J. Phys. IV France 125 (2005) 487-489
DOI: 10.1051/jp4:2005125114

Experimental modeling of nonlinear photothermal effects in composite materials

G. Kalogiannakis¹, A. Moura^{2, 3}, J. Ravi², S. Longuemart², J.-S. Antoniow⁴, D. Van Hemelrijck¹ and C. Glorieux<sup>1, 5

1</sup>  Department of Mechanics of Materials and Constructions, Vrije Universiteit Brussel, 1050 Brussels, Belgium
²  Laboratorium voor Akoestiek en Thermische Fysica (ATF), Department of Physics and Astronomy, K.U. Leuven, 3001 Heverlee, Belgium
³  National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
⁴  Unité de Thermique et d'Analyse Physique, Laboratoire de Thermophysique, UFR Sciences, BP. 1039, 51687 Reims Cedex 2, France
⁵  Postdoctoral Researcher of Fonds voor Wetenschappelijk Onderzoek-Vlaanderen (FWO-V)

christ.glorieux@fys.kuleuven.ac.be

Abstract
An experimental model system was developed in order to investigate the nonlinear effects that originate from vibrating boundaries in photothermal techniques. It followed a primary investigation that demonstrated the effect of thermoelastic bending particularly studied in fiber reinforced composite laminates. The model consisted of such a laminate with a hole and a metallic piston piece that was made to fit exactly inside the hole. The piston position, and consequently the width of the air gap between laminate and piston, was periodically varied while collecting a IR radiometric photothermal signal. The nonlinear effect caused by the varying boundary condition experiment resulted in the generation of mixing frequency components in the photothermal signal.

© EDP Sciences 2005