Optimization of shape of workpieces for net shape forming using pressure welding by finite element simulation

For net shape forming using pressure welding without machining after joining, shapes of workpieces were optimized by simulations of metal flow using a finite element method. Round bars having taper cut and concave arc cut shapes were dealt with for the simulation of pressure welding. It was found from the simulations that arc cut shape makes an initial joining surface expand into a whole joining area and that the joining surface expansion is controlled by means of a diameter of the initial joining surface. Aluminum round bars provided with a concave arc cut edge were experimentally pressure welded at room temperature and it was found that a joint formed at the joining surface expansion more than 5 times has a bond strength more than a tensile strength of the base metal. It was concluded that the concave arc cut shape is a suitable edge shape for the pressure welding.