from the conferences organized by TANGER Ltd.
Titanium and AISI 304 stainless steel were joined using a 0.1 mm thick aluminum foil interlayer at temperatures of 550, 650 and 700 °C for 1 h under 2 MPa pressure in vacuum. The interface microstructures of the bonded samples were observed using the optical and scanning electron microscopes. The chemical analysis was performed with energy dispersion spectroscopy. The effect of bonding temperature on joints microstructure, composition and microhardness was investigated. FeAl3 and Fe2Al5 intermetallic layers were observed at the stainless steel/aluminum interfaces. At the aluminum/titanium interfaces TiAl, TiAl2 and TiAl3 intermetallic layers were identified. The width of intermetallic layers for both interfaces increased gradually with the increase in bonding temperature. The irregular shaped particles of Al7Cr were additionally observed in aluminum matrix for joints that were transient-liquid-phase bonded at 700 °C. Microhardness of joints achieved values from 220 to 870 HV and was higher than that one for base metals. The microhardness values for analogous intermetallic layers increased with increasing temperature of bonding.
Keywords: titanium, stainless steel, aluminum, diffusion bonding, TLP joining, microstructure© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.