The importance of textures for determining the mechanical behaviour of intermetallics

In conventional metallurgy it is well accepted that preferred crystal orien tations in a polycrystalline material can have significant effects in modif ying properties, with notable examples found in gamma-gamma' superalloy com ponents and Fe(Si) transformer sheets. The same effects clearly should be o btained in intermetallics, but this aspect has hardly been considered until recently. The influence of textures will be examined in iron aluminide and in gamma titanium aluminides. The first compound is highly elastically ani sotropic and plastically relatively isotropic. The second compound is elast ically more isotropic and shows severe plastic anisotropy, both as single p hase gamma TiAl and in the more common two-phase (gamma + alpha (2)) form. Control of texture and of its uniformity throughout a component can have a major effect on its response to mechanical stresses. (C) 2000 Elsevier Scie nce Ltd. All rights reserved.