Research On 3D Coaxial Printing Of Flexible Electronic Based On Liquid Metals

Flexible electronic is the circuit or electronic components manufactured by using some technology to make the base material or conductive material of traditional electronic be flexible.Flexible electronic has developed rapidly in recent years and has become the research focus for its advantages of good ductility,high adaptability,portability and so on.Gallium indium alloy,which is in liquid state at room temperature,non-toxic and have excellent flow performance and electrical conductivity,is the most widely used conductive functional materials in flexible electronic.However,the surface tension of gallium indium alloy is large and it is easy to aggregate into spheres,which makes its printing performance be poor.In this paper,a new method for the manufacturing of flexible electronic devices by 3D coaxial printing parts is proposed in which plastic base material can be printed through the coaxial print nozzle with liquid metals being wrapped up inside to form flexible conductor and flexible conductor can be printed into flexible electronic with the help of 3D printer.This method overcomes the problem of aggregating into spheres when gallium and indium alloy is directly printing.The main contents of this paper are as follows:1)Built a flexible electronic manufacturing platform based on 3D co-printing manufacturing method.The motion module,extrusion module,coaxial print head and work table were designed reasonably according to process requirements and open firmware was revised to adapt to print requirements.2)Study on the printing process performance of liquid metals.Impact of wettability between liquid metals and plastic base materials,surface micromorphology of plastic base materials and materials extrusion speed on printing effect was studied respectively.Material selection criteria and process parameters selection range were given according to the experimental results.3)A flexible inductance sensor was first made.The advantages of the sensor were analyzed and printing processes were introduced.This paper derived the detection models of the sensor in the processes of different physical deformation situations and built comprehensive static performance evaluation system,developed integrated data acquisition and analysis software to test the static performance of the sensor systematically.4)The applications of the flexible sensor in position detection were demonstrated,and the applications of 3D coaxial printing manufacturing method in other fields were explored.These experiments demonstrated the application potential of this method in the fields of bio-medical,wearable devices and other parts.