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Materials Science in Additive Manufacturing L-PBF Ti-10Ta-2Nb-2Zr: Microstructure and Strength

powder bed, resulting in finer microstructural features, demonstrate an elastic modulus of 9.2 – 9.7 GPa,
while central regions undergo slower cooling due to representing approximately 18% of the solid material
thermal mass effects, producing coarser microstructural value. Among the investigated topologies, the
elements. This thermal gradient creates variations in gyroid structure showed the best reproducibility
residual stress distribution, phase constitution, and of mechanical properties due to uniform stress
dislocation density throughout the strut cross-section. distribution. Microstructural analysis of porous
However, the mechanical behavior of lattice structures elements revealed a gradient from fine acicular
is governed by the overall microstructural homogeneity structure at the periphery to coarser lamellar structure
achieved through optimized L-PBF parameters rather in central regions, providing an optimal combination
than local microstructural variations. The consistent of strength and ductility.
yield strength values of 194 – 208 MPa across different The obtained results confirm the high potential of the
TPMS types demonstrate that the Ti-10Ta-2Nb-2Zr Ti-10Ta-2Nb-2Zr alloy for the additive manufacturing of
alloy maintains stable mechanical properties regardless orthopedic implants using the L-PBF process.
of local thermal gradients. The excellent reproducibility
observed, particularly in gyroid structures, indicates Acknowledgments
that the microstructural quality achieved through the
optimized processing window ensures reliable mechanical None.
performance of complex geometries.
Funding
4. Conclusion This research was supported by the Ministry of Science and
A comprehensive investigation of Ti-10Ta-2Nb-2Zr Higher Education of the Russian Federation (agreement
alloy fabricated using L-PBF enabled the establishment No. 075-15-2024-562).
of optimal processing regimes and characterization of Conflicts of interest
structural-phase state and mechanical properties for
biomedical applications. The authors declare they have no competing interests.
(i) Systematic variation of L-PBF parameters revealed an
optimal processing window: Laser power 250 – 280 W, Author contributions
scanning speed 600 – 800 mm/s, corresponding to Conceptualization: Igor Polozov, Anatoly Popovich
volumetric energy density of 62.5 – 93.3 J/mm . Within Formal analysis: Igor Polozov, Victoria Nefyodova, Anton
3
this range, a maximum relative density of 99.91% Zolotarev
was achieved, ensuring high mechanical integrity Investigation: Igor Polozov, Anton Zolotarev, Victoria
of components. Exceeding these energy parameters Nefyodova
leads to keyhole porosity formation, reducing material Methodology: Igor Polozov, Anatoly Popovich
density. Project administration: Igor Polozov
(ii) Microstructural analysis showed the formation of Resources: Anatoly Popovich
predominantly martensitic α’-phase in the as-built Supervision: Anatoly Popovich
condition with characteristic acicular morphology due Writing – original draft: Igor Polozov
to high cooling rates during L-PBF. DSC determined Writing – review & editing: Anatoly Popovich, Victoria
β-transus temperature at 862°C. Heat treatment at Nefyodova
900°C provides complete recrystallization with the
formation of equilibrium lamellar α + β structure, Ethics approval and consent to participate
confirmed by XRD analyses. Not applicable.
(iii) Mechanical properties of Ti-10Ta-2Nb-2Zr alloy in
as-built condition are characterized by high strength Consent for publication
characteristics: yield strength 551.8 MPa, ultimate
tensile strength 641.2 MPa, with elongation of 19.0% Not applicable.
and elastic modulus of 89.0 GPa. Heat treatment Availability of data
reduces strength properties by 15 – 18% but decreases
elastic modulus to 86.0 GPa, bringing it closer to the The datasets used and/or analyzed during the current
properties of bone tissue. study are available from the corresponding author on
(iv) Developed porous structures based on TPMS (gyroid, reasonable request. Raw data files for mechanical testing,
Schwarz, and split) with 50% volumetric porosity microstructural analysis, and selective laser melting

Volume 4 Issue 3 (2025) 14 doi: 10.36922/MSAM025220044