Numerical study of mean-field approach capabilities for shape memory alloys matrix composites descriptionY. Chemisky1, B. Piotrowski2, T. Ben Zineb2 and E. Patoor1
1 LPMM, Metz University, Arts et Metiers ParisTech, CNRS, Ile du Saulcy 57045 Metz, France
2 LEMTA , Nancy University, CNRS, 2 rue Jean Lamour, 54500 Vandoeuvre-les-Nancy, France
Published online: 1 September 2009
With the development of SMA devices, new alloys are developed to enhance some specific properties like temperature hysteresis, plastic yield limit, change of transformation temperatures... Phase precipitation or inclusions addition are often use for these purposes. To predict the behavior of these heterogeneous materials and allow structures simulations, mean-field approaches like MoriTanaka homogenization scheme are convenient. But for phase-transformation strain mechanism, localization of deformation and, in a second step, saturation of transformation strain around inclusions have a significant impact on the global behavior. To check the capability of Mori-Tanaka scheme to predict the behavior of these heterogenous functional materials, a unit cell finite element analysis is considered as reference solution. One inclusion is embedded in the matrix, with respect to the fraction volume of both phases. Two situations are performed, both for NiTi-based materials. First represents the precipitation effect of Ni-rich elastic precipitates Ni4Ti3 for annealed Ni-rich materials. Second case considers elastoplastic Nb inclusions in a NiTi matrix, which induce a wide variation of reverse transformation temperatures. Limits of the homogenization approach chosen are studied in these two cases.
© Owned by the authors, published by EDP Sciences 2009