A new experimental technique to investigate the α2/γ interface of lamellar TiAl alloy three dimensionally

The abundant two-dimensional defects, lamellar interface, have an important role in the deformation behavior of lamellar TiAl alloys. Transmission electron microscopy (TEM) has been used to investigating the lamellar interface. However, a very limited area only could be observed by using TEM. The observation of interface morphology and dislocations inner α2 phase of lamellar TiAl is very difficult by using TEM. The purpose of this study is to propose a new experimental method to observe the lamellar interface perpendicularly and investigate the crystallographic morphology of the α2 lamellar interface. The γ phase of the lamellar TiAl alloy was selectively dissolved and the α2 phase was separated from the TiAl lamellar alloy without significant damage. These separated α2 plates were observed with atomic force microscopy (AFM), scanning electron microscopy and TEM for the investigation of dislocations and interface of the α2 phase in the lamellar TiAl alloy.