碳纤维增强树脂基复合材料制孔技术研究现状与展望

碳纤维增强树脂基复合材料(CFRP)具有优越的物理和力学性能,已在航空制造工业中得到大量应用。在主承力结构中,CFRP与金属材料的连接通常为机械连接。然而,CFRP的各向异性严重影响了其制孔质量。由于CFRP和金属具有截然不同的材料属性,CFRP/金属叠层结构制孔技术成为飞机装配过程中的一大难题。本文首先阐述了CFRP及其叠层结构在切削过程中的切屑形成机制、钻削力和钻削热的研究现状;其次,剖析了钻削过程中典型加工损伤,如毛刺与撕裂、分层缺陷及孔壁表面损伤的产生原因和影响因素;然后,介绍了CFRP制孔刀具材料和几何结构的优化设计研究进展,并综述了螺旋铣孔、变工艺参数钻削、"以磨代钻"和振动辅助制孔等多种CFRP及其叠层结构加工新技术及钻削过程的仿真研究。最后,借鉴钎焊工具和超声振动技术的独特优势,提出了磨粒有序排布钎焊金刚石工具的超声振动加工构想,以达到CFRP及其叠层结构的精密高效制孔加工这一目的。

Review and prospect of drilling technologies for carbon fiber reinforced polymer

Due to the superior physical and mechanical properties of carbon fiber reinforced polymer (CFRP), it has been widely applied in aviation industry. In primary load-carrying structures, the connection between CFRP and metal materials is mechanical joints usually. However, the drilling qualities are affected seriously by the anisotropy of CFRP. Drilling technology of CFRP/metal stacks has become a difficult problem in aircraft assembly process for the different properties of CFRP and metals. First, the chip formation mechanism, drilling force and drilling heat in drilling processes of CFRP and its stacks were explained. Second, the causes and influential factors of typical machining damage during drilling processes, such as burr and spalling, delamination defects and hole surface defects were analyzed. Then, the research status of optimization designs of materials and geometries of CFRP drilling tools were introduced. Various advanced process technologies of CFRP and its stacks, such as helical milling hole, varying parameter drilling, "grinding instead of drilling" and vibration assisted drilling, and simulation researches of drilling processes were reviewed. Finally, in order to realize the precise and efficient drilling processes of CFRP and its stacks, taking the unique advantages of brazed tools and ultrasonic vibration technologies, an ultrasonic vibration processing conception by brazed diamond tool with abrasive ordered arrangement was proposed.