Monitoring the Effect of Relative Humidity during Curing on Dielectric Properties of Composites at Microwave Frequencies
نویسندگان
چکیده
The electromagnetic parameters of a composite material can depend on the environment in which the material is cured. Nondestructive monitoring of composite materials during curing offers a means of assessing whether or not the final product will function as specified. Microwave measurements of complex permittivity and permeability have been made on a polyurea/polyurethane hybrid containing ferromagnetic filler particles. It was observed that the permittivity of the samples is strongly affected by environmental relative humidity whereas the effect on the permeability is less significant.
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