Work-hardening stages and deformation mechanisms during tensile tests of commercially pure titanium containing α′-martensite

High purity titanium usually requires thicker plates because of its limited mechanical strength on account of the low impurity content. Heterogeneous microstructures can be considered an alternative to enhance the material’s ductility and strength. This work incorporates precipitation of α′-phase trough partial recrystallization as an approach to achieving high strength-ductility in commercially pure Ti. Cold rolling and annealing were able to enhance mechanical properties and produced recovered and recrystallized constituents with different mechanisms of deformation. Tensile tests identified three work-hardening stages. Ti CP deformed plastically without significant mechanical twinning. Annealing at 400–500 °C achieved the most noteworthy increase in mechanical strength, achieving up to 600 MPa with a total elongation of 23%. Dislocations glide dominated the deformation process. Recrystallization resulted in grain growth, mostly to annealing temperatures of 700 to 900 °C, and in the increase of tensile strength, also enhanced by high volume fraction of α′-martensite.Graphical abstract