ALLOY DESIGN OF INTERMETALLICS

In the last fifty years, there has been a tremendous K&D effort devote d to the development of new high temperature materials. However, in se veral industries, particularly in energy, automobile, defence, chemica l and aerospace sectors, there is an intense demand for new materials. This demand has inevitably led to the study of structural intermetall ics for such applications. gamma-based titanium aluminides are a class of intermetallics which are being tested for several applications, si nce they possess good strength to weight ratio and excellent creep and oxidation resistance. Alloy design principles have been used to optim ize the properties of these alloys. These principles often have their origin in earlier research on steels and these analogies and recent ex amples of successful alloy design of intermetallics will be discussed. The basis of alloy design in gamma-based TiAl alloys is described wit h examples.