One-shot measurement of thermal and kinematic fields from Infra-Red Image Correlation (IRIC)

¹ LMT Cachan, ENS Cachan/CNRS UMR 8535/Univ. Paris 6/PRES UniverSud Paris, 61 Avenue du Président Wilson, 94235 Cachan Cedex, France
² CEA Saclay, DEN-DANS/DMN/SRMA/LC2M, 91191 Gif sur Yvette Cedex, France

^a e-mail: anne.maynadier@lmt.ens-cachan.fr

Abstract

Many materials are concerned by strain localization, for instance PLC phe¨ nomena, Luders’ bands or Shape Memory Alloys (SMA). The experimental identification of such material behaviors requires the use of full field kinematic measurements, such as provided by Digital Image Correlation (DIC), as well as Infra-Red (IR) thermography to evaluate the associate thermal dissipation. Jointly, these field measurements allow for a full thermo-mechanical characterization of material behavior. However, the space and time association of both fields remains a major difficulty (antagonist surface texture requirements, imaging devices having different pixel number and acquisition rate...). In this paper, we introduce a much simpler experimental approach, which consists in a novel extended DIC technique applied to a single set of IR images. It gives access to both displacement and temperature fields decomposed over the same discretization. This technique, applied to tensile tests on a NiTi SMA, reveals both strain localization due to the phase transformation and associated thermal dissipation.