Characteristics of friction welding within a short time for aluminum alloy deformed by ECAE process

Abstract

Abstract In order to obtain high-strength materials, several plastic deformation processes such as ECAE (equal channel angular extrusion) process is effective. However, it is hard to produce a workpiece with elongate workpiece because the dimensions of dies for ECAE process influence the shape of the workpiece. Therefore, one of the best approaches for elongated shape is welding. The friction welding is the most appropriate method without distortion of deformed microstructure by ECAE. The aim of this study, in order to improve the joint efficiency, the friction welding for the aluminum alloy deformed by ECAE is carried out in very short welding time. The workpiece material was A6063-T5. The ECAE process was carried out at room temperature by means of the dedicated device that developed by one of authors, and the workpieces were deformed by ECAE repeatedly up to 3rd passes. After ECAE, the friction welding process was carried out In these process, the upset pressure was same as heating pressure. The heating time by friction was within 1 sec. The joint efficiencies of all pressure condition were over 70% from results of tensile tests, and the point of fracture was joint zone on all condition. The friction welding within a short time is beneficial for joining of materials deformed by multiple passes of ECAE.