Effects of the number of equal-channel angular pressing passes on the anisotropy of ultra-fine titanium

Effect of ECAP numbers on microstructure and properties of titanium matrix composite

“…6), while the tensile strength decreases slightly after four passes. The decrease of strength and the increase of ductility could be the interaction of refinement and working hardening [19]. During the third ECAP pass, the refinement of TiB fibers and TiC particles would enhance the dislocations, which results in dislocation density increasing quickly in the boundary of the refinements, and the work hardening phenomenon is serious.…”

Formation of nanocrystalline β structure in metastable beta Ti alloy during high pressure torsion: The role played by stress induced martensitic transformation

“…Superior mechanical properties offered by ultrafine grained (UFG) materials such as high strength, good fatigue resistance and superplasticity at low temperatures [3] make SPD processes attractive. In particular, UFG titanium alloys have received considerable attention for potential aerospace and biomedical applications, including pure titanium [4][5][6][7] and a/b alloys [8,9]. However, the HCP structured a phase dominates in these alloys, making them difficult to process by SPD [10].…”

Thermomechanical coupling simulation and experimental study in the isothermal ECAP processing of Ti-6Al-4V alloy

“…Smolyakov et al [9] proposed a variation-difference method for solving continuum mechanics equations to simulate the ECAP process and studied the effect of processing parameters on the stress and strain distribution over the cross-section of ECAP samples. Korshunov et al [10] investigated the annealed commercial pure titanium processed by four ECAP passes at 450°C via route B C , in which the repeated rotation angle around the longitudinal billet axis before reinsertion in the die was 90°, and found that the anisotropy after all the ECAP passes of processing is similar at both room temperature and elevated temperatures. Zhao et al [11] observed that the shear bands and deformation twins occurred in the post-ECAP commercial pure titanium at high temperatures, and the slightly-increased yield strength and the ultimate strength of the post-ECAP pure titanium at higher temperatures can be obtained.…”