Production of TiAl sheet with oriented lamellar microstructure by diffusional reaction of aluminum and textured titanium foils

The idea that the orientations of lamellar microstructure in the sheet of T iAl intermetallic compound can be controlled by achieving the textured alph a single phase state by the diffusional reaction of aluminum and textured t itanium foils is experimentally examined. The reaction process was analyzed by DTA, EDX and texture measurements. It was found that the oriented lamel lar microstructure can be constructed by the process consisting of four sta ges; transforming stage of the pure aluminum layer to Al3Ti for avoiding th e formation of aluminum liquid phase, enriching stage of aluminum content i n the titanium layer to prevent the alpha-beta transformation during the he ating to alpha single phase state, heating stage to obtain a single phase s tale and cooling stage to form the lamellar microstructure consisting of al pha(2) and gamma phases.