Formation of nanocrystallized and amorphous structures in the cavitation-eroded surface for Ti3Al–Nb alloy

Cavitation erosion of Ti3Al–Nb alloy was investigated by using rotating disc equipment. It is showed that Ti–24Al–15Nb–1Mo alloy has excellent cavitation erosion resistance. The cavitation-eroded surface was observed by TEM and nanocrystallized and amorphous structures were found in some zones. On the basis of experimental results and analyses, the impacts of microjets can cause plastic deformation in the specimen surface layer. Because of the transient high temperature produced by the collapse of bubbles, some deformed zones are recrystallized and a nanocrystallized structure is formed. The nanocrystallized structure with lower melting point is then molten by transient high temperature and quickly solidified in water, which produces an amorphous structure.