A novel severe plastic deformation method for manufacturing Al/Mg bimetallic tube

摘要

A new severe plastic deformation for manufacturing Al/Mg bimetallic tube called the TES (tube extrusion shearing) process, which combines direct extrusion with two-step shearing, has been developed to manufacture Al/Mg bimetallic tube. Load evolution with stroke at different temperatures has been simulated by establishing three-dimensional finite element simulation of the TES process of Al/Mg bimetallic tubes. To explore the deformation mechanisms of the Al/Mg bimetallic tube during the TES process, the microstructures and phase compositions and microhardnesses of the bonded layer have been observed and analyzed. A higher extrusion temperature would decrease the extrusion loads. Defects of bonding layer appear less if the extrusion temperature is higher, and the bonding layer of the bi-metal tube has better quality. Three eutectic compounds, Mg2Al3, MgAl, and Mg17Al12, can be formed in the interface transition zone. The average hardness of the bonding layer is very high. The results indicate that the TES process can produce large plastic deformation and manufacture Al/Mg bimetallic tube and improve the bonding layer.