Low-temperature power spinning of commercially pure titanium tubes: strengthening at lower wall-thickness reductions

Liquid‑nitrogen-assisted low-temperature (CT) power spinning was compared with room-temperature (RT) spinning of TA2 commercially pure titanium (CP-Ti) tubes. CT-27.2 reached 591.0 ± 8.7 MPa UTS, exceeding RT-40 (566.4 ± 10.9 MPa) at lower reduction; CT-37.6 reached 641.9 ± 8.1 MPa, close to RT-60 (654.9 ± 9.2 MPa), while retaining higher YS, elongation, and tensile work to fracture. Three-field EBSD statistics showed pronounced compression twinning at CT-10 and progressive intragranular subdivision with reduction. At the near-matched RT-40/CT-37.6 states, LAGB fractions were 49.6 ± 1.7% and 52.6 ± 2.3%, while compression-twin-boundary fractions were 11.1 ± 1.0% and 15.8 ± 1.4%. The results show that the CT route can accumulate high strength at smaller wall-thickness reductions through stronger early twinning and subsequent boundary subdivision.