In the present study, the effect of cone angle of tool pin on the mechanical properties and microhardness properties of aluminum alloy AA6061-T6 specimens is investigated for three processes of SFSW, symmetric DFSW, and asymmetric DFSW. In each of the mentioned welding processes, tools with 5 different conical angles of 0, 5, 10, 15, and 20° are used. In these three welding processes, the mechanical properties of the final welded joint with conical tools have been enhanced noticeably compared to the tool with simple cylindrical pins (0° angle). Based on the obtained results, it was found that the joints obtained from asymmetric DFSW, symmetric DFSW, and SFSW had the best mechanical properties, respectively. The optimum cone angles for tool pin in SFSW, symmetric DFSW, and asymmetric DFSW processes were equal to 15, 10, and 10°, respectively. In addition, it was concluded that the welded specimen through the asymmetric DFSW with the cone angle of 10° attained the closest mechanical properties to the base (parent) metal. The parameters of YS, UTS, and E% in this sample were 78.3%, 84.8%, and 86.4% of the base sample, respectively.

中文翻译：

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SFSW和DFSW圆柱销锥角对AA6061-T6合金力学性能的影响

在本研究中，针对 SFSW、对称 DFSW 和非对称 DFSW 三种工艺，研究了工具销锥角对 AA6061-T6 铝合金试样力学性能和显微硬度性能的影响。在每个提到的焊接过程中，使用具有 0、5、10、15 和 20° 5 个不同锥角的工具。在这三种焊接工艺中，与使用简单圆柱销（0°角）的工具相比，使用锥形工具的最终焊接接头的机械性能得到了显着提高。根据获得的结果，发现由非对称 DFSW、对称 DFSW 和 SFSW 获得的接头分别具有最好的机械性能。SFSW、对称 DFSW 和非对称 DFSW 工艺中工具销的最佳锥角分别等于 15、10 和 10°。此外，得出的结论是，通过锥角为 10° 的非对称 DFSW 的焊接试样获得了与母材（母材）最接近的机械性能。本样本中 YS、UTS 和 E% 的参数分别为基础样本的 78.3%、84.8% 和 86.4%。