TOOL FOR FRICTION STIR WELDING AND METHOD FOR FORMING

摘要

PURPOSE: A tool for friction stir welding and a molding method thereof are provided to prevent the abrasion of a welding tool caused by chemical reaction to a work piece because the welding tool is made from silicon nitride sintered in a high-pressure gas atmosphere. CONSTITUTION: A tool for friction stir welding is manufactured by sintering silicon nitride powder, whose grain size is 0.3μm or less, in a high-pressure gas atmosphere. The welding tool comprises a tool body(10), a shoulder part(20) that is projected from both ends of the tool body and have a slope surface(22) inclined outward, and a fin part(30) that is projected from the center of the shoulder part to contact a welded part at the time of friction stirring.