| Autor: |
Yu Wang, Yutong Jin, Yumeng Guo, Kai Chen, Zulei Liang, V.D. Sitdikov, Yuecheng Dong, Hui Chang, I.V. Alexandrov |
| Jazyk: |
angličtina |
| Rok vydání: |
2024 |
| Předmět: |
|
| Zdroj: |
Journal of Materials Research and Technology, Vol 31, Iss , Pp 1853-1863 (2024) |
| Druh dokumentu: |
article |
| ISSN: |
2238-7854 |
| DOI: |
10.1016/j.jmrt.2024.06.164 |
| Popis: |
In this paper, nano-Ti-2Fe-0.1B alloys with different grain sizes were processed by high pressure torsion (HPT) deformation. The study examined the microstructural evolution of the Ti–2Fe-0.1B alloy during HPT and evaluated its mechanical properties through microhardness and tensile tests. The results of the microstructural observations revealed that the grain size of the Ti–2Fe-0.1B alloy progressively decreased from 3.14 μm in the as-annealed state to approximately 20 nm after 10 turns. In the initial state, the alloy consists of α-phase and β-phases, with a volume ratio of approximately 5:1. During the HPT process, transformations of α-phase and β-phase to ω-phase were observed. The primary reason for this is that the shear forces applied during the HPT process facilitated the phase transformation of the α-phase. Additionally, the presence of Fe element in the alloy altered the lattice compatibility between the grains of β-phase and ω-phase, thereby promoting the phase transformation of the β-phase, with the accumulated turns of HPT process, the fraction of ω-phase increased in the beginning gradually, then decreased, which reached to the maximum 80.8% in the 5 turns. This is higher than that of pure titanium and Ti–Fe alloys under the same conditions, because the proportion of the ω-phase increases with the increase in Fe content. Studies of mechanical properties demonstrated that HPT can substantially enhance the hardness of Ti–2Fe-0.1B alloys to as high as 483 HV, and the tensile strength of the Ti–2Fe-0.1B alloy was observed to increase from 725 MPa to 1568 MPa after 5 turns, which is much higher than Ti–6Al–4V subjected to the identical processing conditions. It can be ascribed to the exist of mass ω-phase as well as finer grain size in nanocrystalline Ti–2Fe-0.1B alloy. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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