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

neutral alloying element, can improve strength without (iii) Establishing correlations between processing
significantly affecting phase stability and has been reported parameters, microstructural features, and resulting
to enhance the corrosion resistance of Ti alloys. The mechanical properties, particularly regarding elastic
reduced Ta content (10 wt.%) offers substantial economic modulus reduction, which is critical for biomedical
advantages compared to higher Ta content alloys while applications;
potentially retaining most of the beneficial properties (iv) Determining optimal processing windows and thermal
associated with Ta addition. The significance of this alloy treatment regimes to achieve the best combination of
lies in its elimination of potentially toxic elements (Al, V) properties for orthopedic implants;
present in conventional Ti-6Al-4V, making it more suitable (v) Designing and evaluating the influence of TPMS
for long-term biomedical applications. Furthermore, the lattice structures made from Ti-10Ta-2Nb-2Zr alloy
combination of optimized chemical composition with on mechanical properties.
advanced manufacturing techniques, such as laser powder Through this comprehensive investigation, we aim to
bed fusion (L-PBF), enables the development of complex advance the understanding of process–structure–property
porous architectures that can achieve elastic modulus relationships in this promising biomedical alloy and
values approaching those of natural bone tissue. This contribute to the development of improved Ti implants
dual approach of compositional design and structural with enhanced biomechanical compatibility.
engineering represents a promising strategy for next-
generation orthopedic implants with enhanced mechanical 2. Materials and methods
compatibility. 2.1. Starting materials
Traditional manufacturing methods for Ti-Ta The primary material used in this investigation was pre-
alloys include casting, forging, and powder metallurgy alloyed Ti-10Ta-2Nb-2Zr powder (Guangzhou Sailong
approaches, each presenting specific challenges in utilizing Additive Manufacturing Co., Ltd., China). The powder
Ta due to its high melting point, segregation issues, and particles exhibited predominantly spherical morphology
difficulties in achieving homogeneous microstructures. 26,27 with satellite particles occasionally present on larger
L-PBF, an additive manufacturing method, offers distinct spheres (Figure 1A). Particle size distribution analysis
advantages for processing these alloys, including the ability performed using a laser analyzer (Fritsch Analysette 22,
to create complex, patient-specific geometries, reduced NanoTec plus, Germany) showed a size distribution with
material waste, and potentially improved microstructural d = 11.3 μm, d = 29.1 μm, and d = 61.7 μm (Figure 1B).
control through rapid solidification conditions. 14,16 10 50 90
However, processing Ti-Ta-based alloys using L-PBF Scanning electron microscopy (SEM) examination
introduces challenges, including the need to optimize of the powder particles revealed surface morphology
processing parameters to achieve high density, desired characterized by fine dendritic structures typical of rapid
microstructures, and stable mechanical properties. solidification during gas atomization (Figure 1C). Cross-
sectional analysis combined with energy-dispersive
Previous studies of L-PBF Ti alloys containing Ta X-ray spectroscopy (EDS) mapping confirmed uniform
and other β-stabilizers have demonstrated the feasibility distribution of Ti, Ta, Nb, and Zr elements within individual
of achieving high-density components with promising particles, demonstrating good compositional homogeneity
mechanical properties. However, the influence of specific (Figure 1D). Chemical analysis of the powder showed
L-PBF processing parameters on densification behavior, the following composition (wt.%): Ti: Balance; Ta: 9.85 ±
microstructural evolution, and mechanical properties of 0.18%; Nb: 1.95 ± 0.12%; Zr: 1.92 ± 0.10%.
the Ti-10Ta-2Nb-2Zr alloy has not been systematically
investigated. Furthermore, the effect of thermal treatments 2.2. L-PBF
on phase transformations, microstructural stabilization, Samples were fabricated using an L-PBF system (MINI,
and mechanical behavior of this alloy remains largely 3DLAM, Russia) equipped with a fiber laser IPG
unexplored. Photonics, USA) with a maximum power of 300 W and
The present study aims to address these research gaps a beam diameter of 70 μm. Processing was conducted in
by: a high-purity argon atmosphere (O < 100 ppm) on a Ti
2
(i) Systematically investigating the influence of L-PBF build platform without pre-heating. The building strategy
processing parameters on density, microstructure, and featured a linear scanning pattern with 90° rotation
mechanical properties of the Ti-10Ta-2Nb-2Zr alloy; between consecutive layers for bulk volumes.
(ii) Studying phase transformation behavior and The selection of processing parameters was based on
microstructural evolution during thermal treatments; our previous experience with similar Ti alloys, where

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