Gamma titanium aluminide rendered castable by low chromium and high niobium additives

摘要

A method for providing improved castability in a gamma titanium aluminide is taught. The method involves adding inclusions to the near stoichiometric titanium aluminide and specifically low chromium and high niobium inclusions. Niobium additions are made in concentrations between 6 and 14 atomic percent. Chromium additions are between 1 and 3 atom percent. Property improvements are also achieved.PPA preferred composition is according to the following expression:P PTi--i Al.sub.46--48 Cr.sub.1--3 Nb.sub.6--14