J. Phys. IV France
Volume 134, August 2006
EURODYMAT 2006 - 8th International Conference on Mechanical and Physical Behaviour of Materials under Dynamic Loading
Page(s) 739 - 744
Publié en ligne 26 juillet 2006
EURODYMAT 2006 - 8th International Conference on Mehanical and Physical Behaviour of Materials under Dynamic Loading
J. Cirne, R. Dormeval, et al.
J. Phys. IV France 134 (2006) 739-744

DOI: 10.1051/jp4:2006134114

Evolutions of the LASer Adhesion Test (LASAT) for the debonding of coatings on substrates above the millimeter range thickness

M. Arrigoni1, M. Boustie1, C. Bolis2, L. Berthe2, S. Barradas3 and M. Jeandin3

1  LCD (UPR 9028), ENSMA, 1 Av. Clément Ader, 86961 Futuroscope Cedex, France
2  LALP (UPR 1578), CTA, 16bis rue Prieur de la Côte d'Or, 94114 Arcueil Cedex, France
3  Centre des Matériaux/C2P-École des Mines de Paris, BP. 87, 91003 Evry Cedex, France

Published online: 26 July 2006

High power laser irradiation on a substrate coated on the opposite side drives a shock whose propagation and consecutive transmission/reflexion at the interface and free surfaces can yield to important traction inside the sample and particularly at the interface. For a given system, traction at the interface can be controlled by laser settings and therefore a LASer Adhesion Test of quality (LASAT) can be realised for many couples of substrate/coating system. The debonding is detected by VISAR measurements at the opposite face to the loading. However, due to the shortness of laser shock at the origin of traction, a strong decay of the initial shock occurs above a few hundredth microns in the substrate. Therefore, debonding cannot be obtained for most samples exceeding the millimeter range thickness.
Several solutions have been investigated for opening up the possibilities of the LASAT process for systems above the millimeter range. One solution would consist in generating the shock on the coating to produce traction at the interface independently of the reverberations of the substrate free surface. An analytical study of shock waves propagation into the coating/substrate system has been performed. It shows that traction can be produced at the interface only when the coating's shock impedance is much lower than that of the substrate. An experiment performed by high power laser shock of an al coating on a thick substrate evidences the debonding.

© EDP Sciences 2006