Low-cost Fabrication of High-precision Conformal Films Based on Pneumatic/Electrical/Thermal Synergistically Driven Jetting Micro-3D Printing

doi:10.3901/JME.260087

Abstract

Abstract: High-precision curved conformal films/coatings are an important part of 3D curved conformal electronics, structural health monitoring, intelligent skins, conformal sensors and other products, which have extensive applications in aerospace, national defense and military industries, and intelligent electronics field. However, the efficient, low-cost, normal temperature/pressure manufacturing of high-precision conformal films is a major problem in current research. A new method for manufacturing high-precision conformal films is proposed by three-axis linked pneumatic/electricity/heat synergistically driven jetting micro-3D printing: through the pneumatic pressure to drive material into the nozzle, piezoelectric impact needle synergistic nozzle heating to achieve stable jetting of high viscosity material microdroplets, substrate heating regulates the deposition and curing behavior of microdroplets on curved surfaces, and ultimately realizes the preparation of high-precision conformal films using high-viscosity materials; Taking the industrially widespread polyimide (PI) material as a case study, we investigated the rheological behavior and viscosity characteristics of the material suitable for printing via the proposed method; Through experiments, the influences of key process parameters on stability of conformal film preparation, thickness uniformity, and surface quality are revealed;Combined with the optimized process parameters, high-precision PI conformal films with an average thickness of 22 μm and thickness deviation <2 μm were successfully fabricated on semi-cylindrical glass substrates, This method is suitable for materials with different viscosities (such as PI, zirconia ceramics, PDMS, etc.), and can fabricate high-precision conformal films on various substrate materials (glass, resin, metal, etc.) and on multiple complex curved substrate surfaces (e.g., spherical surfaces, stepped surfaces, wavy surfaces, etc.), exhibiting good universality. The prepared curved-film heater achieves a maximum temperature of 144.3 ℃ at 14 V, with a temperature deviation of <2% in the heating area, showing a highly uniform heating effect. This proposed method provides a new solution with industrialized application prospects for efficient and low-cost fabrication of high-precision conformal films/coatings under normal temperature and pressure conditions.

Key words: pneumatic/electrical/thermal synergistically driven jetting micro-3D printing, conformal films, microdroplet, in-situ curing, high-viscosity material jetting

CLC Number:

TB383

WANG Yongqiang, ZHANG Houchao, HUANG Junjie, LI Hongke, ZHU Xiaoyang, YANG Jianjun, LAN Hongbo. Low-cost Fabrication of High-precision Conformal Films Based on Pneumatic/Electrical/Thermal Synergistically Driven Jetting Micro-3D Printing[J]. Journal of Mechanical Engineering, 2026, 62(3): 298-310.

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