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A single phase hexagonal close packed Zircaloy 2 was cold deformed to different reductions by laboratory rolling. Systematic characterisations of the structural developments were carried out. Bulk texture developments were gradual, strongest developments being noticed at the highest strain. Although formation of well defined deformation fibre(s) could not be identified, overall developments in deformation texture were best captured through Taylor type models incorporating only prismatic slip. Strain localisations were observed as single or double walled dislocation structures at approximately 45 and 60u to the rolling direction. Such strain localisations were always associated with significant lattice reorientations or misorientation developments. Relative softening in lattice strain, observed at the higher reductions, can possibly be explained by the appearance of extensive strain localisations and the associated concurrent local dynamic recovery. The grains or orientations with dominant presence of strain localisations could be indirectly related to negative textural softening.

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Zircaloy 2, a cast and hot forged alloy with a Widmanstätten structure, was warm/hot rolled to 40 and 80% reductions at approximate working temperatures of 200, 400, 600 and 800°C. The bulk crystallographic texture had clearly different patterns of developments between 200/400 and 600/800°C deformed structures. The estimated lattice strain, on the other hand, had shown noticeable relative softening and hardening after the respective deformation temperatures of 600 and 800°C. The patterns of macroscopic developments, both in bulk crystallographic texture and in lattice strain, could be explained from the microstructural observations. The difference in bulk crystallographic texture was primarily related to the preferred appearance of recrystallised grains. The 600°C rolled structure was associated with recovery/recrystallisation and a concurrent softening while the effects of a similar softening was suppressed through significant intermetallic precipitations and associated strain localisations in the 800°C rolled material.

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