The groove shape of the weld faying part was investigated to obtain an ideal pipe friction-welded joint that had a fracture in the base metal and no inner flash of it. The steel pipe had inner and outer diameters of 8.0 mm and 13.5 mm, respectively, and the weld faying surface was of a basic flat shape (butt) type. Moreover, stepped and tapered groove shapes were prepared. Pipe groove shapes were welded with a friction speed of 27.5 s⁻¹ and a friction load of 2.79 kN. Joining phenomena during the welding process were observed, and the tensile strength of joints was evaluated. The joints, that fabricated with flat or step groove shapes, made with a friction time at which the friction torque reached the initial peak did not have the tensile strength of the base metal nor a fracture in the base metal. However, the joints fabricated with a friction time that reached past the initial peak had a large flash, and they contained a fracture in the base metal. In contrast, when joints were made with a gently tapered groove shape with a friction time reaching the time of the initial peak, they achieved a fracture in the base metal, despite having an extremely small inner flash. Therefore, the shape at the weld faying part was capable of reducing the flash exhausted from the weld interface.

中文翻译：

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焊缝搭接槽形状对减少摩擦焊钢管接头内溢边的影响

研究了焊接搭接部的凹槽形状，以获得理想的管道摩擦焊接接头，该接头的母材断裂且内部没有飞边。钢管的内径和外径分别为8.0mm和13.5mm，并且焊接搭接面为基本平坦的形状（对接）型。此外，制备了阶梯状和锥形凹槽形状。以27.5 s ^-1的摩擦速度焊接管槽形状摩擦载荷为2.79 kN。观察焊接过程中的接合现象，并评估接头的拉伸强度。以平坦的或阶梯状的凹槽形状制造的接头，在摩擦时间达到初始峰值的摩擦时间下，不具有母材的拉伸强度或母材的断裂。然而，以超过初始峰值的摩擦时间制造的接头具有大的飞边，并且它们在母材中包含断裂。相反，当将接头制成具有逐渐变细的凹槽形状且摩擦时间达到初始峰值的时间时，尽管内部溢料非常小，但接头仍会发生母材断裂。因此，焊接搭接部处的形状能够减少从焊接界面排出的飞边。