Foil-based strain gauges with nanogranular platinum structures for the integration in elastomer gaskets

摘要

This paper presents the design, fabrication and characterization of foil-based strain gauges using nanogranular Platinum (ng-Pt) as strain sensing material. The strain gauges are later to be integrated into elastomer gaskets to allow condition monitoring. In this work, Focused Ion Beam Induced Deposition (FIBID) is used for the formation of ng-Pt structures. Using this technology, ng-Pt structures can be deposited in any shape and on almost all surfaces. Due to the very small dimensions of the sensing elements, the overall size of the strain gauges can also be very small and is only limited by the possibilities to handle them. Thus, it is not only possible to integrate the strain gauges into elastomer gaskets causing minimum damage in the host material matrix, but also to measure strain locally on very small areas. Additionally, the formation of a Wheatstone Bridge circuit on the strain gauge is possible without enlarging the strain gauges dimensions dramatically. This enhances the strain sensitivity even further and compensates temperature dependency. A full bridge strain gauge with dimensions below 20 μm is feasible.