Thermal stability of TiAl-based intermetallic alloys subjected to high pressure torsion

This paper deals with a study of the structure and thermal stability of intermetallic TiAl-based alloys subjected to high-pressure torsion (HPT). The structural features of the HPT-processed samples have been studied by transmission electron microscopy and X-ray diffraction. In order to study the thermal stability of ultrafine-grained (UFG) structure, the dependence of microhardness on the annealing temperature in a temperature range of 150-1000 °С has been investigated. The effect of heat treatment on the grain structure stability and microhardness of the HPT-processed samples is discussed.