Study On Biomimetic Design And 3D Printing Preparation Of Continuous Carbon Fiber Reinforced Polylactic Acid Matrix Composites

Advanced structures and composite materials were listed as key research and development areas in the National Fourteenth Five-Year Plan,which maked them as an important direction for the current development of materials science.Compared with traditional metal materials,carbon fiber reinforced polylactic acid resin matrix composites have excellent properties such as high mechanical strength,high modulus,high temperature resistance and also had great biocompatibility.Consequnently,the carbon fiber reinforced polylactic acid resin matrix composites were widely used in aerospace,shipbuilding,vehicles,biomedical and national defense.However,with the development of application fields,the requirements for products were also continuously improved.As a result,the carbon fiber reinforced polylactic acid resin composites were faced the technical bottleneck of simultaneous improvement of various functions such as light weight,high strength and high toughness.In nature,the wing feathers of the eagle owl were arranged at different angles through the feather axis and the feather branches,which maked it have the characteristic of light weight and high strength.In this paper,the wing feather of the eagle owl was used as a biological model,and based on its microscopic arrangement structure,a bionic feather arrangement structure model was established to guide the structural design of continuous carbon fiber reinforced polylactic acid resin composites.Polylactic acid resin was used as the matrix material.Continuous carbon fiber was used as the reinforcement phase,and nano-scale silica particles was used as the additive.The continuous carbon fiber reinforced polylactic acid resin composites with the bionic feather structure was successfully manufactured throught the fused deposition 3D printer that was optimized and upgraded by the single extrusion inlet and single nozzle extrusion printing technology.Consenquently,the integrated molding of fiber-resin,and the high-precision controllable bionic variable-angle directional structure arrangement of carbon fiber was realized.The research on the design and preparation of biomimetic structural composites integrating structure-material-function was carried out,the effect of biomimetic feather directional arrangement on the mechanical properties of composites and the reinforcement mechanism was revealed,the 3D printing preparation of continuous carbon fiber biomimetic directional arrangement reinforced resin composite material was realized,and the bottleneck problem that composite materials were difficult to improve with various functions such as light weight,high strength and high toughness was solved.The main conclusions of this study are as follows:(1)The wing feathers of the eagle owl was choosed as the biological model.The structure design was based on the variable-angle arrangement of the feather shaft structure and the feather branch structure of the eagle owl wing.Simplify and extract the bionic feather arrangement structure model to realize the structural design of continuous carbon fiber reinforced resin composites.(2)Based on the single extrusion inlet and single nozzle extrusion technology to transform the fused deposition 3D printer.After the printing program and printing parameters was modified,and the cooperation between the printer's control system,motion system,feeding mechanism,printing nozzle was optimized.The integrated extrusion molding of continuous carbon fiber and polylactic acid resin was achieved.(3)The polylactic acid resin material was used as the matrix material,and the continuous carbon fiber was used as the reinforcing phase.Through the fused deposition 3D printer integrated with the fiber resin,the continuous carbon fiber reinforced polylactic acid resin composite with great mechanical properties had been successfully 3D printed.The influence of the continuous carbon fiber bionic structure on the mechanical properties and the enhancement mechanism was revealied,and the feasibility of the bionic structure design was verified.(4)3D printing biomimetic structure continuous carbon fiber reinforced silica/polylactic acid resin composite material and mechanical properties analysis.A series of silica particles reinforced polylactic acid resin composites were prepared,and1 wt.% of silica particles had the best reinforcement effect.The 1wt.% silica/polylactic acid resin was used as the matrix,3D printing biomimetic structure continuous carbon fiber reinforced silica/polylactic acid resin composites was printed,and the effect of biomimetic structure design on the mechanical strength of the composites was studied.