Manufacturing and applications of metal powders and alloys

摘要

The present invention is directed to a method of manufacture of metal or alloy powders that uses liquid phase reduction of a metal halide, or a mixture of metal halides, to produce a metal particle coated in salts produced as a reaction byproduct. The reaction conditions can be chosen to select a range of metal particle sizes, and the salt coating prevents oxidation (or reaction with other atmospheric gases) and permits a range of applications hitherto difficult to achieve using metal powders.

主权项

1. A process for the production of powder metallurgical components comprising the steps of:
(a) reducing a mixture of at least one metal halide by molten metal reduction of the liquid phase of the metal halide in a reductant selected from an alkali or alkaline earth metal, wherein the molten reductant is present as a stoichiometric excess to the metal halide, thereby forming reaction products in a salt coating comprising molten metal, metal halide, and free metallic reductant; (b) separating the reaction products formed in step (a); and (c) forming a metal powder from a reaction product in step (b); wherein the at least one metal halide mixture comprises a mixture of metal chlorides and the reductant is metallic sodium; wherein the process is conducted as a one-pass operation in which the molten sodium metal is reacted with a liquid metal halide and the solids are recovered with only the molten sodium metal being intentionally recirculated; and wherein one or more powder metallurgical components are formed from the metal powder using powder metallurgical processing techniques.