Revista de ciencias e ingeniería de materiales

Microstructure Evolution and Brazing Mechanism of Ti2SnC-Ti6Al4V Joint by Using Cu Pure Foil

Abstract

Yu W

The MAX phase Ti2SnC was successfully welded to Ti6Al4V (TC4) through Cu interlayer in Ar atmosphere at low temperature 750ºC, during 1h under an applied mechanical pressure 10 MPa. The results indicated that the outward diffusion of Sn from Ti2SnC played a critical role in the chemical composition of joints. After 60 mins, the reaction layers consist of five zones: interleaved β-Cu(Sn) and α-Cu(Sn) zone zone (V), enriched Sn and CuTi0.5Sn0.5 intermetallic phase (IV), poor Sn, Ti and rich Cu zone (III), Ti3Cu4 intermetallic (II) and β-Ti (Cu) phase (I). Shear test results showed that the average shear strength reached 85.7 ±10 MPa. Corresponding fractographs indicated that the crack mainly propagated along Ti2SnC substrate adjacent to the bonding zone, accompanied with an intergranular fracture mode.