To investigate microstructural evolution and homogenization in near–α titanium alloy under large-strain multi-pass hot rolling, a three-pass rolling experiment was conducted on TA16 alloy from Φ180 mm to Φ14 mm. Electron backscatter diffraction (EBSD) was employed to systematically characterize the microstructure, kernel average misorientation (KAM), and texture at the center, mid-radius, and edge locations for each stage. The room-temperature tensile properties of the final wire were also tested. The results show that hot rolling induces sequential microstructural evolution: equiaxed coarse grains → elongated duplex grains → bimodal equiaxed grains → homogeneous ultrafine deformed grains. The evolution of KAM values (from 0.68° to 1.41° to 0.80° to 1.13°) comprehensively reveals the dynamic process of deformation stored energy: "accumulation → release → re-accumulation". The formation of the final microstructure is dominated by "ultimate grain fragmentation" and "dynamic recovery", characterized by ultrafine grains (∼2.6 μm 2 ), a low recrystallized fraction (∼7.4%), and substructures with a high dislocation density. Quantitative strength analysis demonstrates that grain refinement strengthening and dislocation strengthening contribute approximately 52% and 35%, respectively, constituting the primary strengthening mechanisms. This enables the material to achieve a synergistic combination of high strength (tensile strength: 655 MPa, yield strength: 510 MPa) and good ductility (elongation after fracture: 20%). Furthermore, a strong basal fiber texture of //RD remains stable throughout the entire process. This work proposes a mechanism to fabricate balanced strength-ductility ultrafine microstructures via the "work-hardening → softening → fragmentation" pathway, offering a new strategy for short-process manufacturing of high-performance TA16 alloy.
Qiang et al. (Sun,) studied this question.