Mechanical–electromagnetic coupling of microwire polymer composites at microwave frequencies

We have fabricated a set of microwire composites with varying wire concentrations and studied their effective complex permittivity under the tensile stress at a frequency range of 1–6 GHz. It has been found that with increasing wire concentration the composite presents increasing effective permittivity and strain sensitivity. The Gaussian molecular network model shows a complex strain dependence of sensitivity due to the composite architecture influenced by the wire concentrations. All these results indicate the proposed composite are excellent candidate materials for the microwave sensing and structural interrogation applications.