MODELING THE MECHANICAL RESPONSE OF ROLLED ZIRCALOY-2

An elastoplastic self-consistent model has been implemented to perform a systematic study of the response of rolled Zircaloy-2 subjected to mechanical loading. The intergranular stresses induced by cooling the material from 898 K to room temperature are calculated, accounting for the experimental texture, and compared with experimental data. The elastoplastic response in tension and compression along the rolling and the transverse directions of the sheet is predicted and compared against the results of uniaxial tensile and compressive tests performed in the same material. The role of the internal stresses on the yield stress and the elastoplastic transition is analyzed, and information about the active deformation systems in the individual grains is inferred from the comparison. Indirect inference of the parameters describing the deformation mechanisms is the only available means, because it is not possible to grow single crystals of these alloys. The results of this study demonstrate the adequacy of self-consistent schemes for predicting intergranular stresses and the significance of the latter on the mechanical behavior of the material.