Characterization of composite laminate with copper and AISI304 made by a diffusion bonding process

Abstract

The composite laminate assembly was made by stacking alternate layers of AISI304 and copper foils. The copper and AISI304 foils of 0.1 mm thick were placed one above the other and during diffusion bonding experiments. The bonding parameter temperature was varied as 850, 900 and 925 ⁰C, constant pressure of 4 MPa, and bonding time of 60 min was maintained for all the experiments. The laminated joints were characterized by optical, scanning electron microscopy for grain size measurement and phase identification. Electron microprobe analysis (EPMA) was performed at the joint region for elemental analysis across the interface and into the base metals. At the AISI304 base metal side a maximum hardness of 342.6 VHN and at the copper base metal side, it was 152.5 VHN. For the sample bonded at 925 ⁰C, the shear strength was a maximum of 72.8 MPa. X-Ray Diffraction Analysis (XRD) revealed the presence of phases γ-Fe and γ-Cu, and intermetallic compounds such as FeCu 4 , Cu 2 CrNi, sigma (σ)-phase and oxide CuO.