Effect of Ti on surface energy, unstable stacking energy, Peierls-Nabarro potential energy and fracture behavior of Nb
Year: 2025
Type: article
Abstract: In this work, the cell structure models of Nb alloy with different Ti contents (0, 11.1 at.%Ti and 25at.%Ti (referred as to Nb-0Ti, Nb-11.1Ti and Nb-25Ti alloys, hereafter) were established by the first principle, and the surface energy (γs), unstable stacking energy ( ), and Peierls-Nabarro potential energy (UP-N) of dislocation on different slip systems were calculated. The deformation and toughening behaviors of Nb dependent on the Ti contents were investigated and discussed. The results revealed that the UP-N values of the edge and screw dislocations on the low Miller indices {1 1 0} planes were lower than those on the high Miller indices {1 1 2} and {1 2 3} planes. With an increasing Ti content from 0 to 25 at.%, the UP-N values on the corresponding slip systems ({1 1 0}, {1 1 2} and {1 2 3}) significantly decreased, which were resulted from decreasing of the anisotropic shear modulus c and the bond strength of Nb-Ti, while the fracture toughness (KQ) of the bulk Nb-Ti alloys increased from 21.1 (MPa·m1/2) to 45.7 (MPa·m1/2). It was confirmed that with the Ti addition the decreasing UP-N value leads to slipping of more <1 1 1>{1 1 2}dislocations in addition to the <1 1 1>{1 1 0} dislocations, subsequently, increases the dislocation density and the proportion of the screw dislocation, and finally improves the KQ values of the Nb-Ti alloys with a dimple dominated fracture mode.
Authors: Yuanyuheng Wang, Pei Yuwen, Youxing Yu, Jiangbo Sha
Institution: Beihang University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,310
OpenAlex ID: W4417027795