Correlation between substructure and mechanical properties of α-Ti at varying deformation temperatures 4.2–373 K

The correlation between the substructure of α-Ti predeformed at temperature T1 and its mechanical properties (stress of onset of plastic deformation, true rupture strength, relative elongation on subsequent deformation at the temperature T2 varying from 4.2 to 373 K have been studied. It is shown that the changes in the mechanical properties at T1>T2 and T1<T2 are fundamentally different. In contrast to the isothermal deformation at T2, in the T1>T2 case the increment in the flow stress is smaller and the total plastic strain does not exceed the highest isothermal value; conversely, at T1<T2 the yield stress and the total ductility surpass the isothermal level. The different predeformation effects are connected with the stability of the developed substructure against subsequent deformation: it is low if T1>T2 and high if T1<T2.