基于表面微织构的钛合金与CFRP激光连接研究  

Laser Joining of Carbon Fiber Reinforced Plastics to Titanium Alloy via Laser Texturing

作　　者：刘一凡 周宝升 张涛 牛得田 王世嘉 苏健晖 宋晓国[1,2] 檀财旺 Liu Yifan;Zhou Baosheng;Zhang Tao;Niu Detian;Wang Shijia;Su Jianhui;Song Xiaoguo;Tan Caiwang(State Key Laborutory of Adeonced Welding and Joining,Harbin Inastitute of Technology,Harbin 150001,Heilongjiang,China;Shandong Proeincial Key Laborutory of Special Welding Technology,Harbin Instite of Technology at Weihai,Weihai 264209,Shandong,China;Natioval Invitation Center of High,Speed Train at Qingdao,Qigdao 266108,Shaudong,China)

机构地区：[1]哈尔滨工业大学先进焊接与连接国家重点实验室,黑龙江哈尔滨150001 [2]哈尔滨工业大学(威海)山东特种焊接技术重点实验室,山东威海264209 [3]国家高速列车青岛技术创新中心,山东青岛266108

出　　处：《中国激光》2022年第18期30-40,共11页Chinese Journal of Lasers

基　　金：国家自然科学基金(52074097);山东省优秀青年基金(ZR2021YQ30);国家高速列车技术创新中心研发计划(CXKY-02-02(2020))。

摘　　要：钛合金与碳纤维增强树脂基复合材料(CFRP)的异质复合接头在航空航天和交通等领域具有广阔的应用前景。激光连接钛合金与CFRP具有效率高的优点,但整体连接强度较低。本文开展了表面变宽度网格微织构TC4与CFRP激光连接工艺以及连接界面强化机理的研究,研究结果显示:随着微织构宽度增大,CFRP在TC4表面的接触情况由不润湿变成润湿,当微织构宽度为0.2 mm时,接触角最小,为49.91°,此时的润湿性最好;表面微织构显著提高TC4表面对熔化CFRP的吸附能力,促进了界面的机械嵌合作用;接头的拉剪力最高可达2596 N,较未处理接头提高了约154%;接头的断裂形式除了界面断裂及内聚断裂外,还存在TC4表面氧化物的剥离,佐证了TC4与CFRP界面结合强度的提升;界面上还生成了新的化学键合。微织构能增加界面接触面积并实现表面改性,促进CFRP与TC4在高温下发生化学连接,从而进一步提高接头强度。Objective Lightweight structure has become a focus in industrial fields.One of the research hotspots is the effective joining of dissimilar materials.Because of their high specific strength,titanium alloys have been widely used in aerospace and automotive engineering applications.Carbon fiber reinforced plastics(CFRP)have many advantages over traditional metals,such as higher specific strength,fatigue resistance,and corrosion resistance,and have a broad application prospect to further realize lightweight.The laser joining of titanium alloy and CFRP can combine the advantages of the two materials and broaden their application.However,because of the large differences in microstructure and physical properties between the two base materials,the joining strength is relatively low.The properties enhancement of metal/CFRP joint can be achieved by improving mechanical interlocking and chemical bonding.The laser texturing process can fabricate a microstructure to improve the surface roughness of metal,as well as change the chemical state of the metal surface.Thus,the laser joining process of TC4 to CFRP via laser texturing TC4 surface and the strengthening mechanism of the interface were studied by us.Methods Ti-6Al-4V alloy(TC4)and polyether ether ketone reinforced by 30%carbon fibers(CFRP)were selected as base materials.The resin matrix of the composite material was polyether ether ketone(PEEK).The TC4 sheets were treated by laser texturing before laser joining.To obtain ideal micron-scale grooves,the spacing between each grid was 1 mm,and each grid line was filled with multiple equidistant scan lines.The number of scan lines was adjusted to control different micro-texture widths,and the micro-texture width in this study were set to 0.1-0.5 mm,as shown in Fig.1.To evaluate the mechanical properties,tensile shear tests with a stretch speed of 0.5 mm/s were used.A high-temperature wetting angle measurement system was used to characterize the wettability of melted PEEK under different TC4 surface states.The optical digital

关 键 词：激光技术 激光连接 微织构 润湿性 机械嵌合 化学连接 

分 类 号：TG456.7[金属学及工艺—焊接]