【摘要】 自主研制静止轴肩搅拌摩擦焊(SSFSW)焊具,并且成功应用于高强铝合金2219-T6的焊接。当静止轴肩相对深压与搅拌针根部的小轴肩形成"内浅外深"的状态时,更能充分发挥SSFSW的作用。对接头焊缝成形、显微组织、显微硬度及拉伸性能分别开展了试验研究。结果表明:SSFSW消除了焊缝减薄问题,以搅拌针起主要的搅拌作用有效地减小了焊缝宽度在板厚方向上的差异,减小了热机影响区和热影响区的范围。在恒定焊接转速800转/min的条件下,当焊接速度增大到300mm/min时,接头抗拉强度达到354MPa(母材的79.6%),拉伸断裂发生在焊缝后退侧的热机影响区边缘。更多还原

【Abstract】 In this paper, a tool system for the stationary shoulder friction stir welding was self-designed and applied successfully to weld the high-strength aluminum alloy 2219-T6. When the plunge depth of the stationary shoulder was larger than that of the sub-size concave shoulder at the root of the tool pin, the SSFSW could exert its greatest effects. The researches of weld formation, microstructures, hardness distribution and tensile properties of the welded joints were conducted. The phenomenon of weld thinning was eliminated completely through the SSFSW process. The stirring effect was mainly caused by the tool pin, thus the variation of weld width was obviously reduced along the thickness direction. Meanwhile, both the thermo-mechanically affected zone(TMAZ) and heat-affected zone were decreased. At a constant rotation speed of 800 rpm, the tensile strength reached 354 MPa(79.6% of the base material) when the welding speed increased to 300 mm/min, and the tensile fracture occurred at the edge of the TMAZ on the retreating side.更多还原