Seznam abstraktů 2026: SEKCE E - NEŽELEZNÉ KOVY A SLITINY

Additive manufacturing (AM) has introduced a practical route to fabricate complex, patient-specific metallic implants with controlled architectures that are difficult to achieve through conventional processing. Titanium alloys, in particular, remain central to biomedical applications because they combine high specific strength, corrosion resistance, and biological compatibility. Among them, Ti-6Al-4V has been extensively used due to its well-balanced mechanical properties, fatigue resistance, and stable oxide layer. However, the long-term release of vanadium ions under physiological conditions has raised concerns regarding cytotoxicity, which has driven the search for safer alloying elements. Niobium offers a viable alternative in this regard, as it is considered biologically inert and contributes to phase stability and corrosion resistance. This has led to the development of Ti-6Al-7Nb as a potential replacement alloy. In the present work, Ti-6Al-7Nb was produced using selective laser melting, and its microstructural features and mechanical response were examined and compared with conventionally processed Ti-6Al-4V, which serves as a practical benchmark due to its widespread clinical use. Since titanium alloys are inherently prone to wear, particularly under simultaneous mechanical and electrochemical exposure, their tribocorrosion behavior was further evaluated. To address surface-related limitations, laser shock peening was applied as a post-processing step, and its influence on microstructural evolution and mechanical performance was assessed. The outcomes provide a clearer understanding of how processing, composition, and surface modification interact, which is relevant for improving the durability of titanium-based biomaterials in demanding service environments.

Third‑generation Al-Li alloys differ from earlier generations by their lower Li content and the resulting changes in the primary strengthening phases. Since conventional processing routes have largely reached their limits for improving the mechanical properties of these alloys, alternative approaches, such as rapid solidification, are increasingly being explored. Rapidly solidified materials can achieve exceptional properties after consolidation due to their refined microstructure and enhanced supersaturation of the solid solution.
Melt‑spinning of an Al-Cu-Li-Mg-Zr-Sc alloy produces ribbons with an extremely fine microstructure but also pronounced structural gradients across the ribbon thickness. The as‑cast ribbons exhibit two distinct solidification zones: a wheel‑side region containing columnar cells with fine Cu‑rich spherical precipitates, and a central region composed of larger eutectic cells enriched in Al₂Cu and Al₇Cu₂Fe phases.
In‑situ TEM annealing between 200 and 500 °C reveals a sequence of phase transformations, including the formation and subsequent coarsening of strengthening precipitates. In alloys containing Zr and Sc, Al₃(Sc,Zr) core-shell dispersoids also form. Above 500 °C, rapid dissolution of primary phases and coarsening of strengthening particles occur. This is followed by coagulation of Fe‑ and Cu‑containing phases into a limited number of stable grain‑boundary particles, which eliminates the original two‑zone structure and results in a fully homogenized ribbon.

Low alloyed 1XXX series aluminum alloys are widely used due to their excellent electrical and thermal conductivity, high corrosion resistance, and superior formability. However, their relatively low mechanical strength limits their applicability in environments involving elevated temperatures. In applications where components may be exposed to thermal loads approaching 200 °C, additional softening can occur, even when prior mechanical deformation has introduced a degree of strengthening. To enhance thermal stability, alloying elements such as Zr are commonly added to promote solid solution strengthening and to form thermally stable Al₃Zr dispersoids that inhibit recovery and recrystallization.
While these alloys are traditionally produced by direct chill (DC) casting, continuous casting (CC) has seen increasing adoption due to its higher processing efficiency. A known drawback of CC, however, is the potential development of through thickness inhomogeneities in mechanical properties, which can significantly affect the subsequent forming of thin sheets or thin walled products.
In this study, an experimental EN AW 1050A alloy containing a small addition of Zr was produced via continuous casting and subsequently subjected to hot rolling and cold rolling to achieve a total thickness reduction of 80%, followed by annealing at 500 °C. Despite this thermomechanical treatment, the material exhibited microhardness variations of approximately 10-20% across the strip thickness. These results indicate that neither extensive deformation nor exposure to elevated temperature fully eliminates the intrinsic microstructural differences between the surface and central regions introduced during the CC process.

A composite chiller consisting of graphite foam infiltrated with pure zinc as a phase change material (PCM) and enclosed within a steel container was used to enhance heat transfer and accelerate the solidification of an Al-4.5 wt% Cu alloy. Cooling performance was evaluated using numerical simulation based on temperature-time diagrams, along with calculations of thermal gradient (G) and growth rate of the solidification front (R). The results were validated through comparison with available experimental data related to pure zinc as PCM and to conventional steel chillers. The results indicate that the porous foam structure increased the effective surface area and reduced the volume-to-surface ratio, enabling earlier melting of zinc and improving its heat absorption from the molten alloy. The Zn-graphite foam composite enhanced heat extraction during the early stages of solidification, reducing the solidification time compared to the other types of chillers. This promoted an ideal temperature distribution within the completely filled mould cavity, making the subsequent cooling path favourable to feeding. Higher thermal gradients were observed near the composite chiller. In all configurations, G/R decreased from the chiller toward the runner, indicating the potential for a columnar-to-equiaxed transition (CET); however, this reduction was more abrupt in the composite case, suggesting shorter columnar growth and accelerated CET. Consequently, a more equiaxed microstructure with reduced shrinkage defects is expected. Despite using less zinc, the high thermal conductivity of the graphite foam compensated for this reduction, demonstrating the superior efficiency of the Zn-graphite foam composite chiller.

Functionally graded materials belong to the group of advanced engineering materials, primarily due to their spatial variation of properties in one or multiple directions. Such materials exhibit improved surface and mechanical performance. The diffusion-based surface treatment processes of metallic components lead to enhanced fatigue strength while enabling the formation of a hard surface layer combined with a ductile substrate. However, these processes result in a complex stress state and local stress concentrations, particularly in the gradient-affected zone. The spatial variation of material properties in functionally graded materials necessitates a comprehensive analysis of the mechanisms controlling crack initiation and propagation.
Therefore, the aim of this study is to perform a numerical analysis of fracture mechanisms in metal-ceramic functionally graded materials.
The study investigates crack initiation and propagation based on material data available in the literature. The analyzed material system consisted of a titanium alloy substrate with a diffusion-formed nitrogen-enriched subsurface zone and an outer layer of hard titanium nitride (TiN). Numerical simulations were carried out assuming spatially varying material parameters, including Young’s modulus, hardness, and density as a function of distance from the material surface.
Based on the performed numerical simulations, the effect of the formed diffusion zone on crack initiation and subsequent propagation was identified. The obtained results may support the selection of surface treatment parameters aimed at improving the fatigue resistance of metallic structural components. The findings can serve as a good starting point for further optimization studies focused on fracture processes in components operating under variable thermal conditions.

The development of affordable and scalable SERS substrates remains a key challenge for chemical sensing applications. In this contribution, nanoporous copper (NPC) films are investigated as three-dimensional SERS-active platforms fabricated through a dynamic hydrogen bubbling template (DHBT) electrodeposition process, enabling the rapid synthesis of highly porous copper substrates.
A systematic investigation was carried out to correlate deposition time with the resulting structural and morphological features, including film thickness, pore distribution, and surface roughness. The incorporation of additive such as cetyltrimethylammonium bromide (CTAB) during electrodeposition significantly altered the pore architecture, yielding finer nanopores (about 13-24 μm) compared to those obtained without additives (about 27-73 μm). These morphological variations strongly influenced the SERS response of the substrates.
The sensing capability of the NPC films was assessed using methylene blue (MB) as a probe molecule. The highest SERS performance was achieved at a deposition time of 180 s for additive-free films and 120 s for CTAB-modified samples. Notably, the presence of CTAB led to improved detection efficiency, allowing MB to be detected down to a concentration of 10⁻⁶ M. Enhancement factors on the order of 10^3 were obtained for both types of substrates, confirming the suitability of NPC films for SERS applications.
Overall, this study demonstrates that controlled electrodeposition parameters and additive-assisted morphology tuning are effective strategies for optimizing copper-based SERS substrates, paving the way for low-cost and high-performance sensing platforms.

Zinc alloys are recognised for their excellent biocompatibility and favourable corrosion resistance, making them suitable candidates for bioabsorbable implants. The major challenge concerning the utilisation of zinc as a biodegradable material is, however, its unsatisfactory mechanical strength. Commonly, strengthening through alloying and grain refinement results in a significant increase in strength but a decrease in ductility. Harmonic grain structure, which combines soft, ductile large grains with hard, ultrafine grains, has been found to be highly effective in overcoming the strength-ductility trade-off. This synergetic effect is primarily attributed to the high strain-hardening capability enabled by the heterogeneous grain distribution, which effectively delays the onset of plastic instability. In our research, the harmonic structure was prepared via powder metallurgy. Coarse-grained pure zinc was consolidated with ultrafine-grained Zn-Mg(-Ag) milled powder by spark plasma sintering (SPS) to produce compacts with various fractions of individual constituents. The resulting samples were analysed using advanced microscopy techniques and uniaxial deformation tests to reveal the effects of composition and the ratio between the two structural types on the mechanical properties of the investigated alloys.

Bioresorbable metallic alloys represent a significant advancement in the development of temporary biomedical implants, offering a favorable balance between biocompatibility and controlled degradation. This study investigates the impact of a two-step equal-channel angular pressing (ECAP) processing route on the performance of a promising biodegradable alloy. The mechanical response was evaluated using uniaxial tensile tests at varying strain rates, while the microstructural evolution was characterized via synchrotron hard X-ray diffraction and transmission electron microscopy (TEM). The results demonstrate that the multi-step processing led to a remarkable simultaneous enhancement of both strength and ductility compared to the material's annealed state. Notably, at the lowest strain rate, the alloy exhibited a fracture elongation of up to 240% at room temperature—a unique manifestation of superplasticity under ambient conditions.Structural analysis confirmed the formation of an ultrafine-grained (UFG) microstructure and the activation of non-basal slip systems, which facilitated efficient plastic flow. These findings highlight that controlled severe plastic deformation is an effective strategy for tailoring the properties of bioresorbable alloys. This approach opens new possibilities for the design of next-generation, low-to-moderate load orthopedic fixation devices, such as plates, screws, and suture anchors, which eliminate the need for secondary removal surgeries.

The Ausmelt TSL pyrometallurgical process is efficient, environmentally friendly and flexible for processing a wide range of non-ferrous metal concentrates and secondary raw materials. The pursuit of environmentally friendly technologies and greater opportunities for processing a wide range of concentrates and various secondary materials has made this technological process the main one for lead smelting in recent decades.
As a model scheme, the one of KCM-AD, Plovdiv, Bulgaria - a major lead producer for Southeastern Europe - was used. The new lead plant combines the best available techniques in the metallurgical industry. The implemented high-tech scheme based on autogenous smelting of raw materials meets high environmental and energy European standards. Lead-containing raw materials are primary lead concentrates and secondary materials such as lead paste from the KCM spent battery plant, lead cakes from the zinc plant, as well as recycled dust. The plant has a complete cycle of processing raw materials and intermediate products by integrating technological schemes in lead and zinc production. The ratio between the metal content in primary and secondary raw materials is currently approximately 1:1.
The exergy and environmental study was carried out using the exergy method of thermodynamic analysis. The resources - primary and secondary raw materials, the products and emissions - gas emissions, wastewater and solid waste, and the methods used to minimize technogenic emissions were assessed.
Based on the circular economy, in the processing of concentrates, intermediate products and waste along the technological processing chains, in-depth and complex utilization of the raw materials used has been achieved.

The LaNi5 compound is a prototypical hydrogen-storage material intended for future energy applications. Some of its properties have not been sufficiently studied so far and some critically important data is missing. In particular, there are conflicting literature reports related to the substitution of Ni atoms with Sn atoms in LaNi5. We have employed quantum-mechanical calculations implementing the density functional theory (DFT) within the generalized gradient approximation (GGA) to determine the ground-state structural, electronic, thermodynamic, and vibrational properties of several substituted La(Ni,Sn)5 phases. Our computational cell containing 48 atoms allowed for simulating different Sn/Ni ratios as well as different configurations of substituting Sn atoms. Our results indicate that the free energy of formation is concave and there is a miscibility gap and a decomposition into two phases, one with a low and one with a high Sn concentration. Our theoretical study was complemented by experiments which found a similar miscibility gap, too.

In recent years, wastes generated during copper smelting have attracted growing attention not only as an environmental issue but also as a potential secondary source of economically and strategically valuable elements. Lead-bismuth sludge formed during wet gas cleaning is a chemically complex polymetallic material. Its composition is determined by the mineralogical characteristics of the processed feedstock as well as by the physicochemical conditions of high-temperature smelting and subsequent gas purification.
Selenium and tellurium are of particular interest because they are classified as critical raw materials and their primary natural sources are limited. According to material balance considerations, part of these elements is expected to redistribute into technogenic products formed during smelting. However, available published data on their actual concentrations in lead-bismuth sludge remain scarce and sometimes contradictory.
Although selenium and tellurium belong to the same group of chalcogen elements, their behavior under high-temperature oxidative conditions differs markedly. These differences affect their volatility, oxidation states, and their tendency to partition between solid and gaseous phases. Consequently, the enrichment of these elements in specific waste streams cannot be reliably predicted solely from ore composition and therefore requires experimental verification.
The aim of the present study is to perform a quantitative assessment of the elemental composition of lead-bismuth sludge formed during wet gas cleaning and to analyze the contrasting distribution behavior of selenium and tellurium in this technogenic material.

The long-term objective of this research is the development of a femoral stem fabricated from a metastable β-Ti alloy with a graded chemical composition, enabling a low elastic modulus in the bone-anchoring region and high strength in the load-bearing region. To achieve this goal, it is first necessary to verify that the individual compositions within the intended gradient independently exhibit the required mechanical and structural properties. Accordingly, the present study focuses on four homogeneous metastable β-Ti alloys selected to span the targeted compositional range.
All alloys were prepared by powder metallurgy under optimized conditions to obtain fully dense microstructures. Their properties were characterized using scanning electron microscopy, X-ray diffraction, microhardness measurements, tensile testing, and resonant ultrasound spectroscopy. The results show that the low-modulus alloy exhibits the desired elastic compliance, while the high-strength alloy provides enhanced mechanical performance. The intermediate compositions display stable and reproducible behavior, confirming the continuity of properties across the compositional range.
These findings demonstrate that all selected compositions meet key mechanical requirements, thereby establishing a basis for the development of compositionally graded Ti alloys for biomedical applications, where spatially tailored properties can be achieved through controlled chemical variation.

This study deals with the development and characterization of FeSi-NiAl-based composite materials, consisting of NiAl matrix and FeSi hardening phase, representing a new generation of tool materials. These composites can compete with conventional materials, such as cemented carbides and high-speed steels, which contain tungsten and cobalt - raw materials classified as critical by the European Union and economically burdened by the current geopolitical situation. The composites were prepared by vacuum induction melting with centrifugal casting in weight ratios of FeSi:NiAl - 1:2 and 2:1. In order to improve structural homogeneity and mechanical properties, the samples were subsequently remelted by the Bridgman directional solidification method at a temperature of 1450 °C with a holding time of 30 minutes and a crystallization rate of 100 mm/h. The microstructure was analyzed using scanning electron microscopy (SEM) and chemical composition was determined by energy dispersive X-ray spectroscopy (EDX). Furthermore, microhardness was evaluated using the Vickers method along with tribological properties, specifically the friction coefficient and wear rate, which are key for practical tool applications. In the as-cast state, the composites showed a randomly oriented dendritic microstructure. In contrast, directional solidification led to significant straightening of the microstructure and a controlled distribution of individual phases. This process resulted in a significant leveling of mechanical and tribological properties in both compositions compared to the as-cast state. This indicates higher structural homogeneity and more stable material behavior under operating conditions, making these composites suitable for advanced engineering applications.

The recent progress in additive manufacturing increased the demand for high quality metal powders with tailored composition. The refractory complex concentrated alloys are peculiar for conventional metallurgy due to their high melting point and reactivity. Therefore, the cold spray additive manufacturing method is ideal for utilization of this type of material. Radiofrequency plasma spheroidization provides powders with suitable collection of properties for further processing. In addition, the combination of our cold spray additive manufacturing and refractory complex concentrated alloys is suitable for cladding of heat sensitive parts. This work focuses on production of spherical powder of a selected refractory complex concentrated alloy Al0.5NbTa0.8Ti1.5V0.2Zr from a powder produced by high energy milling from elemental commercial powders. Various processing parameters will be discussed in order to optimize the quality, homogeneity and powder size distribution. Each additive manufacturing method requires different size distribution of powder particles. However, powder sieving significantly decreases efficiency of production. Therefore, provided optimization of milling and spheroidization processes are crucial. In addition, hydrides of selected metals were substituted for pure metals in order to investigate oxygen content variaton. Main focus of this study is to investigate microstructure and quantitative phase composition of spheroidized powder particles from initially mechanically alloyed powders with the atomic-level homogeneity. High-enthalpy plasma reaction in protective atmosphere liquifies intermixed powder particles and thus interesting microstructures and phase composition are formed during fast cooling in the collector and on the walls of the spheroidization chamber. Such powder does not require complicated heat treatment nor surface reduction annealing and is ready for further additive manufacturing. The first samples of cold spray additive manufacturing method of high entropy alloy Al0.5NbTa0.8Ti1.5V0.2Zr will be presented after thorough analyses of microstructure, quantitative phase composition and mechanical properties. Influence of titanium and zirconium hydrides addition will be discussed.

Plastic deformation in crystalline materials is governed by collective, intermittent dislocation dynamics that produce avalanche-like behavior and scale-invariant statistics. While such “crackling” plasticity is well established in model systems such as single-crystal micropillars, its relevance to structurally complex materials - particularly high-entropy alloys (HEAs) - remains insufficiently understood. In this study, we investigate plastic instabilities and microplasticity in FeAlCr-based medium-entropy alloys under compression, focusing on their connection to universal avalanche dynamics across length scales. Compression tests reveal pronounced serrated flow at elevated temperatures and intermediate strain rates. Mechanical testing is complemented by concurrent acoustic emission (AE), serving as a high-resolution proxy for elementary plastic events. Statistical analysis reveals power-law distributions of event energies, consistent with scale-free avalanche behavior. These results demonstrate that, despite their complexity, HEAs follow the same universal deformation dynamics as simpler systems, from micron-scale crystals to bulk materials, supporting a unified description of plasticity in terms of stochastic, self-organized dislocation avalanches.

High-entropy alloys (HEAs) derived from the Fe-Al-Ni system represent a promising pathway beyond conventional single-principal-element alloys. In this contribution, we examine the deformation mechanisms and plastic instabilities of selected Fe-Al-Ni-based HEAs under compressive loading, including elevated temperatures. Combined mechanical testing with in-situ acoustic emission (AE) monitoring and digital image correlation (DIC) reveals substantial microplastic activity already in the quasi-elastic regime. With increasing strain, the alloys exhibit serrated flow characteristic of the Portevin-Le Châtelier effect, indicating dynamic strain aging driven by solute-dislocation interactions. Statistical analysis of AE signals shows power-law scaling of event energies, consistent with scale-invariant dislocation avalanche dynamics. Notably, this critical-like behavior persists across deformation stages, linking early microplasticity to macroscopic plastic flow and highlighting the intrinsically collective nature of plastic deformation in these chemically complex systems.

The intermetallic phase LaNi5 is known as a material for reversible hydrogen storage due to its suitable thermodynamic properties, and relatively fast kinetics of hydrogen absorption and desorption with the formation of LaNi5H7 hydride. This work focuses on the synthesis and characterization of a modified LaNi5 phase with the addition of indium. The aim is to influence the microstructure and hydrogen storage properties of this material.
The samples were prepared by melting in an arc melting furnace under an inert atmosphere of pure argon and then annealed for a long time to establish a thermodynamic equilibrium state. Chemical composition and structural characterization were performed using X-ray diffraction (XRD) and electron microscopy (SEM) to identify present phases. Attention was paid to the effect of indium addition on the stability of the intermetallic structure and the stability of any secondary phases and subsequently produced hydrides.
The thermodynamic hydrogenation properties of the prepared alloys were studied by measuring pressure-concentration isotherms (p-c-T curves) during hydrogen absorption and desorption cycles. The experiments made it possible to determine the maximum hydrogen storage capacity and enthalpy and entropy of the process. The results suggest that modifying the LaNi5 alloy with indium can affects the thermodynamics and kinetics of hydrogen storage process, as well as maximum hydrogen storage capacity.
ACKNOWLEDGMENTS: This study is a part of the project No. CZ.02.01.01/00/22_008/0004631 Materials and technologies for sustainable development within the Jan Amos Komensky Operational Program financed by the European Union and from the state budget of the Czech Republic.

In the past, zirconium alloys with only low concentrations of alloying elements have predominantly been studied, mainly to maintain a low neutron capture cross-section for nuclear applications. However, zirconium alloys represent a broader class of materials with promising properties that remain insufficiently explored.
Zirconium belongs to the same group in the periodic table as titanium, and therefore knowledge of phase transformations in titanium alloys can provide a useful framework for understanding zirconium-based systems.
In this work, phase transformations in metastable β zirconium alloys based on the Zr-Nb system were investigated in situ using high-energy synchrotron X-ray diffraction. The results were correlated with measurements of electrical resistivity, heat flow, and dimensional changes during linear heating at a rate of 5 °C/min. The experimental analysis was complemented by direct microstructural observations using scanning and transmission electron microscopy (SEM and TEM).
The results reveal a phase transformation sequence similar to that known for titanium alloys; however, several important differences were identified. In particular, two distinct BCC β phases with different lattice parameters were observed in zirconium alloys. Furthermore, while ellipsoidal ω-phase particles are typically reported in titanium alloys, cuboidal particles were identified in the present zirconium system.

This study reports on the characterization and synthesis of the 2D carbon-based materials. In here, Ti, Si and graphite are used as starting materials. Firstly, powders with varying molar ratios of Ti, Si, and C (1:1:1, 2:1:1, 3:2:1, and 3:1:2) totaling 6 g were prepared, and 1 wt.% stearic acid was added to prevent cold welding. The powders were mechanically alloyed (MA) for 3 h using stainless steel vials and balls, with a ball-to-powder weight ratio of 10:1. After MA, the powders were placed in molds and shaped using a cold isostatic press at 2400 MPa pressure for 120 sec. The shaped compositions were first debinded at 420 °C for 30 min to remove the stearic acid. Subsequently, the bulk compositions were annealed at 1400 °C for 3 h to obtain the MAX phases. After crushing the annealed bulk compositions, etching was performed to remove Si content. 10 ml of 6 M hydrofluoric acid was used for 1 g of powder. After mixing the powders for 48 h, they were repeatedly washed with distilled water until the pH reached between 6-7. The washed powders were left in an oven for 24 h for drying. Phase analysis, microstructure analysis, Brunauer-Emmett-Teller analysis, particle size and density measurements of the powders were performed. Ti3SiC2, SiC and TiC were seen in the structure. Also, TiSiC (3:1:2) has the highest (~ 4.43 g/cm3) and TiSiC (1:1:1) has the lowest density (~ 3.45 g/cm3). The average particle size of the compositions is ~ 5 μm.

Layered LiNiₓCoᵧMn₁₋ₓ₋ᵧO₂ (NMC) materials represent one of the most widely used cathode active materials for lithium-ion batteries in automotive applications due to their high specific capacity and relatively low production cost. However, NMC cathodes, particularly those with a high nickel content, are known to be sensitive to the ambient atmosphere. Exposure to air may lead to moisture absorption and reactions with carbon dioxide, resulting in the formation of surface impurities that can negatively influence electrochemical performance [1].
The present study focuses on the characterization of the NMC811 cathode in its pristine state and after storage in ambient conditions for different exposure times (1, 2, and 3 months). The aim is to evaluate changes in the microstructure, morphology, and phase composition of the cathode material caused by interaction with the surrounding atmosphere.
Surface morphology and cross-sectional microstructure were examined using scanning electron microscopy, while elemental distribution was analyzed by energy-dispersive X-ray spectroscopy. Structural characterization of the cathode active material was performed by X-ray diffraction using both conventional Theta-2Theta and grazing incidence configurations. Thermal behavior and phase transformations during heating and cooling were investigated using differential scanning calorimetry, while mass changes were monitored by thermogravimetric analysis. Chemical changes were further analyzed by Fourier-transform infrared spectroscopy (FTIR).
The results revealed the formation of surface impurities such as LiOH and Li₂CO₃ after storage under ambient conditions. Their concentration increased with longer exposure times, indicating progressive surface degradation of the cathode material. In addition, signs of cation mixing were observed, with more pronounced structural changes detected near the surface compared to the bulk of the material.

Reference:
[1] W. Li et al., Nat. Energy 5 (2020) 26-34.

Acknowledgements:
Funded by the EU NextGenerationEU through the Recovery and Resilience Plan for Slovakia under the project No. 09I04-03-V02-00046.

Boriding of Ti6Al4V titanium alloy produces dual-phase boride layers composed primarily of a continuous outer TiB2 layer and an inner TiB whisker sub-layer. The formation of these layers significantly enhances surface hardness and wear resistance, making the alloy more suitable for demanding aerospace and biomedical applications. The growth kinetics of the boride layers follows a temperature-dependent parabolic law governed by boron diffusion. Microstructural analysis reveals a compact, smooth morphology with strong adhesion to the substrate. The addition of elements such as niobium further modifies the microstructure by forming niobized layers, improving mechanical properties including microhardness and fracture toughness. This thermochemical surface treatment presents a promising route for extending the service life and performance of Ti6Al4V components.