Microwave Absorption of Structural Polymer Composites Containing Glass-Coated Amorphous Microwires

A new kind of glass fiber reinforced polymers (GFRP) incorporating ferromagnetic microwires are developed for microwave absorption applications. Strikingly, an orientation preference to the absorption due to the polarization effect of glass fibers is observed for the unidirectional GFRP laminates; there also exists a remarkable dependence of absorption on the number of laminates. These observations are rationalized by an equivalent circuit model. With wires addition, we established here the correlation of the microwave absorption performance with the local properties of wires such as wire geometry, the mesostructure including inter-wire spacing, wire orientation, wire pattern (random or continuous) and wire concentration. All these observed effects are elucidated within the framework of microwave absorption theory and equivalent circuit models.