摘要: |
搅拌摩擦焊在铝/钛异种金属焊接方面具有明显优势,但采用常规搅拌摩擦焊进行铝/钛异种金属焊接时,在焊缝根部仍易产生弱连接缺陷。为此,采用超声振动强化搅拌摩擦焊接新工艺进行了4mm厚的2024铝合金与TC4钛合金的焊接工艺试验,焊后进行了接头微观组织与力学性能分析。通过与常规搅拌摩擦焊接工艺进行对比,发现辅加超声振动能够改善铝/钛异种金属搅拌摩擦焊缝表面成形,降低接头根部弱连接缺陷的高度,减少接头金属间化合物的生成。在搅拌头转速为400r/min,焊接速度为45mm/min时,接头的抗拉强度可达到343.3MPa,相比于常规搅拌摩擦焊提升18.9%,达到铝合金母材强度的76.2%。研究证实了超声振动强化搅拌摩擦焊接新工艺在铝/钛异种金属焊接方面的优势,为提高铝/钛异种金属的焊接质量提供了新的技术手段。 |
关键词: 超声振动强化搅拌摩擦焊;铝/钛异种焊;焊缝成形;金属间化合物层;超声辅助 |
基金项目:国家自然科学基金项目(522**349、520**005);山东省重点研发计划(重大科技创新工程)项目(202****X1)。 |
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Experimental Study on Ultrasonic Vibration Enhanced Friction Stir Welding of Al/Ti Dissimilar Joints |
Zhang XiankunShi LeiWu ChuansongLi Shengli
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MOE Key Lab for Liquid-solid Structure Evolution and Materials Processing, Shandong University, Jinan 250061
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Abstract: |
Frictionstirwelding (FSW) has significant advantages in the welding of Al/Tihybridstructure. However, the kissing bond defects are still prone to occur at the weld root when using conventional FSW for joiningAl/Tihybrid structure. Therefore, a novel ultrasonic vibration enhanced friction stir welding (UVeFSW) was employed for joining of 4mmthick 2024 aluminum alloy and TC4 titanium alloy. The microstructure and mechanical properties of the joints were analyzed. It was found that UVeFSW can improve theweld formation, reduce the height of kissing bond defects at the weld root, and inhibit the formation of intermetallic compounds in the Al/Ti interface. The average tensile strength of the UVeFSW joints reached its maximum value of 343.3MPaat the tool rotation speed of 400r/minwith the welding speed of 45mm/min. The maximum tensile strength of UVeFSW joint is about 18.9% higher than that of conventional FSW joint. The maximum tensile strength of the UVeFSW joint reaches about 76.2% of the tensile strength of 2024 aluminum alloy.It proves that the novel UVeFSW is suitable in joining of Al and Ti dissimilar alloy, providing a new joining technology for achieving high-quality Al/Ti dissimilar joints. |
Key words: ultrasonic vibration enhanced friction stir welding (UVeFSW);Al/Ti dissimilar welding;weld formation;intermetallic compounds layer;ultrasonic assisted |