CFRTP/Al非接触超声辅助激光连接工艺研究  

Study on CFRTP/Al non-contact Ultrasonic Assisted Laser Joining Process

作　　者：刘敬元 王琦 韩东志 张博宇 贾振元[1] 王福吉[1] LIU Jingyuan;WANG Qi;HAN Dongzhi;ZHANG Boyu;JIA Zhenyuan;WANG Fuji(Key Laboratory for Precision and Non-Traditional Machining Technology of the Ministry of Education,School of Mechanical Engineering,Dalian University of Technology,Dalian 116024)

机构地区：[1]大连理工大学机械工程学院精密与特种加工教育部重点实验室,大连116024

出　　处：《纤维复合材料》2021年第2期3-8,共6页Fiber Composites

基　　金：国家自然科学基金(52005077);中央高校基本科研业务费;辽宁省“兴辽英才计划”项目(XLYC1902014,XLYC1801008,XLYCYSZX1901)

摘　　要：碳纤维增强热塑性复合材料(CFRTP)与铝合金(Al)组成的叠层结构广泛应用于航空航天、汽车等领域,实现CFRTP/Al叠层的非破坏、高可靠连接是保证装备使役性能的关键。激光连接技术以其能量密度集中、效率高、易于实现自动化等优点已成为CFRTP/Al异种材料连接的热门技术,但CFRTP对温度敏感,在激光连接时易过热分解产生孔隙,接头固化后孔隙存留在接头内形成缺陷显著降低了接头性能。超声辅助激光连接通过在金属侧以接触形式施加超声,有效减少了接头内孔隙。但对于CFRTP/Al叠层,由于CFRTP透光性差,激光需从金属侧施加,超声若以接触形式施加于CFRTP侧,超声的高频振动会使工件各接触面剧烈摩擦,产生大量热量,从而加剧接头的热损伤,进而降低接头性能。本文研究了非接触超声辅助激光连接工艺,对比了不同超声施加形式下的接头外观与接头性能,并进一步分析了工艺参数对接头性能的影响,发现以非接触形式施加超声后接头性能最大约为3kN,相比未施加超声接头的性能提高了约1倍,接头性能提升效果随超声作用距离增大而降低,随超声频率增大而增大,但超声频率约为26 kHz时提升效果降低。The laminated structure composed of carbon fiber reinforced thermoplastic composite(CFRTP) and aluminum alloy(Al) is widely used in aerospace, automobile and other fields. The key to ensure the service performance of equipment is to realize the non-destructive and highly reliable connection of CFRTP/Al stack. Laser joining technology has become a popular technology for joining CFRTP/Al dissimilar materials because of its advantages of concentrated energy density, high efficiency and easy automation. However, CFRTP is sensitive to temperature, and it is easy to overheat and decompose to produce pore. Defects caused by pore remaining in the joint after curing significantly reduce the joint properties. Ultrasound-assisted laser joining reduces pore in the joint by applying ultrasound in contact on the metal side. However, for CFRTP/Al stacks, laser light is applied from metal side due to poor transmittance of CFRTP. If ultrasound is applied to CFRTP side in contact form, high-frequency vibration of ultrasonic will cause severe friction on all contact surfaces of workpiece and generate a lot of heat, thermal defects in the joint will be aggravated and joint properties will be reduced. In order to solve this problem, this paper studied the non-contact ultrasonic-assisted laser joining technology, compared the joint appearance and joint properties under different ultrasonic application forms, and further analyzed the influence of process parameters on joint properties. It was found that the joint properties after non-contact ultrasonic application is up to 3104 N, compared with the joint without ultrasonic, the properties of the joint is improved about 1 times. The joint performance improvement effect decreases with the increase of ultrasonic distance and increases with the increase of ultrasonic frequency, However, when the ultrasonic frequency is 26 kHz, the increase effect is reduced.

关 键 词：超声辅助激光连接 非接触超声辅助激光连接 CFRTP 铝合金 接头性能 

分 类 号：TG496[金属学及工艺—焊接]