Densification abnormality in reactive hot pressing of Ti and Al elemental powders①
(State Key Laboratory for Powder Metallurgy,
Central South University of Technology, Changsha 410083, P.R.China)
Central South University of Technology, Changsha 410083, P.R.China)
Abstract: The densification behavior of a TiAl base alloy prepared by elemental powder metallurgy has been studied. It is found that a densification abnormality occurs at 1 400℃, i.e. the compact density decreases with the increase of hot pressing temperature. By microstructural observation, including optical microscopy and TEM, it has been concluded that the densification abnormality can be attributed to the different high temperature creep mechanisms induced by microstructure coarsening in the late period of densification.
Key words: TiAl base alloy; densification; powder metallurgy; microstructure