Élaboration et validation expérimentale de modèles prédictifs du comportement diélectrique des composites à base de titanate multi-phases en hyperfréquence

Abstract

The objective of this work is to study the ternary composites dielectric behavior, in the microwave domain, and to simplify the ternary models into binary ones using time domain spectroscopy. We developed different needed samples using epoxy resin (Re), manganese dioxide (MnO ) and one of three different titanates (XT): barium titanate (BT), calcium titanate (CT) or magnesium titanate (MT). These samples dielectric behavior is inspected over a wide frequency band extending from DC to 5 GHz. This aims to optimize the predictive model based on the modified Lichtenecker law (MLL) through a better smoothing of the shape factor making the theoretical and experimental results very close to each other. The comparison between these results shows that the modified Lichtenecker model is pertinent for ternary mixtures (Re-XT-MnO ) with an appreciable accuracy degree. Another numerical approach has been applied to the Re-[Re-XT-MnO ] mixtures using a binary mixture model equivalent to the previous of the ternary and based on a simplified MLL expression and preserving the same constituents. This model results are in good agreement not only with the ternaries being modeled with this same law but also with other mixing laws appreciated with binary composites.