摘要 |
The present invention comprises the nitrogen alloying of stainless steel with a gaseous nitrogen compound such as nitrogen gas (N2), or ammonia (NH3) at high temperature wherein the reaction pressure is lowered. A base powder with properties similar to those of a martensitic stainless steel is prepared from a molten metal with the subsequent incorporation of selective additives such as cobalt, chromium, boron, copper, vanadium, niobium and mixtures thereof to improve high temperature resistance to scuffing and adhesive wear. The molten mixture is then atomized by water- or air-atomization to yield a base powder which is mixed with nitrogen or ammonia gas at various pressures in a static or fluidized bed to provide a nitrogen alloyed particulate, i.e., a nitrided particulate alloy. The powder is heated in a hot isostatic press under vacuum with argon gas at reduced pressure and later cooled to ambient temperature.
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