Study of Thermomechanical Behavior of Refractory Materials Under Thermal Gradient. Part I – Presentation of ATHORNA Device and Experimental Protocol

Background: Improving the understanding of how a refractory material responds to thermal shocks and allowing the validation of finite element models require a valuable tool for experimental data collection. Objective: This paper introduces an innovative, sophisticated, and highly reliable experimental device designed to apply a controlled cyclic thermal gradient in a disk-shaped ceramic refractory sample and to simultaneously monitor thermome-chanical response and potential damage. Methods: This device, named Advanced measurements for in-situ Thermomechanical monitORing of large sample uNder thermal grAdient, is based on a CO2 laser beam to generate a calibrated thermal flux sequence at the top face while accu-rately measuring temperature field at the bottom face by an infrared camera. The displacement field of the bottom face is also continuously monitored by a stereo-vision system, enabling a precise measurement of 3D displacements and, thus, of the local strains. An accurate monitoring of the crack extension is performed thanks to the Two-Part Digital Image Correla-tion technique. Results: Throughout the thermal cycling sequence applied to an exemplar sample, the device has proved to be a robust and reliable system able to provide very accurate experiment data in terms of displacement, strain, temperature fields and crack length/opening. Conclusions: This device represents a significant advancement in in-situ monitoring of a refractory sample and contributes to the comprehensive characterization of materials under thermal gradients. More investigations and comparison with ther-momechanical Finite Element modelling are shown in a second part of this paper.