VIBRATION FUSION JOINING METHOD

摘要

PURPOSE:To improved the joint rigidity of the beads extending almost perpendicularly to the vibration direction while controlling the occurrence of burrs by a method wherein the width of the fusion joint face of a vertical bead is made greater than that of the fusion joint face of a horizontal bead which the vertical bead intersects. CONSTITUTION:An upper member 2 is placed on top of a lower member 1 and pressed into contact therewith. The upper member 2 is then excited into axial vibrations to form a vibration fusion joint therebetween. In the initial stage, since a pressure application force per unit area is microscopically greater on the part in contact width l2 than on the part in contact with width l1, fusion joints are first formed between a first lower horizontal bead 31 and a first upper horizontal bead 41 and between a second lower horizontal bead 33 and a second upper horizontal bead 43 at their respective contact parts. Since a major part of the pressure application force is transmitted to an unmolten part in contact with the width l1, fusion joints are then formed between a first lower vertical bead 30 and a first upper vertical bead 40 and between the beads 33 and 43 at their respective contact parts. When the excitation of the vibrations is stopped, the fusion parts are solidified to complete the formation of the vibration fusion joints.