| 摘要 |
PURPOSE:To produce the titled alloy in which the surface part is hard and the inner part has high ductility by compounding specific ratios of each powder of W, Ni, Fe and Mo and executing green compacting, liquid phase sintering, heating and cooling and swaging working in succession under specific conditions. CONSTITUTION:The mixed powders consisting of, by weight, 89-97% more preferably 90-95% W powder, 1.5-6% Ni powder, 0.5-4% Fe powder and 2-5% Mo powder (about 1-10mu grain size of each powder) are prepd. Said mixed powders are subjected to green compacting at 1-4ton/cm<2> and further to the liquid phase sintering for about >=30min at about >=1,450 deg.C in a hydrogen stream having 0--60 deg.C dew point or ammonia decomposition gas. The powders are then retained under heating for 2-10hr at about 700-1,400 deg.C in a vacuum, neutral or reducing atm. and quenched to about 300 deg.C with about >=40 deg.C/min cooling ratio. Said heat treated body is furthermore subjected to swaging working or forging working at 2-20% working ratio. By this method, the alloy for high temp. tool member having drastically improved service life is obtd.
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