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Composite porous silica-DR1 films were obtained and have been analysed before and after poling by a static electric field. Spectroscopic ellipsometry was used to study the optical properties of layers of these composite material in the UV-IR spectral range (0.75-4.5 eV). Second harmonic generation was performed in the near-infrared spectral range. Preferential alignment of the dye molecules parallel to the pores perpendicular to the surface was shown by second harmonic generation experiments after the poling treatment. Increasing of the absorption and of the dichroïsm were also observed by spectroscopic ellipsometry analysis.

Due to their impressive capacity of sensing and actuating, piezoelectric materials have been widely merged in different industrial fields, especially aeronautic and aerospace area. However, in the aeronautic industry, the structures are operating under critical environmental loads such as high and very low temperature, which made the investigation of the effect of thermal forces on the piezoelectric structures indispensable to reach the high functionality and performance. The present paper focuses on the effect of thermal loads on the active vibration control (AVC) of structures like beams. For this purpose, a finite element model of composite beam with fully covered piezoelectric sensor and actuator based on the well-known high order shear deformation theory is proposed by taking into account the electrical potential field and a linear temperature field. Hamilton’s principle is used to formulate the electro-thermo-mechanical governing equations. The negative velocity feedback controller is implemented to provide the necessary gain for the actuator. Different analyses are effectuated to present the effect of the temperature ranging from -70°C to 70°C on the active vibration control of the composite beam.