<p>A number of additively printed electronics technologies have emerged including aerosol-jet printing, ink-jet printing, dispense-on-demand printing, screen-printing, gravure printing, and flexography.&nbsp; The use of additive manufacturing allows the design freedom to integrate sensors and electronics on non-planar curved surfaces ever closer to the desired point of measurement than possible through the use of commercial off-the-shelf sensors.&nbsp; In addition, significant reduction in the costs related to working capital for inventory, inventory-management and logistics support activities can be realized through the use of additive technologies.&nbsp; Electronics AM provides the potential of printing sensor and electronics on demand without the need for tying up working capital in inventory, or incurring costs related to climate-control storage.&nbsp; The minimum lot-size of the manufactured part can be as low as required for the current-need.&nbsp; For long-life systems, the use of electronics AM allows for designing out part obsolescence for some classes of parts without any need for lifetime buyouts.&nbsp; Electronics AM is finding application in a number of applications including healthcare, wearable, military, and even consumer electronics.&nbsp; In this paper, a process study was performed on the FR4 board while taking into account multiple printing parameters for the direct-write system. The process parameters include ink pressure, print speed, and stand-off height, as well as their effect on the trace profile and print consistency using white light interferometry analysis. The printed traces have also been studied for different sintering conditions while keeping the FR4 board's temperature limit in mind. The paper also discusses the effect of sintering conditions on mechanical and electrical properties, specifically shear load to failure and resistivity. The data from this was then used to print strain gauges and compared them to commercially available strain gauges. By reporting the gauge factor, the printed strain gauge has been standardized. The conductive ink's strain sensing capabilities will be studied under tensile cyclic loading (3-point bending) at various strain rates and maximum strains. Long-term performance testing will be carried out using cyclic tensile loads.</p>

Repeatability and Extended Time Stability Study of an Additively Printed Strain Gauge Under Different Load Conditions

Paper Proceedings: https://asmedigitalcollection.asme.org/InterPACK/InterPACK2021/volume/85505

ASME 2021 International Electronic Packaging Technical Conference and Exhibition (InterPACK2021)

Supporting the need among researchers worldwide for additional online and multimedia content, ASME now offers the ASME Conference Video Collection. This platform will collect and provide long-term access to conference presentation videos, encompassing all technology areas within ASME's technical conference and events program. About 30,000-40,000 engineers across all mechanical engineering and related disciplines participate in ASME conferences each year. This includes authors of approximately 6,000 to 8,000 technical papers published by ASME, the majority of whom also submit video presentations for our virtual conferences. The video collection will be available as an add-on to existing product packages or as a separate subscription.