Abstract
A new process for tube ironing, the "Planetary Conical Rolling" (PCR) process, is proposed. A number of rollers rotate around the cone while revolving around their respective axis, preventing sliding friction which is the main cause of galling and breakage in the conventional ironing process. Additionally, a large deformation and a high pressure can be applied locally to the material under each roller because this process is an incremental process and the axis support cone is highly rigid. Taking advantage of these features to produce a hybrid tube, lap pressure welding by PCR process between aluminum alloy (A5052) and pure copper (Cl100) was discussed in this paper. From the measurements of bonding strength, it was found that the relative strength of outer tube against inner tube mainly affected the bonding strength. That is, high bonding strength was obtained when the relative hard tube was set on the inner side. This is explained by the difference of plastic zone in both tubes depending on the material combinations.
