In situ TEM observations of interface sliding and migration in a refined lamellar TiAl alloy

The stability of lamellar interfaces in lamellar TiAl by straining at ambient temperatures has been investigated using in situ straining techniques performed in a transmission electron microscope in order to obtain direct evidence to support the previously proposed creep mechanisms in refined lamellar TiAl based upon the interface sliding in association with the cooperative motion of interfacial dislocations. The results have revealed that both sliding and migration of lamellar interfaces can take place as a result of the cooperative motion of interfacial dislocations.