Study of the α/β phase transformation of Zy-4 in presence of applied stresses at heating: analysis of the inherited microstructures and textures

The α→β→α phase transformation of Zy-4, as well as the inherited microstructures and textures have been investigated, in presence (or not) of applied tensile stress during the anisothermal α→β transformation. Without applied stress, the β treatment led to an inherited α texture sharper than the initial one. A detailed analysis of this texture change revealed a strong variant selection in the β→α transformation. With applied stress, transformation plasticity as well as creep of the β phase were clearly identified on the dilatometric curves. Moreover, the sharpness of the inherited α texture was significantly reduced. This has been related to a strong reduction of variant selection in the β→α transformation.