Research On Design And Manufacturing Of Flexible Circuit Board

Flexible electronics has become the mainstream trend in the future development of electronic equipment,and flexible circuits are a key component of the development of flexible electronic devices.Flexible circuits are light,thin,flexible,bendable,and even stretchable.They have good application prospects in the fields of flexible sensors,flexible displays,flexible wearables,and electronic skins.Therefore,it is of great significance to carry out flexible circuit design and manufacturing research.This paper presents the selection criteria and the range of process parameters for conductive materials and substrate materials suitable for wearable flexible circuits.Based on the pneumatic extrusion dual nozzle 3D printing technology,conductive silver paste/liquid silicone composite flexible circuits are fabricated.The specific research contents are as follows:To define the performance requirements of flexible conductive materials,use conductive silver paste as the conductive material for flexible circuits.By analyzing the influence of process parameters such as the inner diameter of the needle,printing pressure,printing speed and curing temperature on the molding effect and the conductive stability of the circuit,the best printing parameters are determined,that is,the 410 um needle is selected,the printing pressure range is 1.5 bar-2 bar,and the printing speed range 10 m/s-15 m/s,curing temperature is 60 ?.According to the selection criteria of flexible substrate materials,performance testing and analysis of common flexible substrate materials such as TPU and silicone were carried out,and finally liquid silicone was used as the substrate material of flexible circuits.Through the ABAQUS finite element software,the flexible circuit silica gel substrate was subjected to tensile deformation simulation analysis,and the tensile test simulation results of the silicone material were consistent with the actual test data.Combining the simulation data and the actual test results,the maximum deformation that the type 3 dumbbell-shaped silicone specimen can withstand is 56% of the initial length and the maximum stress is 2.5 MPa,which further confirms that the flexible circuit silicone substrate has good tensile mechanical properties.A new process for manufacturing flexible circuits based on pneumatic extrusion dual nozzle 3D printing is proposed.The flexible circuit is printed by analyzing the basic principles and forming process of the dual nozzle 3D printing flexible circuit.Through the test and analysis of the tensile and bending electrical properties of the flexible circuit,it is found that it still maintains good conductivity stability when the deformation is 33%,and the resistance remains unchanged after 300 bending experiments,thereby verifying The conductive silver paste/liquid silicone composite flexible circuit based on the dual-nozzle 3D printing technology has good electrical conductivity and mechanical properties under tension and bending.