Abstract: A friction stir welding device, provided for welding stacked metallic boards together, includes a mounting seat and a plurality of friction-stir tools. The mounting seat is defined with a rotational axis-direction. Each friction-stir tool has a shoulder portion and a stirring probe protruded from the shoulder portion. The friction-stir tools are arranged in the rotational axis-direction and disposed on a bottom surface of the mounting seat. The friction-stir tools can rotate along the rotational axis-direction. When a relative linear motion is applied between the friction-stir tools and the stacked metallic boards, the shoulders of the friction-stir tools produce stirring-coverage zones which are overlapped partially along the linear movement direction, so that the stirring-coverage zones by the friction-stir tools form a planar welding zone. The present disclosure also provides a method of friction stir welding for welding stacked metallic boards together.

Abstract: A heat-dissipating device includes a base and a plurality of heat-dissipating members. The base is formed with a plurality of joint holes. Each heat-dissipating member has an inserting section and an exposed section connected with the inserting section. The inserting sections are inserted into the joint holes in a close fit manner, respectively. The exposed sections are exposed outside a top surface of the base. The ends of the inserting sections and the bottom surface of the base are welded by a friction stir welding (FSW) manner with a solid-state joining structure. The present disclosure also provides a method for manufacturing a heat-dissipating device, which joins the ends of the inserting sections and the bottom surface of the base by a friction stir welding manner.