A study on the process of joining by Joule heat generated in metal powder inserted between two metal bars

Electric resistance welding and arc welding are most important and useful processes among many welding processes for industrial activity. In this study, a new process of electric resistance welding was considered. The process uses Joule heat generated in metal powder inserted between a pair of solid bars. A method of joining materials was examined. The purpose of the present study is that the joining of two kind materials, which have different melting point, is performed by using metal powder as insert material. The unique point of present process is to insert the metal powder between the two solid metals. During the joining, the melting powder metal was diffused into the solid materials. For the joining, the industrial resistance pressure-welding machine was used as an electric current power source. During the joining, the materials were compressed by hydraulic testing machine. The effectiveness of the present study is confirmed by joining two pure-aluminum bars. The joined materials were broken at the solid aluminum, and the tensile strength of the joined material was the same level as the annealed pure-aluminum. From the observation of macroscopic feature of the joint section, the large size of defect, such as void, was not observed. It is concluded that the present method may be applied to the joining of the different materials.