In the present study, the weld formation and mechanical properties of the AA-5A06 friction pull plug welded (FPPW) joints were improved by controlling the axial force history. Several defect-free FPPW joints were made successfully by using the welding parameters of 15–20 kN/s axial loading rate, 20–30 kN axial welding force and 6–7 mm axial feeding displacement. The results indicated that using higher axial loading rate and axial welding force produced more stable heat generation and shorter frictional heating time between the frictional interface. In this case, the plastic flow of the materials around the hole could be further improved since the axial feeding displacement of the plug was increased. The maximum ultimate tensile strength (UTS) and elongation of the FPPW 5A06 joints were 314 MPa and 4.8%, respectively. The thermal mechanically affect zone (TMAZ) had the lowest hardness value throughout the joint and was found as the fracture location to all the tensile samples. The softening of TMAZ was mainly caused by the weakening of the cold work hardening and the coarsening of grains.

中文翻译：

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通过轴向力控制改善AA-5A06摩擦拉拔焊缝的焊接成形和力学性能

在本研究中，通过控制轴向力历程来改善AA-5A06摩擦拉塞焊接（FPPW）接头的焊缝形成和力学性能。通过使用15–20 kN / s的轴向加载速率，20–30 kN的轴向焊接力和6–7 mm的轴向进给位移，成功地制作了几种无缺陷的FPPW接头。结果表明，使用较高的轴向载荷率和轴向焊接力可产生更稳定的热量，并缩短摩擦界面之间的摩擦加热时间。在这种情况下，由于增加了塞子的轴向进给位移，因此可以进一步改善材料在孔周围的塑性流动。FPPW 5A06接头的最大极限抗拉强度（UTS）和伸长率分别为314 MPa和4.8％。热机械影响区（TMAZ）在整个接头中具有最低的硬度值，并且被发现为所有拉伸样品的断裂位置。TMAZ的软化主要是由于冷作硬化的减弱和晶粒的粗化引起的。