| 摘要 |
PROBLEM TO BE SOLVED: To provide a rotary tool for joining used for friction stir joining of steel.SOLUTION: A friction stir welding tool comprises a substantially cylindrical shank 2. The shank 2 comprises a pin 3 of a smaller diameter projecting on one end 5, starting from a shoulder region 4 of the shank 2. The friction stir welding tool is configured, at least in a region of the pin 3 and in the shoulder region 4, of hard metal containing 80 wt% to 98 wt% of tungsten carbide having average grain size of more than 1 μm and up to 20 wt% of cobalt and optionally, in sum, up to 18 wt% of titanium carbide, tantalum carbide, niobium carbide and/or mixed carbide thereof. The friction stir welding tool comprises coating consisting of one or more layers in at least one of the regions. |
