cent, C up to 0.25 per cent, Fe up to 10 per cent, W up to 5, per cent Mo up to 5 per cent, Mn up to 1 per cent, Si up to 1.5 per cent, Nb or Ta up to 1 per cent. The alloy may be subjected to a heat treatment comprising solution heating at 1050-1250 DEG C., intermediate heating at 750-1100 DEG C. and finally precipitation hardening at 650-850 DEG C. Specification 583,162 is referred to.