GB866082A - Improvements in process for producing improved alloys - Google Patents

Abstract

Oxidation hardened alloys consisting of a solid solution of a solvent metal such as Ag, Cu, Ni or Pd and 0.1% to 5% by weight of a solute metal such as Mg, Be, or Al which has a higher heat of oxide formation than the solvent metal oxide, are formed by heating the powdered alloy in an oxidizing atmosphere to preferentially oxidize the solute metal and then cold pressing and sintering or hot pressing the powder followed by plastic deformation, such as rolling, of at least 50% reduction in area. The alloy is powdered either by grinding the solid alloy or atomizing the molten alloy. An alloy of 99.7% Ag and 0.3% Mg was atomized to particles of 40m size and oxidized by heating in air to 1200 DEG F-1500 DEG F. The powder was hot pressed at 12,000 p.s.i. at 1400 DEG F. and then cold rolled and annealed or hot extruded. Cu base alloys containing 0.3% Be or 0.35% Al are oxidized in air at 1300 DEG F.-1800 DEG F. and a diffusing heat treatment is effected at the same temperature in the absence of air to allow diffusion of the oxygen. Ni base alloys with 2%-5% Al are oxidized at 1600 DEG F.-2200 DEG F.