Ti-Al alloys with different Al contents were fabricated by mechanical alloying and spark plasma sintering（MA-SPS）. The effects of Al content on the composite powder morphologies

microstructure and electrical resistivity of SPS Ti-Al alloys were investigated. The results indicate that Ti-Al composite powders are flattened during high energy ball milling with Al dissolved into Ti. When the content of Al is higher than 9%

part of Al is dissolved into Ti

while the insoluble Al is broken into fine particles and attached to the surface of Ti particles

resulting in the increase of surface roughness

where the cross section of particles presents a layered structure. When the amount of Al is 6%

the microstructure of SPS specimen prepared by ball milled powders is single-phase α-Ti（Al） solid solution

which becomes α-Ti（Al） phase and fine α

2

particles precipitated in grain boundary when the amount of Al is 9%～12%. When the amount of Al exceeds 12%

the microstructure is dual-phase composed of α-Ti（Al） and α

2

-Ti

3

Al. The electrical resistivity of the alloys is firstly increased and then decreased with the increase of Al content

and slightly increased when the amount of Al reaches 18%.The electrical resistivity reaches the maximum value of 2.074 μΩ·m when the Al content is 9%.