Patent ID: 6571857
Filing Date: 2003-06-03
Classification: C22C

Abstract:
A process for producing an ingot of a beta-phase NiAl-based material, the process comprising the steps of:melting a nickel-aluminum composition having an aluminum content below that required for stoichiometric beta-phase NiAl intermetallic so as to form a melt comprising nickel and Ni3Al; adding aluminum to the melt to cause an exothermic reaction between nickel and aluminum as the melt equilibrium shifts from Ni3Al to NiAl, but at a rate sufficiently low to avoid a violent exothermic reaction, sufficient aluminum being added to the melt to yield a beta-phase NiAl-based material; solidifying the beta-phase NiAl-based material to form an ingot; and then heating and pressing the ingot to close porosity and homogenize the microstructure of the ingot.