Hot deformation behavior and globularization mechanism of Ti-6Al-4V-0.1B alloy with lamellar microstructure were quantitatively studied through isothermal compression tests with the temperature Hot deformation behavior and globularization mechanism of Ti-6Al-4V-0.1B alloy with lamellar microstructure were quantitatively studied through isothermal compression tests with the temperature range of 850-950 °C and strain rate range of 0.01-1.00s-1 . The results show that the peak flow stress and steady stress are sensitive to the strain rate and temperature. The value of deformation activation energy is 890.49 kJ mol-1 in (α+β) region. Dynamic recrystallization is the major deformation mechanism. Flow softening is dominated by dynamic recrystallization at 850-950 °C. TiB particles promote the recrystallization of a laths. Globularization processes consist of four steps: formation of subgrain after dynamic recovery in α plates; subgrain boundary migration caused by α/β interfacial instability; interfacial migration promoting β phase wedge into α phase; disintegrating of α laths by diffusion processes; and grainboundary sliding. Globularization mechanisms during hot deformation processes of the Ti-6Al-4V-0.1B alloy with lamellar structure are continuous dynamic recrystallization.
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