Abstract Al/Ti dissimilar welds were fabricated by ultrasonic vibrations assisted friction stir welding, which eliminated the tool wear and enhanced the material flow. The peak temperature was lowered, and a pre-heating period was introduced into welding by ultrasonic vibrations. Wider interface and smaller grain structures were observed in the welds due to the reinforced material flows. Ti fragments were spun into the Al alloy, resulting in a mixing zone beside the interface. Atomic diffusion was also enhanced with ultrasonic vibrations, according to the element maps. The strength of the Al/Ti welds was doubled with the influence of ultrasonic vibrations. The fracture was nucleated at the interface and propagated into the base materials. Shear dimple was the dominant characteristic of the fracture morphology, whereas cleavage planes were also found.

中文翻译：

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超声振动对Al/Ti搅拌摩擦搭接焊缝组织和力学性能的影响

摘要 采用超声振动辅助搅拌摩擦焊制备Al/Ti异种焊缝，消除了工具磨损，增强了材料流动。降低峰值温度，并通过超声波振动在焊接中引入预热期。由于增强的材料流动，在焊缝中观察到更宽的界面和更小的晶粒结构。钛碎片被旋入铝合金中，在界面旁边形成一个混合区。根据元素图，超声波振动也增强了原子扩散。在超声波振动的影响下，Al/Ti 焊缝的强度增加了一倍。断裂在界面处成核并扩展到基材中。剪切凹坑是断裂形态的主要特征，