Microstructural Characterization of Pure Copper Tubes Produced by A Novel Method Friction Stir Back Extrusion

A novel method by name friction stir back extrusion was applied to produce pure copper tubes from solid cylindrical specimens. A cylindrical copper specimen was kept inside the hole in a die and extruded by plunging the rotating tool. The microstructure of the produced copper tube was studied using optical microscopy. The microstructure was found to be homogeneous along the tube. The trapped frictional heat coarsened the grains. The results prove that friction stir back extrusion process is capable of producing sound copper tubes. (C) 2014 Elsevier Ltd.