A novel spin-bonding process for manufacturing multilayered clad tubes

Utilizing the so-called tube spinning, a cold-bonding process entitled as “spin-bonding” is developed to produce seamless thin-walled clad tubes and cylinders. By this method, two layers of AA 1050 tubes were successfully bonded together to form a clad tube at room temperature. Based on mechanical aspects of the tube spinning process, the mechanism of spin-bonding is explained in two stages: surface preparation before occurrence of a stable bond and bond strengthening thereafter. The effects of process temperature, thickness reduction, feed rate and roller attack angle as the parameters of tube spinning on the bond strength are studied. It is shown that the bond strength increases by increasing the thickness reduction and process temperature. It is also observed that the bond strength is not considerably affected by the feed rate and roller attack angle, especially at high thickness reductions. The SEM micrographs of the peel surfaces illustrate that at high temperature, both of area fraction and number of bond spots increase and their inter-distances decrease.