Author Identifier
J. C. Wang: https://orcid.org/0000-0003-2476-928X
L. C. Zhang: https://orcid.org/0000-0003-0661-2051
Document Type
Journal Article
Publication Title
Materials Science and Engineering: A
Volume
925
Publisher
Elsevier
School
Centre for Advanced Materials and Manufacturing / School of Engineering
Funders
Edith Cowan University (23965) / National Natural Science Foundation of China (52404382) / Australian Government Research Training Program Scholarship / Forrest Research Foundation / TechWorks FutrueLab at The University of Western Australia / Woodside Energy Group Ltd
Abstract
Compared to other loading conditions, studies on deformation mechanisms of additive manufacturing (AM)-produced β-type Ti alloys under bending remain limited. This study investigates a metastable β-type Ti–25Nb–3Zr–3Mo–2Sn (TLM, wt.%) alloy fabricated via laser powder bed fusion (L-PBF) during in-situ three-point bending. In-situ observations using scanning electron microscopy (SEM) combined with electron backscatter diffraction (EBSD) and ex-situ transmission electron microscopy (TEM) imaging during bending provided evaluation of microstructural changes and deformation mechanisms. These mechanisms are characterized by dislocation slip, {332}<113>β deformation twin, α" phase, and ω phase formation during plastic bending stage. The {112}<111> slip system dominates in the compression zone, while the {123}<111> slip system governs in the tension zone during bending. The synergistic effect of twinning-induced plasticity (TWIP) and transformation-induced plasticity (TRIP) significantly enhances the ductility of L-PBF-produced TLM alloy. The deformation involves stress-induced α" and ω phases, with the latter can form within grains/twinning band and at twinning boundaries. Importantly, the presence of the interfacial twin boundary (ITB)-ω thin layers at twinning band boundaries exerts a pinning effect, restraining the outward extension of stress-induced α" phase. This mechanism suggests optimized utilization of space within twinning bands, facilitating α" nucleation and uniform growth, thereby providing insights into further enhancing ductility.
DOI
10.1016/j.msea.2025.147873
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Comments
Ma, H. Y., Wang, J. C., Liu, Y. J., Li, Y. H., Zhang, Y. S., Liu, X. C., & Zhang, L. C. (2025). In-situ microstructural evolution and deformation mechanisms of metastable beta titanium fabricated by laser powder bed fusion under flexural stress. Materials Science and Engineering: A, 925, 147873. https://doi.org/10.1016/j.msea.2025.147873