LAUSR

Abstract High Nb-containing TiAl alloy and Ti60 alloy was brazed successfully by vacuum brazing using Ti-28Ni eutectic brazing alloy. The effect of brazing temperature on interfacial microstructure and mechanical properties of the joints was investigated. The interfacial microstructure of the joint brazed at low temperature was Ti60 substrate/Lamellar (α+β) microstructure/Ti 2 Ni phase layer + α-Ti/α-Ti layer + Ti 2 Ni/Ti 3 Al layer/B2 phase layer/TAN substrate, and the presence of Ti 2 Ni phase in the joints deteriorated the joining properties. The increasing brazing temperature accelerated the diffusion of Ni atoms into the substrates, leading to the disappearance of Ti 2 Ni and Ti 3 Al phase and the growth of B2 phase. The maximum joining strength of ∼140 MPa was obtained when brazing at 1080 °C for 10 min.