A test procedure for characterizing the toughening of brittle intermetallics by ductile reinforcements

Abstract

A cylindrical test specimen for evaluating the toughening of brittle intermetallics by ductile reinforcements has been evaluated. A processing procedure capable of producing specimens has been devised, using HIPing, and a method for the tensile testing of the specimen has been established. Results are presented for γ-TiAl reinforced with Nb and a Ti-33 at.% Nb alloy. The toughening imparted by these materials is interpreted in terms of their strength, ductility and interface reactions, as well as loss of constraint mediated by the extent of debonding along the reaction product layers. Finally, the results are compared with those previously obtained on actual composites.