CF/PEI复合材料超声焊工艺优化及机理研究  

Optimization and mechanism of ultrasonic welding process of CF/PEI composite

作　　者：王静 贾松[1,2] 袁媛 夏蕾 王富帅 任荣 熊需海 WANG Jing;JIA Song;YUAN Yuan;XIA Lei;WANG Fushuai;REN Rong;XIONG Xuhai(School of Materials Science and Engineering,Shenyang Aerospace University,Shenyang 110136,China;Liaoning Key Laboratory of Advanced Polymer Matrix Composites,Shenyang Aerospace University,Shenyang 110136,China;China Wuzhou Engineering Group Co.,Ltd.,Beijing 100053,China)

机构地区：[1]沈阳航空航天大学材料科学与工程学院,沈阳110136 [2]沈阳航空航天大学辽宁省先进聚合物基复合材料重点实验室,沈阳110136 [3]中国五洲工程设计集团有限公司,北京100053

出　　处：《材料工程》2023年第7期42-49,共8页Journal of Materials Engineering

基　　金：国家自然科学基金项目(51403129,51873109);辽宁省兴辽英才计划项目(XLYC1907019,XLYC1907198);辽宁省教育厅面上项目(LJKZ0171)。

摘　　要：碳纤维复合材料(CFRP)广泛应用于航空航天领域,高效连接技术是影响CFRP构件制造成本和使用安全的关键因素之一。利用超声焊技术对碳纤维增强聚醚酰亚胺树脂基复合材料(CF/PEI)进行焊接,采用单搭接剪切强度(LSS)测试研究了超声焊接压力和焊接时间对复合材料超声焊接头强度的影响,利用扫描电镜对断面微观形貌进行表征;并对实验数据进行线性拟合分析,结合BP神经网络与遗传算法对时间和压力参数进行优化并预测接头强度;最后研究了保压时间对接头强度的影响机理。结果表明:当焊接时间为2.5 s,焊接压力为0.45 MPa时,LSS达到最大值为25.6 MPa,较高的焊接强度是由于接头表面形成致密稳定的结构所致;BP神经网络将实验数据细化,遗传算法模拟出的LSS值为24.8 MPa,与实验结果误差仅为3%;随着保压时间的增加,超声焊接头强度呈现先快速增大后趋于稳定的变化趋势,当保压时间为5 s,时焊接界面处的熔融树脂基本固化完全,PEI树脂与碳纤维形成致密结构,焊接头强度达到稳定。Carbon fiber reinforced polymer composites(CFRP)are widely used in the aerospace field.The efficient bonding technology has an important effect on the manufacturing cost and safety of CFRP components.In this paper,carbon fiber reinforced polyetherimide resin matrix composites(CF/PEI)were welded by ultrasonic welding technology.The effects of ultrasonic welding pressure and welding time on the strength of ultrasonic welded joints were studied by single lap shear strength(LSS)test,and the micro morphology of section was characterized by scanning electron microscope.The experimental data were analyzed by linear fitting,and the time pressure parameters were optimized and the joint strength was predicted by combining BP neural network and genetic algorithm.Finally,the influence mechanism of holding time on joint strength was studied.The results show that when the welding time is 2.5 s and the welding pressure is 0.45 MPa,the maximum LSS is 25.6 MPa,and it is found that the higher welding strength is due to the formation of dense and stable structure on the joint surface.The experimental data are refined by BP neural network.The LSS value simulated by genetic algorithm is 24.8 MPa,and the error between the simulation and the experimental results is only 3%.With the increase of the holding time,the strength of ultrasonic welding joint increases rapidly first and then tends to be stable.When the holding time is 5 s,the molten resin at the welding interface is basically cured completely,and the PEI resin and carbon fiber form a dense structure,and the strength of ultrasonic welding joint is stable.

关 键 词：碳纤维复合材料 超声焊 焊接压力 单搭接剪切强度 保压时间 BP神经网络 

分 类 号：TB332[一般工业技术—材料科学与工程] TG44[金属学及工艺—焊接]