Report on a simultaneous ion viscosity, strain and impedance measurementtechnique using a novel integrated dielectric, optical fiber andpiezoelectric sensing element for the online characterization of smartstructures

摘要

This paper reports on a simultaneous ion viscosity, strain and impedance(SISI) system in order to measure the physical and chemical properties ofcomposites during their curing process. The SISI system uses an integratedmulti-sensing element, entitled DOP, that is comprised of dielectric (D), opticalfiber (O) and piezoelectric (P) sensors. This system was used to measureseveral data simultaneously in real time andinsitu. The resultsclearly show that there is a direct relationship between the ion viscosity,impedance and strain changes during the curing process. It was found thatdielectric sensor is very sensitive to physical and chemical changes of thecomposite both in the heating and cross-linking periods. The piezoelectricproved to be a useful element during the heating period with a very sensitiveand surprising behavior during the cooling period. The optical fiber alsodemonstrated a very striking profile in strain variations duringcooling.