Applications of Co-rich Amorphous Glass-coated Microwires for Monitoring the Matrix Polymerization

A remarkable magnetic softness and giant magnetoimpedance (GMI) effect have been observed in Co-rich glass-coated microwires. Insulating and flexible glass-coating allows use of such glass-coated microwires for stresses or temperature monitoring in smart composites using free space facility. Such composites with magnetic microwire inclusions can present tunable magnetic permittivity. We report on in-situ evolution of the transmission and reflection parameters during the polymerization of the polymer containing magnetic microwire inclusions. A remarkable change of the reflection and transmission in the range of 4-7 GHz upon the matrix polymerization is observed. Observed dependencies are discussed in terms of the effect of the temperature and stresses variation on magnetic properties of glass-coated microwires during the thermoset matrix polymerization. The results obtained are considered as the basis of a new sensing technique that allows non-destructive and wireless monitoring of composites with ferromagnetic glass-coated microwire inclusions with magnetic properties sensitive to tensile stresses and temperature.