为解决传统搅拌摩擦焊接过程中的焊缝减薄问题，以轨道交通领域常用的6082-T6铝合金作为研究对象，从轴肩下压量为零的角度出发，通过轴肩端面圆形内凹槽及搅拌针周向螺纹复合三铣平面的设计，获得了无减薄且成形良好的焊接接头. 结果表明，当焊接速度一定时，转速的增加可提高焊接热输入，抑制焊缝缺陷的产生. 相较于转速400, 600 r/min下的接头可焊区间得到了有效拓宽，焊接速度最高可达400 mm/min；焊接过程的热循环受焊接速度与转速的耦合作用. 焊接热循环过大，焊缝易出现粗大组织，影响焊接接头的强度. 在转速600 r/min、焊接速度500 mm/min的参数下，接头抗拉强度达254 MPa，为母材强度的80%.
Based on the "zero plunge depth" concept, a tapered threaded pin with triple facets and a shoulder with a circular groove were designed to solve the weld-thinning problem in the friction stir welding of 6082-T6 aluminum alloy used in the railway fields. The results indicated that the increase of the rotational speed could increase the heat input and inhibit the formation of the defects when the welding speed was constant. Compared with the parameter of 400 r/min, the process window at 600 r/min was effectively broadened, and the welding speed could reach 400 mm/min. The heat input was under the coupling effect of welding speed and rotational speed. The welding joint was prone to coarse microstructure under the high heat input, which affected the strength of the welded joint. Under the rotational speed of 600 r/min and the welding speed of 500 mm/min, the tensile strength of the joint reach 254 MPa, reaching 80% of the base material.
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