Coupling tomographic and thermographic measurements for in-situ thermo-mechanical tests

In order to determine the thermo-mechanical properties of a complex 3D woven ceramic composite material, an experiment at high and inhomogeneous temperature and its dedicated full-field measurement procedure is developed. 3D tomographic images of the tested sample are captured at different stages of loading in a synchrotron beamline, and an infrared camera captures a side view of the sample as it rotates in the x-ray beam. A pin-hole projective model of the thermographic camera allows one to map the thermal field measured under numerous orientations onto a 3D mesh of the sample built from an initial tomographic image or a model. The projective model has to be calibrated, and an original procedure is proposed thanks to an integrated digital image correlation algorithm based on the 'silhouette' of the sample (as only the protruding edges outlining the sample shape can be seen clearly). This procedure is illustrated with an experimental case study.

Automated summary

This paper presents an experimental method and full-field measurement procedure for determining the thermo-mechanical properties of complex 3D woven ceramic composite materials, capturing 3D tomographic images of the sample at different loading stages and mapping the thermal field onto a 3D mesh using a pin-hole projective model. An integrated digital image correlation algorithm is proposed to calibrate the projection model, with a focus on the silhouette of the sample shape. The procedure is illustrated with an experimental case study.