陶瓷/FRP层叠复合构件的低频轴向振动套孔加工机理研究

During machining the lightweight-material laminate composite component consisting of engineering ceramics and fiber reinforced plastics(FRP), such machining defects as interlaminar delamination, fiber burr and ceramics crack are easily caused, which lead to poor machining quality, especially in drilling process. In this scientific research item, an applied background research on the low-frequency axial vibratory trepanning drilling of several typical ceramics/FRP laminate composite components, using the specially developed diamond trepanning drill, will be conducted intensively. The research content mainly involves: analyzing the kinematic and dynamic characteristics of low-frequency axial vibratory trepanning drilling, exploring the mechanisms of material removal and chip removal, and thus providing theoretical basis for the application of vibratory trepanning drilling process in machining laminate composite component; investigating the influence laws of machining conditions on technical effect parameters, such as drilling force, drilling temperature, precision and roughness, residual stress, and delamination, studying the evaluation method for the machined surface quality of laminate composite component and proposing an applicable comprehensive evaluation model, and accordingly giving guiding reference for the design, manufacture and use of laminate composite component. This project aims at revealing the machining mechanism and technical effects on low-frequency axial vibratory trepanning drilling of ceramics/FRP laminate composite component. The research results could provide effective reference information for the diamond trepanning tool in drilling laminate composite components with similar composing materials.

工程陶瓷和纤维增强树脂基复合材料（FRP）构成的轻质材料层叠复合构件加工中容易出现层间分层、纤维抽丝、陶瓷裂纹等缺陷，钻孔时尤其严重。本项目以典型的工程陶瓷/FRP层叠复合构件为研究对象，基于金刚石套料钻头对其低频轴向振动套孔加工技术进行基础性应用科学研究。具体内容包括：分析低频轴向振动套孔加工的运动学和动力学特性，研究低频轴向振动套孔加工的材料去除和排屑机理，为振动套孔工艺用于层叠复合构件的高质量制孔加工提供理论依据；研究钻削力、钻削温度、加工精度及粗糙度、残余应力、层间分层等工艺效果参数与加工条件之间的关系和影响规律，研究陶瓷/FRP层叠复合构件加工表面质量的评价方法并建立其综合评价数学模型，为该类型层叠复合构件的设计、制造和使用提供参考。本项目旨在揭示陶瓷/FRP层叠复合构件的低频轴向振动套孔加工机理及其工艺效果，为解决该类型复合构件的加工制造难题提供理论和技术参考。

工程陶瓷和纤维增强树脂基复合材料（FRP）构成的轻质材料层叠复合构件在装甲防护领域有着广泛应用。工程陶瓷和FRP皆为难加工材料，且材料性能和加工机理相差迥异，加工中容易出现层间分层、纤维抽丝、陶瓷裂纹等缺陷，钻孔时尤其严重，严重制约了其推广应用。本项目以轻型装甲防护领域应用最为广泛的氧化铝（Al2O3）、玻璃钢（GFRP）以及Al2O3/GFRP层叠复合构件为主要研究对象，基于新型薄壁金刚石套料钻头，理论和实验相结合对其低频轴向振动套孔加工技术进行基础性应用科学研究。分析了低频轴向振动套孔加工的运动学特性和变厚切削特性，揭示了该工艺在排屑、材料去除、轴向力等方面的优异特性，阐明了层叠复合构件的材料去除机理和缺陷形成机制，为振动套孔工艺用于层叠复合构件的高质量制孔加工提供理论依据；结合烧结/钎焊复合工艺，研制了新型薄壁金刚石套料钻头，实现了Al2O3/GFRP层叠复合构件的恒速进给孔加工，揭示了烧结和烧结/钎焊复合工艺金刚石钻头的磨损机理和失效机理，为钻头性能改进设计提供参考；阐明了常规加工与低频轴向振动加工条件下主轴转速、进给速度、振幅等工艺参数对轴向力、孔口质量、表面粗糙度、落料方式等工艺效果的影响规律，研究确定了孔口质量的评价手段和方法，为低频轴向振动套孔加工技术的工程应用提供工艺基础数据。研究结果表明，低频轴向振动加工能显著降低轴向力、改善孔加工质量、提高套孔加工的落料率，结合研制的新型薄壁金刚石套料钻头，能实现Al2O3/GFRP层叠复合构件的高质量恒速进给连续孔加工。本项目揭示了Al2O3/GFRP层叠复合构件的低频轴向振动套孔加工机理及其工艺效果，为解决该类型层叠复合构件的加工制造难题提供理论和技术支撑。本项目研究也是对单一难加工材料机械加工技术的完善和补充，将为新材料和新工艺的开发与应用提供理论指导和基础数据。