The working principle of friction stir welding is: During welding, the stirring head composed of the shaft shoulder and the stirring needle rotates and inserts the workpiece until the shaft shoulder contacts the workpiece, and the friction between the shaft shoulder and the stirring needle (mainly the shaft shoulder) and the workpiece produces a lot of friction The friction heat makes the metal around the stirring head plasticize, and at the same time, under the action of the stirring head, the metal in the front of the stirring head is transferred to the rear of the stirring head, and then the friction stir weld is formed by pressing and forging of the shaft shoulder. The stirring head is the core component of friction stir welding. The geometry and material selection of the stirring head is very important to the performance of the workpiece joint. Tool and die steel mixing heads are generally used to weld light alloys such as aluminum and magnesium alloys. The tungsten rhenium alloy stirring head has excellent high temperature strength, toughness, and wear resistance, which can meet the needs of friction stir welding of steel, titanium, copper alloy and other materials.