Demonstrating a new ink material for aerosol printing conductive traces and custom strain gauges on flexible surfaces

Abstract

Aerosol Jet Printing is an emerging technology that holds much promise for the future of printable electronics and smart additive manufactured structures. Aerosol Jet Printers are capable of printing conformally on nearly any substrate due to their non-contact printing process and compatibility with a wide range of materials. These qualities allow these machines to be extremely versatile and capable of printing antennas, sensors, or even just conductive traces on PCBs and a wide variety of substrates. In this paper, a strain gauge sensor is designed and characterized using a new silver ink material from NovaCentrix and compared to a commercial off-the-shelf strain gauge. This work is the first to characterize the JS-A426 silver ink from NovaCentrix and demonstrate an application using an ultrasonic atomizer aerosol jet delivery system. After experimentally determining the conductivity of the silver ink, the length and area of the strain gauge were chosen to design a sensor with a theoretical resistance of 110 Ω. After aerosol printing and testing the printed strain gauge, it was found to have an average resistance of 116 Ω and a gauge factor of 1.85. These values are similar to commercial strain gauges and demonstrate that the aerosol printed strain gauge is a viable sensor that holds many advantages over traditional strain gauges: quick prototyping, conformally printed on any surface, elimination of any adhesive layer, and can be printed in less than a minute once the printer is setup.