PRESSURELESS COMBUSTION SYNTHESIS OF NiAl and Ni₃Al

The influences of synthetic mode and characters of initial compacts (density, particle size and diluent amount) on the combustion synthesis of NiAl and Ni₃Al have been investigated. The results have shown, that NiAl and Ni₃Al intermetallic compounds can be synthesized smoothly by self-reaction heat explosion process. However, Ni₃Al was synthesized with low conversion rate in case of the particle size over 100μm and without pure Ni₃Al products in case of a diluent amount 30wt%.The characters of initial compacts hardly influences the synthesis of NiAl. The synthetic ignition temperature T_ig remaines constant regardless of processing parameters. The synthesis temperature T_c decreases with the increase of particle size and diluent amount.