Interfacial reaction products formation in the diffusion bonded joints made between Ti-6Al-4V and AISI 304L with brass interlayer

Abstract

Abstract In the diffusion bonded (DB) joints, two interfaces exist, one between the base metal Ti-6Al-4 V and brass interlayer, and the second one between the brass interlayer and base metal AISI 304L stainless steel. The interfacial reaction products formed at the interfaces were examined with optical, scanning electron microscope (SEM), energy dispersive X-ray diffraction analysis (EDAX). Diffusion bonding (DB) experiments were carried out in the temperature range of 800–850 ⁰C with an interval of 25 ⁰C, holding time 60, 90 and 120 min, and under pressures 4 and 8 MPa. Maximum tensile strength of 218 MPa was realised for the samples processed at 850 ⁰C, 60 min, and 8 MPa. At the interface between T-6Al-4 V and brass the maximum hardness values of 548.2 VHN was realized for the sample bonded at 850 ⁰C. The XRD performed at the fracture site, indicated the presence of intermetallic compounds such as CuTi, CuTi2, Cu5Zn8, Fe22Zn78, gamma (ϒ) and sigma (σ) phases and pure ‘Cu’.