Preliminary Investigations on Preparation of Cu-Al Bi-Metallic Tubes Using Swaging-Diffusion Method

Abstract

Bi-metallic tubes (BMTs) combine performance advantages of two different tubes and are usually used in particular conditions where corrosion resistance is important. Traditionally, BMTs are manufactured by plastic processes such as extrusion, explosive welding/cladding, hydroforming and even combinations thereof. However, rotary swaging, which is commonly used to produce tubes, was seldom mentioned when preparing BMTs. In this work, Cu-Al BMTs were achieved using swaging-diffusion method (SDM). The effect of process on formability of BMTs are investigated. The experimental results indicate that with the increasing of deformation, metallurgical bonding layer, which is more desirable than mechanical bonding layer, can be achieved. And the metallurgical bonding layer will thicken to 2μm after diffusion. Besides, some failures produced in the swaging process are presented.