GB546899A - Improvements in or relating to aluminium base alloys - Google Patents

Abstract

546,899. Alloys; annealing. FAIRWEATHER, H. G. C. Oct. 23, 1941, No. 8089/42. Divided out of 546,378. [Classes 72 and 82 (i)] Aluminium alloys contain 1.2-12 per cent. of zinc, 0.05-1.5 per cent. of chromium, 0.4-2 per cent. of iron, and an amount of magnesium equal to 35-45 per cent. of the zinc. There may also be present 0.15-2.5 per cent. of silicon, calcium being added if necessary in an amount such as to reduce the upper limit of silicon uncombined with calcium to 1.5 per cent., the magnesium being then increased by an amount equal to 174 per cent. of such uncombined silicon. There may also be an excess of magnesium over these amounts up to 1 per cent. The alloys may also contain any of the following: 0.1-1.5 per cent. of nickel, 0.2-1.5 per cent. of copper, and a total of 0.005-0.5 per cent. of one or more of 0.1-0.5 per cent. of zirconium, 0.01-0.5 per cent. of tungsten, 0.005-0.1 per cent. of boron, 0.01-0.5 per cent. of molybdenum, 0.01-0.5 per cent. of vanadium, 0.05-0.5 per cent. of titanium, 0.01-0.5 per cent. of niobium, and 0.05-0.5 per cent. of tantalum. The alloys may be heat-treated or age hardened ; for example castings may be quenched and aged for 3 hours at 125‹ C., or they may be aged at room temperature with or without quenching from the mould.