Troisiéme Conférence Européenne sur les Matériaux et les Procédés Avancés
J. Phys. IV France 03 (1993) C7-485-C7-488
High temperature phase transformation kinetics and their effects on diffusion bonding of Ti-48Al-2Mn-2NbS.P. GODFREY1, P.L. THREADGILL2 and M. STRANGWOOD1
1 IRC in Materials for High Performance Applications, School of Metallurgy and Materials, The University of Birmingham, Elms Road, Edgbaston, Birmingham B15 2TT, U.K.
2 TWI, Abington Hall, Abington, Cambridge CB1 6AL, U.K.
Diffusion bonding of the intermetallic compound Ti-48A1-2Mn-2Nb has been carried out in order to determine what effect temperature, time and starting base microstructure have on the bond line microstructure, in particular the extent of grain growth that occurs at the interface. The results showed that the non-equilibrium lamellar and duplex microstructures gave more grain growth at the interface compared with the equilibrium fully γ microstructure for bonding upto 45 minutes in the temperature range 1200°C-1350°C . It was also observed that the base microstructure in the duplex and fully γ samples was little changed during bonding, whereas in the lamellar samples decomposition of the lamellar (α2+γ) regions to allotriomorphic γ occurred, particularly at 1250°C.
© EDP Sciences 1993