PZT volume fraction’s impact on electrical and thermal characterization of the piezoelectric composite PU/PZT
Résumé
Lead zirconate titanate (PZT) is a well-known ceramic for his mechanical-electrical conversion since he has the larger piezoelectric coefficients. It is also known as a pyroelectric material. Nonetheless, this piezoelectric material is rigid and firm and cannot be used in flexible applications. The polyurethane (PU) which is an electrostrictive polymer known as a low electromechanical converter is the base matrix that can be loaded by the PZT as composite. This mixture was made to combine between the flexibility of PU and the larger piezoelectric coefficient of PZT. These studies involved its dielectric and mechanical characterization, but its thermal characterization is rarely found. This work proposes to elaborate PU with different fraction of PZT, to investigate the electrical and the thermal characterization of this composite, and to figure out the impact of PZT volume fraction on its thermal parameters. The electrical characterization involves the dielectric constant and the electrical conductivity of each sample. While the thermal characterization focuses on measuring the thermal conductivity using both, an indirect and a direct measurement technique. The indirect one uses Flash method to figure out thermal diffusivity and DSC to measure the specific heat capacity. As for the direct method, it consists on placing the sample between two heat sources where the heat flux is imposed and the temperatures are measured.