REACTIVE SYNTHESIS OF ALUMINIDE INTERMETALLICS

Reactive synthesis of bulk and reinforced aluminides are reviewed. When processed under optimal conditions, reactively-synthesized aluminides display room-temperature mechanical properties as good as, or better than, cast aluminides. Frequently encountered defects resulting from reactive synthesis are: (i) porosity, (ii) incomplete synthesis and (iii) loss of shape due to liquid formation. Using a simple mass balance, the amount of liquid aluminide is calculated as a function of the initial temperature of the reactants. Process maps are discussed for some of the aluminides of nickel and titanium.