Research On The Development And Application Of Desktop Level Circuit Structure 3D Printer

With people’s attention to environmental protection and the increasing demand for electronic products,3D printed circuit has become an important topic in additive manufacturing field in recent years.Using 3D printing technology to realize rapid prototyping of circuit structure is not only enable the green manufacturing,but also can solve the technical problems such as antenna miniaturization and embedded packaging of electronic products.Multi-material3D printing means that the printer can print modules with different properties of materials in the same printing task.This technology can realize the synchronous printing and molding of circuits and substrate boards,thus simplifying the circuit manufacturing process.In this study,a technology scheme combining melt deposition forming and direct writing printing is proposed and applied in the field of circuit forming.A dual-nozzle 3D printer integrating these two technologies is built,and the specific design process of the printer is described in details.Several RFID antennas and a semiconductor radiator used for heat dissipation of tablet computer are printed using polylactic acid（PLA）and normal temperature quick-drying conductive silver paste respectively.Through these two sets of printing cases,the process details of model modeling,slice setting and electronic module embedding in the process of multi-material 3D printing circuit are discussed in detail.It provides an effective reference for the subsequent equipment improvement and process route optimization.The specific research contents of each chapter are as follows:Firstly,the classification and development of 3D printing technology are introduced,melt deposition and direct writing are described in detail.The characteristics and applications of multi-material 3D printing technology are discussed,and the potential technical advantages and research status of this technology in RF antenna and electronic product manufacturing are emphatically introduced.One of the main research contents of this paper is to build a dual-nozzle 3D printer which combines melt deposition and direct writing.The main frame of the printer is Prusa i3（gantry type）structure,with a printable area of 220 mm×190 mm and running Klipper firmware program.In order to reduce the weight of the printer head,sherpa mini short-range extruder and E3DV6 heating head are selected to form the melt deposition printing head.A direct writing extruder based on the linear guide sliding table is designed,which greatly reduced the X-axis space occupied by two printing heads while realizing the lightweight of the head,and improved the available area of the printing platform.Subsequently,the modeling process and slice setting of the multi-material printing model are given.Through the printing test of several models,the molding accuracy of the printer is investigated,and the feasibility of the 3D printing circuit process is verified.Based on the design of dual-nozzle 3D printer,two kinds of RF antenna models with different structures are selected as experimental analysis objects.After analyzing the influence of substrate thickness and antenna arm length on antenna performance using Ansys HFSS software,four RF antennas of different sizes were selected for printing,and S₁₁ curve measurement was carried out on the printed parts with vector network analyzer.The results showed that the resonant frequencies of the four antennas all shifted to the low frequency direction by about 185MHz.According to the printing accuracy and material system,the antenna model size was further adjusted and the printing test was carried out.The improved RF antenna printing part met the design requirements of resonant frequency of 915 MHz and bandwidth of more than 150 MHz under-10 d B.A radiator embedded in a circuit is printed by a designed printer.Through this case,the modeling ideas and related matters for attention when printing electronic products are given in detail,and the feasibility of using conductive silver paste as a wire to connect circuit modules is verified.According to the observation and measurement,the integrated printed radiator can reduce the CPU temperature of tablet computer from 52℃to 37℃in 80 seconds under the condition of high load use,which displays a good heat dissipation effect.Finally,the work content and experimental results of this paper are summarized,and the improvement ideas of the equipment construction in this research institute are given,as well as the future development prospects of multi-material 3D printing electronic products technology are prospected.