Research On Inkjet 3D Printing Of Graphene Composites

Inkjet 3D printing technology is a new type of non-contact fabrication technology,which can be used to print complex 3D structures.Due to its low cost and fast printing advantages,the technology will enable small batch printing and customized fabrication,which is of great significance for improving efficiency and cost saving.As the first two-dimensional material in the world,graphene can be used as an ideal reinforcement additive in composite with other materials.Graphehe additive can improve the performance of composite materials due to its unique two-dimensional structure,excellent mechanical and electrical properties.Based on the above advantages,it is expected that graphene composite materials with strong designability and controllable structure can be obtained by thermal-bubble inkjet 3D printing technology.Such technology will promote the development of graphene composite materials for functional and intelligent applications,and further expand the practical application of 3D printing.The content of this research includes the following three parts:(1)Highly dense alumina ceramic substrates were fabricated by rapid prototyping technique using thermal bubble 3D printing technology.The effects of different sintering temperatures on the phase structure,physical properties,and mechanical properties of 3D printed ceramics were systematically studied.Meanwhile,the principle of improving the density of 3D printed ceramics was studied.The results show that the 3D printed ?-Al2O3 ceramic sintered at 1600? for 2 h has achieved maximum density of 95.2%,volume shrinkage rate of 32%,Vickers hardness of 291.6 Hv,surface roughness of 3.7 ?m,and maximum compression strength and flexural strength of 89 MPa and 49.4 MPa,respectively.The 3D printed ceramics have good physical and mechanical properties.Through this research,a feasible approach of low cost,rapid fabrication,energy saving and environmental friendly has been developed to produce highly dense ceramics with complex structures.(2)Graphene circuits-on-ceramics were fabricated by rapid prototyping technique using thermal-bubble inkjet 3D printing technology.The effect of the printing process on the morphology and conductivity of graphene circuits-on-ceramics was studied.The feasibility of manufacturing graphene/alumina ceramic circuit board via this technique was demonstrated.The results show that the 3D printed graphene circuits-on-ceramics has achieved conductivity of 5·34×102 S·m-1 after annealing at 600? in nitrogen atmosphere The average adhesion of reduced graphene oxide(rGO)to 3D printed ?-Al2O3 ceramic is 7.5 N/m.the 3D printed graphene circuits-on-ceramics has good electrical conductivity,mechanical properties and chemical stability.This research explored new direction for the application of graphene materials in the field of ceramic circuit board.(3)The graphene oxide/polyacrylamide/sodium alginate composite hydrogels were prepared by chemical crosslinking.The phase structure,physical properties and mechanical properties of the composite hydrogels were studied.The composite hydrogel can be stretched to 27 times its original length without breaking,and its maximum tensile strength is 245 kPa.Meanwhile,the composite hydrogel has achieved compressive strength of 45.1 kPa when the compression ratio is 70%.The results show that the composite hydrogel has excellent mechanical properties.In addition,a novel and simple pattern printing method is developed.High-resolution patterns can be quickly printed on the surface of high-strength composite hydrogels using thermal-bubble inkjet 3D printing technology.The patterned composite hydrogels can deform from two-dimensional plates into three-dimensional shapes when subjected to external stimulations.This allows deigning and realization of complex and controllable 4D objects of the composite hydrogels.