Strength Characteristics on the Diffusion Bonded Joint of Intermetallic Compound TiAl and Structural Steel

Abstract

In this research, diffusion bonding of the intermetallic compound TiAl containing Fe, V, B and SACM645 steel was investigated. Relationships between strength characteristics and bonding parameters were analyzed. Main results obtained are as follows,
(1) Direct diffusion bonding of TiAl and SACM645 was possible, high strength joints were obtained by selecting short bonding time with the bonding temperature in the range of 1223-1283K.
(2) In the bonding interface, two or three inter-layers were formed as diffusion process proceeded. Decarburized layer at the steel side, Fe-Al-Ti type layer and TiC layer at the TiAl side were formed.
(3) High strength joints were obtained by suppressing the formation of TiC compound in the bonding interface and by controlling total width of inter-layers within 5μm.