A process for the preparation of a high-strength aluminum bronze alloy

摘要

An aluminium-bronze alloy containing 9 to 11.8% by weight of aluminium and 0 to 5% of at least one additional element which forms an intermetallic compound with aluminium and which has a solid solubility in copper of less than 4%, the total amount of such additional elements not exceeding 10%, has a metallographic structure containing 5 to 95% of beta phase, the remainder being alpha phase, and has a uniformly fine grain structure with grain size less than 0.065mm. The preferred additional elements, with their permissible ranges, are as follows: .iron.2-5% .chromium.0.4-2% .titanium.0.4-2% .molybdenum.0.4-2% .niobium.0.4-2% .vanadium.0.4-2% .zirconium.0.05-0.2% while other elements which may be incidentally present include tin, zinc, lead, nickel, silicon, silver, phosphorus, magnesium, antimony, bismuth and arsenic. The alloy is fabricated by hot working at 1000-1850 DEG F., and should, either during working or subsequently, be held in the range 1050-1100 DEG F. for at least two minutes to ensure the presence of the maximum amount of alpha phase. It is then cold worked at less than 500 DEG F. Annealing at 1000 DEG -1400 DEG F. may follow, while the cold rolling and annealing steps may be repeated several times. The alloy may then be heat treated in the range 1100 DEG -1800 DEG F., and cooled rapidly to below 1000 DEG F., after which it may be treated at 500 DEG -900 DEG F. for at least 30 minutes. Use of the alloy for electric contacts, springs, diaphragms, bellows, condensers, valves, I.C. engine parts, dies, cutlery, bearings and wire is mentioned.