Production of reactive sintered nickel aluminide material

摘要

Reactive sintering process for producing a shaped body containing the nickel aluminide compound Ni.sub.3 Al, which comprises sintering a compacted shaped mass containing an intimate mixture of substances, e.g. including elemental nickel powder and elemental aluminum powder in a stoichiometric atomic ratio generally corresponding to the compound Ni. sub.3 Al, by heating the mass, e.g. in a vacuum, to an elevated sintering temperature, e.g. 500-750° C., sufficiently to initiate an exothermic reaction, and at a heating rate sufficiently for consequent progressive generation of a transient liquid below the melting point of the aluminum powder and at the corresponding eutectic temperature, and upon initiation of the exothermic reaction continuing the sintering sufficiently to form a densified shaped body containing the nickel aluminide compound Ni.sub.3 Al, and having a porosity of at most about 8%, or alternatively having an essentially fully densified structure where the heating is carried out under simultaneously applied mechanical pressure for hot isostatic compaction of the compacted shaped mass.