Effects of thickness and texture on mechanical properties anisotropy of commercially pure titanium thin sheets

Simultaneous effects of thickness and texture on the anisotropy of mechanical properties and fracture behaviors of commercially pure titanium thin sheets were studied. The activation of different deformation systems, due to the split distribution of basal texture, led to mechanical properties anisotropy. The crack initiation and propagation energies, when the loading direction was parallel to the initial rolling direction, decreased with increasing thickness ranges from 0.25 to 1 mm. The changes of size, shape and distribution of dimples with increasing thickness confirmed the restriction of deformation systems and the development of triaxial stress state and plane-strain condition at the notch tip. However, in transverse-directed specimens, the energy release rate increased with increasing specimen thickness up to 0.75 mm and then decreased. The fractography of these specimens explained the simultaneous effects of thickness and texture on structural stability and high accommodated plastic deformation at the notch tip.

► Impact of texture on toughness strongly depended on thickness and loading direction.
► Fracture mechanisms were affected by metallurgical and geometrical constraints.
► The morphology of dimples was affected by the thickness and loading directions.
► Rational relations between fracture mechanisms and toughness values was observed.