Identification of microstructural mechanisms during densification of a TiAl alloy by spark plasma sintering

► Mechanisms of a TiAl alloy powder densified by spark plasma sintering are identified. ► Microstructure evolution of the powder is followed during the sintering cycle. ► As-atomized supersaturated powder comes back to equilibrium. ► Densification occurs by plastification of the particles at high temperature. ► No mechanisms related to electric current are observed.