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An original instrumented microindenter capable of testing materials up to 1000 C in an inert atmosphere has been developed. After describing the principle and its characteristics, the possibilities of the technique is illustrated with tests on NiAl(Pt) materials representative of the bondcoats of thermal barrier coatings. A modelling approach based on FEM calculations has been developed, which enables, by solving the inverse problem, to identify the variables of the constitutive law of the materials tested. Comparison of results thus obtained with published data when available shows a satisfactory agreement. This experimental technique, combined with the modelling approach, opens up a new way to determine the constitutive behaviour law of materials at a local scale and in a large temperature range.

We report on a wide-field optical monitoring method for revealing local delaminations in sandwich-type composite plates at video-rate by holographic vibrometry. Non-contact measurements of low frequency flexural waves is performed with time-averaged heterodyne holography. It enables narrowband imaging of local out-of-plane nanometric vibration amplitudes under sinusoidal excitation, and reveals delamination defects, which cause local resonances of flexural waves. The size of the defect can be estimated from the first resonance frequency of the flexural wave and the mechanical parameters of the observed layer of the composite plate

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