PARAMETER DETERMINATION FOR THERMODYNAMICAL MODELS OF THE PSEUDOELASTIC BEHAVIOR OF SHAPE-MEMORY ALLOY BY RESISTIVITY MEASUREMENTS AND INFRARED THERMOGRAPHY

Two thermodynamical models of pseudoelastic behaviour of shape memory alloys have been formulated. The first corresponds to the ideal revers ible case. The second takes into account the hysteresis loop character istic of this shape memory alloys. Two totally independent techniques are used during a loading-unloading tensile test to determine the whol e set of model parameters, namely resistivity and infrared thermograph y measurements. In the ideal case, there is no difficulty in identifyi ng parameters. Infrared thermography measurements are well adapted for observing the phase transformation thermal effects.