An investigation of bimetallic tube fabrication through a novel friction stir extrusion based technology for automotive applications

Abstract

The bimetallic tubular component fabrication through a novel friction stir backward extrusion (FSBE) process has been proposed in this article. During the extrusion process, the bonding occurs between the substrate and cladding material due to diffusion. The frictional heat generated during the process leads to softening and extrusion of solid clad material that forms a layer on the substrate material. Different sets of materials have been used for feasibility testing. The results show that the process is capable of uniform cladding and void-free bonding for different sets of material. Energy dispersive spectroscopy (EDS) line scan and area mapping were performed at the interface to understand the diffusion pattern. At the interface, intermetallic compounds (IMCs) were confirmed via spot EDS and X-ray diffraction (XRD) analyses. Strong metallurgical bonding occurs between the substrate and the cladding material due to the interdiffusion of the materials, and the flattening test was performed to check the bonding efficacy. Thus, this process opens new opportunities for the fabrication of bimetallic tubular components, which can be used in electrical, structural, lightweight, and corrosion-resistance applications.