MANUFACTURE OF IRON-TIN-COPPER SINTERED ALLOY BY USE OF IRON-COPPER ALLOY POWDER

PURPOSE:To manufacture an iron-tin-copper sintered alloy providing satisfactory strength by low-temp. sintering, by heat-treating an iron-copper rapidly solidified powder containing copper to supersaturation in a reducing atmosphere, by mixing powdered tin with the above, and by subjecting the resulting powder mixture to compacting and then to sintering. CONSTITUTION:The iron-copper rapidly solidified powder containing 2-20wt% copper prepared by a water atomizing process is heat-treated in a reducing atmosphere at 1,000-1,100 deg.C for 5-20min. Then tin powder of -350 mesh is mixed with the above alloy powder by 0.3-4% to undergo compacting. The resulting green compact is sintered at 700-900 deg.C in a reducing atmosphere. According to this method, sintering can be carried out at a temp. lower by about 400-200 deg.C than the sintering temp. at the time of manufacturing conventional ferrous alloys, so that a sintered alloy having superior strength as compared with those manufactured by a mixing method can be obtained.