Anisotropic elastic and thermodynamic properties of the HCP-Titanium and the FCC-Titanium structure under different pressures
Publikationen: Beitrag in Fachzeitschrift › Artikel › Forschung › (peer-reviewed)
Standard
in: Journal of Materials Research and Technology, Jahrgang 9.2020, Nr. 3, 22.02.2020, S. 3488-3501.
Publikationen: Beitrag in Fachzeitschrift › Artikel › Forschung › (peer-reviewed)
Harvard
APA
Vancouver
Author
Bibtex - Download
}
RIS (suitable for import to EndNote) - Download
TY - JOUR
T1 - Anisotropic elastic and thermodynamic properties of the HCP-Titanium and the FCC-Titanium structure under different pressures
AU - Hao, P. D.
AU - Chen, P.
AU - Deng, L.
AU - Li, F. X.
AU - Yi, J. H.
AU - Şopu, Daniel
AU - Eckert, Jürgen
AU - Tao, J. M.
AU - Liu, Y. C.
AU - Bao, R.
N1 - Publisher Copyright: © 2020 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
PY - 2020/2/22
Y1 - 2020/2/22
N2 - Stress induced phase transformation from hexagonal close-packed titanium (HCP-Ti) to face-centered cubic titanium (FCC-Ti) is believed to be a reason for the pronounced work hardening of carbon nanotube-reinforced titanium (CNT/Ti) composites prepared by high-pressure torsion (HPT). Here, the correlation between the phase transformation from the HCP-Ti to the FCC-Ti structure in Ti and the improved mechanical properties of CNT/Ti composite is revealed by investigating the structural transformation mechanism, the stability, electronic properties, anisotropic elasticity and thermodynamics of the FCC-Ti and HCP-Ti crystals under pressure of 0-15GPa by means of first-principles calculations and comparing with the experimental findings. The results show that the formation enthalpies δHTi, the bulk modulus B, the shear modulus G and the Young's modulus E of the FCC-Ti and HCP-Ti structures gradually increase with increasing pressure, and the hybridization between the electronic orbitals of the atoms becomes stronger. The Young's modulus of the cubic FCC-Ti structure shows strong anisotropy along the [0 1 0] and [1 10] directions, while the HCP-Ti structure exhibits an obvious anisotropy of E in the (1 0 0) crystal plane. The thermodynamic stability of the HCP-Ti and FCC-Ti structures decreases under high pressure. The different relative stability of the two structures results in a high propensity of structural transformation from the HCP-Ti to the FCC-Ti structure. A large number of FCC-Ti structures are prepared, which can effectively improve the mechanical properties of CNT/Ti composites. Our results may help to better understand the phase transition from HCP-Ti to FCC-Ti under high pressure, and may reveal the structure-property relationship of CNT/Ti composites.
AB - Stress induced phase transformation from hexagonal close-packed titanium (HCP-Ti) to face-centered cubic titanium (FCC-Ti) is believed to be a reason for the pronounced work hardening of carbon nanotube-reinforced titanium (CNT/Ti) composites prepared by high-pressure torsion (HPT). Here, the correlation between the phase transformation from the HCP-Ti to the FCC-Ti structure in Ti and the improved mechanical properties of CNT/Ti composite is revealed by investigating the structural transformation mechanism, the stability, electronic properties, anisotropic elasticity and thermodynamics of the FCC-Ti and HCP-Ti crystals under pressure of 0-15GPa by means of first-principles calculations and comparing with the experimental findings. The results show that the formation enthalpies δHTi, the bulk modulus B, the shear modulus G and the Young's modulus E of the FCC-Ti and HCP-Ti structures gradually increase with increasing pressure, and the hybridization between the electronic orbitals of the atoms becomes stronger. The Young's modulus of the cubic FCC-Ti structure shows strong anisotropy along the [0 1 0] and [1 10] directions, while the HCP-Ti structure exhibits an obvious anisotropy of E in the (1 0 0) crystal plane. The thermodynamic stability of the HCP-Ti and FCC-Ti structures decreases under high pressure. The different relative stability of the two structures results in a high propensity of structural transformation from the HCP-Ti to the FCC-Ti structure. A large number of FCC-Ti structures are prepared, which can effectively improve the mechanical properties of CNT/Ti composites. Our results may help to better understand the phase transition from HCP-Ti to FCC-Ti under high pressure, and may reveal the structure-property relationship of CNT/Ti composites.
KW - Anisotropy
KW - Mechanical properties
KW - Nanocrystalline structure
KW - Thermodynamic properties
UR - http://www.scopus.com/inward/record.url?scp=85083467709&partnerID=8YFLogxK
U2 - 10.1016/j.jmrt.2020.01.086
DO - 10.1016/j.jmrt.2020.01.086
M3 - Article
AN - SCOPUS:85083467709
VL - 9.2020
SP - 3488
EP - 3501
JO - Journal of Materials Research and Technology
JF - Journal of Materials Research and Technology
SN - 2238-7854
IS - 3
ER -