ROZINA STEIGMANN, ADRIANA SAVIN, NICOLETA IFTIMIE NONDESTRUCTIVE EVALUATION OF METALLIC FILLERS EMBEDDED IN POLYESTER MATRIX Composites made from metallic fillers embedded in polymer matrix have good shielding properties as electrical point of view and tribology properties from mechanical point of view. These properties depend on amounts, shapes, sizes, and combinations of fillers and matrix. This paper proposes an electromagnetic method for determination of metallic fillers concentration in composite materials from metallic fillers embedded in polyester matrix. The bulk resistivity and dielectric permittivity were measured but these measurements are less influenced by the fillers concentration. The amplitude measurement of e.m.f induced in the reception coil of the focalized electromagnetic transducer and their averaging for the scanning of a relative large zone of the composite has proven to be an efficient method. The average amplitude linearly decreases with the increasing of fillers concentration, and has different values for Cu and AISI 316 fillers.
Keywords: Polyester, metallic fillers, composite, electromagnetic evaluation, S parameters