Low and high temperature deformation mechanisms in TiAl alloys

Abstract

The deformation mechanisms involving ordinary dislocations are studied at various temperatures, in single-phased and lamellar TiAl alloys. In situ straining and heating experiments are performed in the transmission electron microscope (TEM) as well as postmortem studies of deformed samples. It is shown that the dislocations can move by glide or climb depending on the temperature range and that some dynamic strain aging occurs at intermediates temperatures. In lamellar alloys, the crossing of interfaces is found to play a determining role. © 2010 IOP Publishing Ltd.