System and method for measuring the interface tensile strength of planar interfaces

摘要

A system for measuring the tensile strength of a planar interface between a substrate and a coating which includes an energy source that generates an electromagnetic beam along a first axis, and a sample assembly disposed along the first axis having a first face, and a second face, where the first and second faces are oppositely opposed. The sample assembly includes a confining plate, an energy absorbing layer, a substrate and a coating having a free surface, all in intimate facing contact with each other, and where the sample and coating are in intimate facing contact forms a substrate/coating interface. The coating is positioned along the first axis so that the coating free surface forms the sample assembly second face and the confining plate forms the sample assembly first face. The sample assembly further includes a pulse element for generating a stress pulse responsive to the electromagnetic beam. The substrate and the coating are arranged to receive the generated stress pulse such that the coating free surface moves in response to the stress pulse propagating therethrough. The system further includes a measuring element for measuring the movement of the coating free surface in response to the generated stress pulse, and a calculation element coupled to the measuring element for determining the tensile strength at the substrate/coating interface from the measured movement of the coating free surface. The measuring element is a laser Doppler displacement interferometer.