In this work, three types of probeless tools (archimedes, involute, and concave tools) were designed. A 7075-T651 sheet of 1.0 mm thickness was welded using the designed probeless tools. It was found that the stir zone and hook defect varied a lot for different joints. Plunge depth was the dominant process parameter for joint property. The joint’s maximum failure load (5.73 kN) was obtained with the concave tool when the target plunge depth was 0.55 mm. Two typical joint fracture modes (shear fracture and plug fracture) were found using three designed tools with different plunge depths, rotation speeds, and dwell times. Shoulder geometry presented little influence on heat generation. Compared with involute grooves, archimedes grooves showed to be more effective on the material flow. The properties of the joints with the archimedes tool were more sensitive to welding parameters. Compared with the flat tool, the concave tool decreased the escape of plasticized material, improved the forge force, and optimized the metallurgical bond at the interface.

中文翻译：

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肩部几何形状对无探针搅拌摩擦点焊铝7075-T651板材的组织和力学性能的影响

在这项工作中，设计了三种类型的无探针工具（拱形，渐开线和凹入工具）。使用设计的无探针工具焊接厚度为1.0 mm的7075-T651板。发现搅拌区和钩缺陷对于不同的接头变化很大。切入深度是决定接头性能的主要工艺参数。当目标插入深度为0.55 mm时，使用凹形工具可获得接头的最大破坏载荷（5.73 kN）。使用三种设计的工具（具有不同的切入深度，旋转速度和停留时间）发现了两种典型的接头断裂模式（剪切断裂和塞子断裂）。肩部几何形状对热量产生的影响很小。与渐开线槽相比，阿基米德槽对材料流动更有效。使用阿基米德工具的接头的属性对焊接参数更敏感。与扁平工具相比，凹形工具减少了增塑材料的逸出，提高了锻造力，并优化了界面处的冶金结合。