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A series of Sr0.7Ba0.3Nb2O6−δ/x wt. % Ti (x = 1, 3, 5, and 10) composite ceramic thermoelectric materials were prepared, and the mechanism for improving their thermoelectric properties was explored. The experimental results demonstrate that nano-additive titanium powder undergoes oxidation to form TiO2 during sintering. However, under annealing in a reducing atmosphere, oxidation reactions further deplete the lattice oxygen, leading to an increased generation of oxygen vacancies and enhanced carrier concentration, ultimately leading to successful resistivity reduction. The samples consistently exhibit low thermal conductivity values below 2.0 W m−1 K−1 due to crystal defects, complex structure, and phonon scattering at the grain boundaries. The sample doped with 5 wt. %. Ti exhibits the lowest resistivity and highest PF value (409.3 μW/m K2 at 1073 K). Consequently, the figure of merit of Sr0.7Ba0.3Nb2O6−δ with 5 wt. % Ti attains its maximum value of 0.30 at 1073 K, representing a 50% increase compared to that of the undoped sample Sr0.7Ba0.3Nb2O6−δ (0.20 at 1073 K). [ABSTRACT FROM AUTHOR]

With increasing awareness of the circular economy, utilizing waste materials from titanium alloys for polymer composites offers numerous advantages. In this study, medical‐grade titanium alloy, Ti6Al4V chips were finely ground and mixed with epoxy resin to produce particulate‐reinforced composites. The tensile strength showed a 32% improvement compared to the neat epoxy. Similar results were observed for the flexural test, showing a 36% improvement in the composites. Moreover, a substantial 96% increase in thermal conductivity was observed, significantly expanding the potential application areas for the epoxy‐based composites. These improvements were achieved without the use of superfine nanoparticles or other expensive additives. This underscores the potential of a circular approach in the materials world, offering many new opportunities while promoting sustainability. Highlights: Circular utilization of titanium powders in polymer composites.Demonstrated effectiveness of titanium milling in composite production.Production of low‐cost, affordable composites suitable for diverse applications.Remarkable thermal conductivity values.Attainment of finely tuned mechanical properties. [ABSTRACT FROM AUTHOR]

Based on the conducted experimental studies aimed at studying the morphology and elemental composition of titanium powders for additive machines obtained by electrospark dispersion of metal waste of the OT4 alloy in propyl alcohol, it is shown that the process of rapid crystallization of molten OT4 in a liquid working medium contributes to spherical shaping of the particles containing the main elements of Ti and Al. Spherical titanium powder materials obtained from the titanium alloy OT4waste can be effectively used in additive manufacturing. [ABSTRACT FROM AUTHOR]

Spark plasma sintering (SPS) is a promising method for producing titanium components from powder but a limitation is that high sintering temperatures (>900 °C) are normally required to eliminate porosity. Herein, the SPS of commercially pure titanium powder is reported using both cyclic and constant uniaxial pressure and compare densification, microstructure, and mechanical behavior. The following parameters are varied: sintering temperature, TS, 400 to 900 °C; cyclic and constant pressures, 100 to 500 MPa; with and without an isothermal dwell of 60 min at TS. The mechanical behavior is determined by bend and tensile testing. It is demonstrated that the application of cyclic pressure (cyclic‐SPS) gives superior densification over the range of parameters investigated compared with a constant pressure. Bend testing reveals improved ductility after cyclic‐SPS compared with a constant pressure. The dwell at TS further improves mechanical properties, giving excellent tensile ductility and strength. Consequently, at the ultralow temperature of 500 °C, nearly fully dense, ductile, titanium is achieved. It is shown that cyclic pressure enhances the degree of powder compaction at room temperature, and mechanisms are proposed to rationalize the effect of cyclic‐SPS on enhancing the rates of densification and sintering as the temperature increases during processing. [ABSTRACT FROM AUTHOR]

Titanium alloys are among the widely used biomedical materials due to their biocompatibility and mechanical performance. It is an indisputable fact that the materials used in this area must be antibacterial. Therefore, in this study, the production of antibacterial Titanium alloys using NanoAg particles for use in biomedical applications was investigated. First, Ti-6Al-4 V titanium alloys were produced by the powder metallurgy method, which includes blending, pressing and sintering processes. Nano silver particles were synthesized by a chemical reduction method using silver nitrate and glucose. The resulting solution was subjected to Ag + ions and glucose determinations, pH and turbidity analysis. Nano Ag application was carried out by two different methods; dipping and coating method. The obtained samples were analyzed by scanning electron microscopy (SEM) and optical microscopy. Additionally, as the main purpose of this study, antibacterial analysis against Escherichia Coli and Staphylococcus Aureus was performed by percentage reduction test. While the coating method was seen to be more successful in antibacterial tests, the overall Nano Ag application performance was found to be higher against Escherichia Coli bacteria. Being that the sample containing 5% Nano Ag titanium alloys produced with the coating technique showed 100% killing effect against both Staphylococcus aureus and Escherichia coli. [ABSTRACT FROM AUTHOR]

Metal powder contributes to the environmental burdens of additive manufacturing (AM) substantially. Current life cycle assessments (LCAs) of metal powders present considerable variations of lifecycle environmental inventory due to process divergence, spatial heterogeneity, or temporal fluctuation. Most importantly, the amounts of LCA studies on metal powder are limited and primarily confined to partial material types. To this end, based on the data surveyed from a metal powder supplier, this study conducted an LCA of titanium and nickel alloy produced by electrode-inducted and vacuum-inducted melting gas atomization, respectively. Given that energy consumption dominates the environmental burden of powder production and is influenced by metal materials' physical properties, we proposed a Bayesian stochastic Kriging model to estimate the energy consumption during the gas atomization process. This model considered the inherent uncertainties of training data and adaptively updated the parameters of interest when new environmental data on gas atomization were available. With the predicted energy use information of specific powder, the corresponding lifecycle environmental impacts can be further autonomously estimated in conjunction with the other surveyed powder production stages. Results indicated the environmental impact of titanium alloy powder is slightly higher than that of nickel alloy powder and their lifecycle carbon emissions are around 20 kg CO2 equivalency. The proposed Bayesian stochastic Kriging model showed more accurate predictions of energy consumption compared with conventional Kriging and stochastic Kriging models. This study enables data imputation of energy consumption during gas atomization given the physical properties and producing technique of powder materials. [ABSTRACT FROM AUTHOR]

The impact of selective laser melting (SLM) process parameters on the porosity, microstructure, phase and chemical composition, texture, and physical-mechanical properties of orthorhombic titanium aluminide Ti2AlNb (O-alloy) powder was studied using a range of methods, including hydrostatic weighing, scanning and transmission electron microscopy, X‑ray diffraction analysis, energy-dispersive X‑ray spectroscopy, microindentation, and compression testing. It was demonstrated that an increase in the volumetric energy density within the range of 28 to 139 J/mm3 led to the following effects: 1) increase in the relative density of the obtained O‑alloy from 97 to 99.9%, 2) intensification of axial texture with a pronounced 001 direction in the detected β/B2-solid solution, and 3) reduction in the Al content, increase in the Nb content, and lower enrichment with oxygen in the obtained samples. It was demonstrated that detachment from the build platform and longitudinal cutting of the O‑alloy results in the imbalance of residual stresses in samples synthesized on a platform, pre-heated at 200 °C, which is accompanied by the formation of cracks. This study considers the typical structural defects of the alloy, including pores, lack of fusion, and chemical heterogeneity, which are observed following SLM. A series of physical-mechanical properties of the synthesized O‑alloy samples were determined, including Vickers hardness (390–430 HV), elastic modulus (91–98 GPa), compressive yield strength (1060–1080 MPa), and compressive strain (of at least 30%). The relationship between these properties and the structural-textural state of the obtained O‑alloy samples is discussed. [ABSTRACT FROM AUTHOR]

In this paper, titanium‐aluminum based alloy was successfully prepared by introducing titanium powders using powder metallurgy. The experimental results indicated that the microstructures of alloys were composed of the new trititanium‐aluminium layers skeleton and the γ+α2 phases filler, which exhibited excellent compression properties. The compressive strength of the titanium‐aluminum based alloy (10 wt.% titanium) were 509.9 MPa, higher than monolithic Ti‐48Al‐2Cr‐2Nb alloy at 800 °C and 1×10−4 s−1. The deformation mechanism is mainly referred to the motion and rotation of γ+α2 areas and dynamic recrystallization. The γ+α2 areas were surrounded by complete new trititanium‐aluminium layers, which is beneficial to dislocation pile‐up, cross and tangle at grain boundaries, resulting in high strength. Besides, the dislocation pile of γ, α2 phase, and twins in γ phases, are the deformation mechanism in alloys. [ABSTRACT FROM AUTHOR]

Submicron and nanosized powders have gained significant attention in recent decades due to their broad applicability in various fields. This work focuses on ultrasonic spray pyrolysis, an efficient and flexible method that employs an aerosol process to synthesize titanium-based nanoparticles by transforming titanium oxy-sulfate. Various parameters are monitored to better optimize the process and obtain better results. Taking that into account, the influence of temperature on the transformation of titanium oxy-sulfate was monitored between 700 and 1000 °C. In addition to the temperature, the concentration of the starting solution was also changed, and the flow of hydrogen and argon was studied. The obtained titanium-based powders had spherical morphology with different particle sizes, from nanometer to submicron, depending on the influence of reaction parameters. The control of the oxygen content during synthesis is significant in determining the structure of the final powder. [ABSTRACT FROM AUTHOR]

Background: Titanium dioxide (TiO2), a white powder, represents the opacifier used in many products, including drugs, foods, cosmetics, paints, and dyes. Method: The Uv‐Vis spectrophotometry was a particularly suitable technique to quantify TiO2 in the solutions obtained from cosmetics. In this work, we determined the TiO2 content in a total of 88 samples of eye shadows and face powders of different brands and costs. Before to analyse the samples, we developed the mineralization and analysis method, in fact, fusion with potassium bisulphate would be very laborious because it must be carried out on one sample at a time and requires very long times, instead, the mineralization with the acid mixture and the aid of microwaves allowed us to solubilize six samples at the same time within 45 min. Results: From the results obtained, we can state that the highest concentrations of TiO2 are found in the eyeshadows with a maximum value of 36% in a blue eyeshadow. [ABSTRACT FROM AUTHOR]

In this study, titanium (Ti) alloy with carbon (C) solid solution was fabricated by laser powder bed fusion (LPBF) from Ti-TiC mixture powder to investigate the effect of C solid solution on microstructure and tensile properties of LPBF Ti alloy. XRD and TEM analysis showed that part of TiC particles was decomposed from the surface during melting process of LPBF and C was solid soluted in α-Ti for Ti-(0.09~0.4 wt%) C. The solid solution of carbon changed the microstructure of the LPBF Ti alloy to fine acicular microstructure due to the martensitic phase transformation. This was also observed in Ti-0.4 wt% C, where solid solution of carbon was not confirmed, suggesting that in Ti-0.4 wt% C, C was once solid solution and precipitated as TiC after phase transformation. LPBF Ti-C alloys showed good strength-ductility, UTS and elongation at break for Ti-0.2 wt% C were 746 MPa and 26.3%, respectively. [ABSTRACT FROM AUTHOR]

In this study, Ti-Zr-Sc sintered alloys with excellent biocompatibility were fabricated from the elemental mixture of pure Ti, ZrH2 and ScH2 powders, and their microstructures and mechanical properties were investigated to clarify the strengthening mechanism. In particular, the effect of scandium (Sc) used as the third alloying element on the strengthening behavior by grain refinement, oxygen (O) and Sc solid solution, and Sc2O3 particle dispersion was quantitatively evaluated by using the theoretical strengthening models. 0.2% YS of Ti-Zr-Sc alloys decreased with Sc content in the range of 0~1.0 at.% Sc, and increased in the range of 1.0~2.5 at.% Sc. In the former, the added Sc elements reacted with O solutes to form Sc2O3 particles and resulted in a significant decrease of O solid solution strengthening effect. On the other hand, when Sc content was over 1.0 at.%, the strengthening effects by both Sc solid solution and Sc2O3 dispersion were effective, and cause a remarkable increment of 0.2% YS of Ti-Zr-Sc sintered alloys. [ABSTRACT FROM AUTHOR]

Highly porous titanium foams are great candidates for replacing bone structures with a low elastic modulus owing to their ability to avoid the stress shielding effect. However, the production of highly porous foams (>70 vol.%) with well-distributed, stable, and predictable porous architectures using powder compaction and space holders is challenging. In this study, pure titanium powder and mechanically alloyed Ti-13Ta-6Sn were mixed with 50, 70, and 80 vol.% KCl powders as a space holder, cold-compacted, and sintered in a plasma-assisted sintering reactor to produce highly porous foams. The space holder was completely removed using heat and plasma species collisions prior to sintering. A Ti-13Ta-6Sn alloy powder with α, β, and metastable FCC-γ phases was synthesized. The characteristics of the alloyed powder, mixing step, and the resulting sintered samples were compared to those of CP-Ti. After sintering, the alloy exhibited α and β phases and a reduced elastic modulus. Foams with an elastic modulus in the range of the cortical and trabecular bones were obtained. The results showed the effects of the space holder volume fractions on the volume fraction, size, distribution, interconnectivity, and shape of the pores. The Ti-13Ta-6Sn foams exhibited a uniform open-celled porous architecture, lower elastic modulus, higher yield strength, and higher passivation resistance than CP-Ti. Ti-13Ta-6Sn exhibited a nontoxic effect for the mouse fibroblast cell line. [ABSTRACT FROM AUTHOR]

Various systems of biocompatible alloys (mainly based on Ti – Nb and Ti – Ta systems), used for medical purposes, were considered. The specifics of the production of such alloys by selective laser melting have been analyzed. The potential of future use of additive technologies for the creation of high-quality, safe material using β-titanium powder alloys for medical products with enhanced performance characteristics is discussed. [ABSTRACT FROM AUTHOR]

The structure and phase composition of powder materials of the Ti–Al–B system formed in the process of vacuum sintering and synthesis in the mode of high temperature self-propagating synthesis (SHS) are considered depending on the combination of components in the form of elementary powders (Ti, Al and B) and using the finished titanium diboride (TiB2) compound. The proportions of the components were calculated in such a way that the number of interacting elements was sufficient to form a two-phase TiAl3 + TiB2 composition. When sintering the Ti + Al + TiB2 mixture, the diboride is retained, but the presence of TiB is noted as a result of the redistribution of boron due to its migration into free titanium. It was discovered that sintering of compacts from the mixture based on elemental powders (Ti, Al and B) occurs under conditions of high exothermic effect, as a result of which the samples were destroyed. This made it possible to use this mixture under conditions of high-temperature synthesis in combustion mode. As a result of both vacuum sintering and SHS compacting, aluminide TiAl3 and titanium diboride (TiB2) are mainly formed from a mixture of elemental powders (Ti, Al and B). In this case, some transition phases can be observed. It is shown that after the synthesis of the Ti + Al + B mixture, it is possible to obtain a powder product from which compacts are well sintered while maintaining their shape with a slight shrinkage. [ABSTRACT FROM AUTHOR]

The Hot Isostatic Pressing (HIP) process is based on the combined action of high levels of pressure and temperature. In general, such a process is used for reducing or eliminating microporosities in the component, especially when it is produced by additive manufacturing (AM) or casting. In the present work HIP is used for compacting TI6Al4V-ELI powders by means of a pressurized Argon gas acting at high temperature on a sealed can under vacuum in which Argon is previously inflated; thus, a subsequent Solid-State Foaming (SSF) heat treatment allows to produce a Titanium foam without any melting by exploiting gas entrapment. Samples extracted from billets produced setting different HIP parameters (size of Titanium particles and pressures) have been investigated in this work by means of heat treatments in furnace for the SSF: the temperature was kept constant (1020 °C), but the duration was varied in the range 1 - 6 h; the samples were finally analysed by Light Microscopy. Finally, the Response Surface Method (RSM) was used to determine the conditions able to increase both the size and the percentage area of the pores in order to fully control both the involved processes (HIP and SSF). Experimental results revealed that the porosity determined by the SSF is strongly affected by HIP parameters and by the SSF duration: the highest dimension of Ti particles and the highest level of Argon pressure determined the largest values of porosity, in terms of both percentage and pore dimension. The investigated process for producing porous titanium structures can be properly and efficiently combined with manufacturing processes able to create highly customised parts, not only in terms of geometry but also in terms of porosity. [ABSTRACT FROM AUTHOR]

Additive manufacturing is a promising and actively developing method for the synthesis of metal products. The development of techniques for the production of spherical powder particles with specified properties from metals and alloys represents a significant challenge in the field of additive manufacturing. A new method for the production of titanium powders with spherical particles has been proposed, including the method of hydrogenation and dehydrogenation with subsequent spheroidization in thermal plasma. Titanium sponge, used as a feedstock, was saturated with hydrogen using the energy-efficient self-propagating high-temperature synthesis (SHS) method. The resulting hydride was then mechanically ground and then dehydrogenated by thermal decomposition in a vacuum furnace. The resulting precursor was subjected to plasma treatment, which resulted in a product (titanium powder) with a high degree of spheroidization. The physical, chemical, and technological parameters of the titanium powders were investigated. It was found that the final product, spherical titanium powder, has the necessary properties for use in additive manufacturing technologies. [ABSTRACT FROM AUTHOR]

Diamond-like carbon (DLC) films on titanium alloy Ti6Al4V substrates were tested with nanoindentation and surface roughness to look at the hardness and roughness of the coating and substrate systems as well as their mechanical properties. The powdered titanium alloy Ti6Al4V used in the substrate specimen was produced using laser powder bed fusion, an additive manufacturing process. In this study, we investigated the influence of substrates on the nanoindentation and surface roughness of the DLC film layer with an estimated 2. 2 1 μ m thickness on Ti6Al4V substrates. The findings of the nanoindentation show that the reaction to the impact was more flexible than expected. Maximum load, residual nanoindentation depth, hardness, and modulus may influence mechanical properties. The DLC-film Ti6Al4V substrate materials' top surface roughness is measured. As a result of the increased load-carrying ability of DLC/Ti6Al4V, Ti6Al4V is a superior choice for substrate materials for DLC films, A DLC coating, measuring 2. 2 1 μ m in thickness, was applied to a Ti6Al4V substrate utilizing a 5-min chromium deposition process. The biocompatibility of the substrates plays a crucial role in determining the DLC films capacity to prolong the lifespan of bone implants. [ABSTRACT FROM AUTHOR]

High‐activity TiB2 submicron powders were synthesized via microwave‐assisted carbothermal reduction, and their oxidation behavior at 550°C–1000°C for 0.5–1.5 h in air atmosphere was carried out by the isothermal oxidation test. The phase composition and microstructure evolution of the oxidation products were performed by X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). It was established that TiB2 submicron powders had been significantly oxidized at 550°C, and the oxidation products were TiO2 and B2O3. Hexagonal plate‐like TiB2 grains had been completely disappeared, and fragmented into uniform nano‐scale spherical TiO2 particles after being oxidized at 1000°C for 1 h, accompanied by the violent evaporation of B2O3 products at temperatures above 1000°C. In addition, the corresponding oxidation kinetics was investigated by using a non‐isothermal thermogravimetric (TG)–differential scanning calorimetry (DSC) technique. The results showed that the Mample power law (n = 1) was the most probable mechanism function, and the oxidation activation energy E of TiB2 submicron powders was 640.58 kJ/mol. [ABSTRACT FROM AUTHOR]

Semi-empirical quantum models such as Density Functional Tight Binding (DFTB) are attractive methods for obtaining quantum simulation data at longer time and length scales than possible with standard approaches. However, application of these models can require lengthy effort due to the lack of a systematic approach for their development. In this work, we discuss the use of the Chebyshev Interaction Model for Efficient Simulation (ChIMES) to create rapidly parameterized DFTB models, which exhibit strong transferability due to the inclusion of many-body interactions that might otherwise be inaccurate. We apply our modeling approach to silicon polymorphs and review previous work on titanium hydride. We also review the creation of a general purpose DFTB/ChIMES model for organic molecules and compounds that approaches hybrid functional and coupled cluster accuracy with two orders of magnitude fewer parameters than similar neural network approaches. In all cases, DFTB/ChIMES yields similar accuracy to the underlying quantum method with orders of magnitude improvement in computational cost. Our developments provide a way to create computationally efficient and highly accurate simulations over varying extreme thermodynamic conditions, where physical and chemical properties can be difficult to interrogate directly, and there is historically a significant reliance on theoretical approaches for interpretation and validation of experimental results. [ABSTRACT FROM AUTHOR]

With the increase in train speed and axle weight, the quality and service life of the rail (U71Mn steel) are more demanding. Aiming at the excellent properties of nickel/nickel-based alloys and ceramic materials, this paper prepares TiC/Ni45 composite coatings for rail repair by in-situ synthesis of ceramic phases using laser cladding technology. The effects of in-situ synthesized TiC on the physical phase, microstructure, microhardness and wear resistance were investigated and discussed in detail. The results show that the reaction of in-situ synthesized TiC can proceed positively, and the microstructure of the cladding layer mainly consists of the segregation of Cr, TiC particles, and substrate phase. With the increase of nickel-coated graphite and titanium powder, the average microhardness value of the cladding layer increased, and the average friction coefficient and wear volume decreased. When the mass fraction of (Ti + C) reaches 15 wt%, the average friction coefficient of the cladding layer reaches the minimum value. When the mass fraction reaches 20 wt%, the average microhardness of the cladding layer reaches 2.65 times that of the substrate, and the wear mechanism is transformed from mainly adhesive wear to abrasive, oxidative, and fatigue wear. [ABSTRACT FROM AUTHOR]

Powdered titanium dioxide (TiO 2) photocatalysts are widely used in the photodecomposition of water for H 2 production due to their low cost, and high stabilizing activity under UV light. However, it has encountered great challenges in photocatalytic reactions, such as easy aggregation and being difficult to recycle. To solve these problems, we proposed a hydrogel (HY) composite material. The material Au@TiO 2 /HY was created by mixing HY with TiO 2 supported co-catalyst Au nanoparticles (NPs). The results show that Au@TiO 2 /HY is difficult to spread owing to its block shape in the photocatalytic reaction, the H 2 evolution rate is only 4.59 mmol/g/h. Therefore, on account of the fact that hydrogel microspheres (HYM) can enhance performance, Au@TiO 2 /HYM was self-assembled by mechanical methods on the synthesis scheme of Au@TiO 2 /HY, which improves the Ultraviolet and visible (UV–vis) light absorption range. The H 2 evolution rate of Au@TiO 2 /HYM is 17.08 mmol/g/h, which is ∼3.7-fold higher than that of Au@TiO 2 /HY (4.59 mmol/g/h), according to the data. The mechanism studies demonstrate that the HYM improve the UV–vis light absorption range and promote the separation of photogenerated electron-hole pairs in Au@TiO 2 /HYM during photocatalysis compared to typical bulk HY, thus improving the photocatalytic H 2 evolution activity. The results provide a reference for the preparation of recyclable HYM for photocatalytic H 2 production. [Display omitted] • An innovative self-assembled hydrogel microsphere photocatalyst was designed. • High light utilization, efficient solar-to-hydrogen conversion and easy to recycle. • The excellent performance was attributed to the increased the absorption range of UV–visible light, and the catalytic mechanism was discussed and proposed. [ABSTRACT FROM AUTHOR]

Using the method of hot compaction (HC) of mechanically activated powder mixtures of titanium and carbon (carbon black) in an ethanol medium, titanium-matrix composites with a carbide strengthening phase were obtained. To obtain a composite with different content of titanium carbide, the amount of carbon was varied within the range of 0–1 wt.%. The mechanically activated carbon-doped titanium powder mixtures, as well as the mechanically activated titanium powder subjected to HC (temperature of 900°C and holding time of 15 min) and additional annealing at different temperatures and holding times are studied by optical metallography, scanning electron microscopy, and X-ray diffraction and chemical analysis. According to the metallography and X-ray diffraction results, the TiC content in the HC composite has been found to be significantly higher than the estimated value. The reason is a destruction of ethanol molecules during mechanical activation resulting in the release of carbon and hydrogen. To obtain the targeted (no more than 10 vol.%) TiC content in the titanium matrix composite, it is necessary to establish a specific technological mode for the mechanical activation of the titanium powder. [ABSTRACT FROM AUTHOR]

Glass lubricant with a suitable viscosity is essential for producing high‐quality titanium products by the hot extrusion process. In this study, a novel lubricant of B2O3–SiO2–Al2O3–Na2O–TiO2 (BSANT) glass was proposed, where the effects of B2O3/SiO2 molar ratio (B/Si) and B2O3 content on viscosity and structure were investigated. The results showed that the BSANT glass viscosity was gradually decreased, and the viscous activation energy was decreased by 20.24% with an increased B/Si ratio from 0.415 to 0.719. This was attributed to the decreased amounts of Q3, [BO4], [AlO4], and bridging oxygen (BO) in the network structure, which in turn resulted in a decreased network degree of polymerization. When B2O3 content was increased from 18.70 to 33.12 mol.%, the melt viscosity value at 950 ℃ was decreased by 64.51%, and the viscous activation energy was reduced by 15.82%. Boron anomalies were also observed in glass melts with the B2O3 content from 28.28 to 33.12 mol.%. The mechanisms responsible for this phenomenon were thoroughly discussed in the study. Additionally, a comparison and discussion of the applications of glass lubricants in metal hot working were presented. A glass lubricant with a specific composition was recommended for use in hot extrusion process within the temperature range of 950–1100°C due to its relatively stable viscosity properties. A novel lubricant of B2O3–SiO2–Al2O3–Na2O–TiO2 (BSANT) glass was proposed, where the effects of B2O3/SiO2 molar ratio (B/Si) and B2O3 content on viscosity and structure were investigated. A glass lubricant with a specific composition was recommended for use in hot extrusion process within the temperature range of 950–1100°C due to its relatively stable viscosity properties. [ABSTRACT FROM AUTHOR]

In the realm of additive manufacturing, powder bed fusion (PBF) is recognized as an innovative and highly effective technique for manufacturing titanium-based materials. With an understanding of and regulation for the complex microstructural evolution that occurs during the PBF process, several previous studies have been conducted to enhance the reliability, efficiency, and performance of the PBF through investigation and optimization of microstructure evolution in PBF. These studies have examined various aspects, including feedstock materials, process parameters, and post-processing techniques, in order to gain a comprehensive understanding and control over the progression of microstructure in the PBF. Process parameters are widely acknowledged as critical determinants in the PBF process for titanium-based materials, significantly influencing the quality in 3D printed components. Previous studies have provided an in-depth discussion of the effects of process parameters, such as laser power, scanning speed, and hatching space, on the microstructure evolution of Ti-based materials. The primary objective of this review paper is, therefore, to provide a comprehensive and clear explanation of recent efforts, with a particular focus on investigating the complex evolution of microstructures in Ti-based materials during the PBF process. This thorough discussion is devoted to providing a comprehensive understanding of the effects of process parameters on the evolution of microstructures in Ti-based materials. [ABSTRACT FROM AUTHOR]

Suboxidized titanium, as a promising anode for electrocatalytic oxidation reactions in wastewater treatment, presents a viable pathway to solve the challenging water pollution. However, current suboxidized titanium anodes are primarily fabricated hot pressing of by suboxidized titanium powders, further hampering their application in wastewater treatment due to high costs and complex shaping processes. To overcome these limitations, this work employs the plasma electrolytic oxidation (PEO) technology to in-situ fabricate porous TiO 2 coating precursors on commercial pure titanium substrates, followed by an annealing process to carefully reduce the TiO 2 coatings with hydrogen gas, and finally achieving the cost-effective production of high-purity Magnéli phase Ti 4 O 7 -coated electrode. The obtained Ti 4 O 7 -coated electrodes exhibit a highly ordered granular structure, good crystallinity, wide electrochemical window, and low interfacial charge transfer resistance. Importantly, the Ti 4 O 7 -coated electrodes also offer a simple fabrication process, lower energy consumption, and reduced costs compared to advanced boron-doped diamond (BDD) and bulk Ti 4 O 7 electrode. The electrochemical oxidation tests also demonstrate that Ti 4 O 7 -coated electrodes can achieve the complete degradation of 100 mg/L phenol within 240 minutes, exhibiting excellent catalytic activity and potential applications in wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Titanium is a metal with excellent physical and chemical properties. Although it is highly abundant in the earth's crust, the difficulty of its extraction makes it expensive and restrict its application on a large scale. It has become a world problem to develop a titanium smelting method with low cost and short process. In this research, TiH1.924 powder with a low oxygen content was produced by hydrogen-assisted magnesiothermic reduction at 650 °C for 2 hours. By optimizing the thermodynamic calculation method of Ti–O–H solid solution, the thermodynamic data of Ti–O, Ti–H, and Ti–O–H with different oxygen contents have been calculated. The results showed that the hydrogen in Ti–O–H has destabilizing effect on the oxygen in Ti–O lattice. Therefore, under hydrogen atmosphere, Mg can break the thermodynamic limit of deoxidation of Ti–O solid solution, obtaining a low oxygen content reduction product. In order to further reduce the oxygen content in the product, the mechanism of secondary oxidation of the titanium hydride product was investigated, leading to the conclusion that higher hydrogen content in titanium hydride can obviously enhance its anti-oxidation property. The research can provide theoretical support for the deep reduction of TiO2 using low-cost Mg powder to obtain titanium powder with a low oxygen content. [ABSTRACT FROM AUTHOR]

Mandibular reconstructive surgery is necessary for large bone defects. Although various reconstruction methods have been performed clinically, there is no mandibular reconstruction method that meets both sufficient strength criteria and the patient's specific morphology. In this study, the material strength of the cylindrical lattice structures formed by electron-beam melting additive manufacturing using titanium alloy powder was investigated for mandibular reconstruction. The virtual strengths of 28 lattice structures were compared using numerical material tests with finite element method software. Subsequently, to compare the material properties of the selected structures from the preliminary tests, compression test, static bending test and fatigue test were conducted. The results showed that there were correlations with relative density and significant differences among the various structures when comparing internal stress with deformation, although there was a possibility of localized stress concentration and non-uniform stress distribution based on the lattice structure characteristics. These results suggest that the lattice structure of body diagonals with nodes and a cell size of 3.0 mm is a potential candidate for metallic artificial mandibles in mandibular reconstruction surgery. [ABSTRACT FROM AUTHOR]

The versatility of titanium (Ti) allows it to be employed in various industries, from aerospace engineering to medical technology, highlighting its significance in modern manufacturing and engineering processes. Spark plasma sintering (SPS) is currently being explored to enhance its properties further and broaden its application range. The current study focuses on exploring and optimizing the effect of SPS temperature (800, 900, 1000, 1100, 1200, and 1400 °C) on pure Ti sintered at 60 MPa in a controlled argon environment with a dwell time of 5 min. All the prepared samples were highly dense with a relative density above 99%, but exhibited significant variations in grain size (10 to 57 µm), tensile yield strength (488 to 700 MPa), ultimate tensile strength (597 to 792 MPa), and ductility (4 to 7%). A microstructural investigation was performed using XRD, SEM, and EDS to predict the influence of sintering temperature on the formation of different phases. The XRD patterns of all sintered samples showed the presence of single-phase α-Ti with hexagonally close-packed Ti. This work is a step forward in optimizing SPS-processed Ti's physical and mechanical properties for enhanced structural and biomedical applications. [ABSTRACT FROM AUTHOR]

In this review, composite studies using titanium and graphene additions to alumina as matrix materials are summarized. In the light of studies conducted in recent years, the importance of graphene reinforcement and the effects of titanium reinforcement on the properties of ceramic matrix composites have been stated. Alumina matrix composites, which are the most widely used ceramic matrix composites, have been used in the industry from past to present due to their properties such as low density, high hardness and chemical stability. However, the low fracture toughness of alumina (3.5 MPa. m1/2) limits its usage area, therefore, the existing mechanical properties are improved with second phase additions, and higher hardness and fracture toughness are obtained with the reinforcements. Although it has been stated in the reviewed studies that titanium reinforcement into alumina matrix generally results in lower hardness, fracture toughness and bending strength compared to monolithic alumina and that titanium reinforcement is an important step in improving the properties of alumina with low fracture toughness, some studies have shown that titanium addition has increased fracture toughness (4,32 MPa.m1/2) and has been reported to increase bending strength. Studies have shown that a second reinforcement material is added to the Al2O3-Ti composite in order to improve the mechanical properties obtained by reinforcing titanium into alumina matrix. It has been observed that literature studies on the addition of graphene to the Al2O3-Ti structure are limited. In a limited study, results were obtained that graphene reinforcement reduced porosity and increased conductivity, wear resistance, hardness and fracture toughness (8.7 MPa.m1/2) compared to monolithic alumina and other reinforcements. These data show that the use of graphene supplements will continue to increase. In this review, the addition of titanium and graphene powders to the alumina matrix, production methods by powder metallurgy method, and the effects of the reinforcements on microstructure and mechanical properties were examined. [ABSTRACT FROM AUTHOR]

Electrode-induction gas atomization (EIGA) is a promising and cost-effective method for producing spherical intermetallic titanium powders used in additive manufacturing. The present study investigates the morphology, microstructure, chemical and phase compositions, nanoindentation properties of a commercial pre-alloyed TiAl-based EIGA alloy powder. The Ti – 48Al – 2Cr – 2Nb powder is characterized by a spherical shape and dendritic structure with the dendrites enriched with Nb and the interdendritic areas enriched with aluminum and chromium. The temperature ranges of the phase transformations in the powder with precipitation/dissolution of phases α2 , α, γ, B2, (TiNb)Cr2 are determined using thermal analysis during heating and cooling in an inert atmosphere of argon at a rate of 50 K/min. Development of an oxidation process at the temperatures above 500°C and significant increase in its rate at the temperatures above 900°C is detected. [ABSTRACT FROM AUTHOR]

MXenes, a large family of two‐dimensional carbides and/or nitrides, are among the most studied materials worldwide due to their great diversity of structures and compositions. Their unique properties find use in several applications. Typically, they are manufactured by selective wet‐chemical etching of layered MAX phase ceramics, which are produced nowadays primarily for MXene synthesis. However, the synthesis of MAX phases has not been changed since the time of their use in structural and high‐temperature applications, and it has not been optimized for MXene manufacturing. The main purpose of this study is to develop a porous Ti3AlC2 MAX phase that can be easily ground into individual grains without time‐consuming, harsh, and tedious crushing and milling steps. Moreover, we also demonstrate the synthesis of highly porous Ti3AlC2 from an inexpensive titanium sponge instead of a highly pure titanium powder and explain the mechanisms of reaction sintering and formation of porous MAX phase. MXene obtained from this MAX phase, Ti3C2Tx, shows larger flake size and higher electrical conductivity in thin films, compared to the materials produced from the costly fine titanium powder. The proposed approach may apply to the synthesis of other MAX phases as well. [ABSTRACT FROM AUTHOR]

The complex structure of Ti/HA (HA: hydroxyapatite) implants prepared by additive manufacturing technology plays an essential role in its application in bone repair. Digital light processing (DLP) is widely used to prepare bioceramics with complex structures. However, it is a challenge to prepare Ti/HA biomaterials by DLP due to the high ultraviolet (UV) absorption of Ti powder. In the present work, TiH2 powder coated with a TiO2 layer is selected to reduce the UV absorption and improve the curing depth for DLP printed green bodies of TiO2@TiH2/HA, because the TiO2@TiH2 powder can be reduced by 12.7% compared to the TiH2 powder without any oxidation. Then, the shell layer of TiO2 undergoes dehydrogenation and reduction reaction with the core phase of TiH2 during the sintering process to transfer TiO2@TiH2/HA into TixOy@Ti/HA. In addition, the effects of HA content on compressive strength and biocompatibility are investigated in the TixOy@Ti/HA biomaterials. The results show that when adding 60 vol%HA, the maximum monolayer curing depth of the slurry reaches 90.1 ± 3.5 µm. 40%TixOy@Ti/60%HA shows the maximum effect in promoting the pre‐osteoblast differentiation and a relatively high compressive strength of 48.7 ± 3.5 MPa. This work provides an experimental basis for the preparation of ceramic–metal composites with high UV absorptivity using DLP. [ABSTRACT FROM AUTHOR]

NH3 is a dangerous gas, posing significant threats to human health and the delicate equilibrium of the environment. It emerges as a primary contributor to the noxious gas emissions prevalent in the selective catalytic reduction (SCR) processes employed by marine diesel engines. Its deleterious impact extends beyond the immediate surroundings, permeating the air with potential health hazards and exacerbating environmental degradation. The repercussions of NH3 emissions are far-reaching, impacting respiratory health, ecosystem vitality, and overall air quality. In this paper, BaTiO3/Ti3C2Tx composites were synthesized by anchoring BaTiO3 nanospheres on multilayer Ti3C2Tx nanosheets. The shortcomings of low sensitivity and poor recovery of the pristine Ti3C2Tx MXene gas sensor were improved. The BaTiO3/MXene composite sensor exhibits an improved response (10.43) to 20 ppm NH3 at room temperature, which is about 3.5 times higher than that of the pure MXene sensor. Furthermore, the BaTiO3/MXene composite sensor greatly improves the recovery time and exhibits outstanding repeatability, stability, and high selectivity to NH3. The exceptional characteristics of these composites underscore the potential for advancing novel sensitive materials in the form of BaTiO3/MXene composites, specifically tailored for high-performance NH3 sensors. [ABSTRACT FROM AUTHOR]

This study explored synthesizing titanium carbide (TiC) from bitumen coke using mechanical alloying. Initially, raw bitumen coke (5.9 wt.% sulphur) from delayed coking was desulphurized to produce low sulphur coke with a sulphur content of 0.2 wt.% for comparison purposes. Both high and low sulphur coke samples were mechanically alloyed with titanium (Ti) powder in a planetary ball mill under various conditions (milling time, milling speed, and ball‐to‐material ratios [BMR]). TiC was successfully produced from both high sulphur and low sulphur coke samples. The formation of TiC was confirmed by X‐ray diffraction (XRD) analysis. The effects of the experimental parameters on the production of TiC were evaluated. The experimental results showed that the high sulphur coke and Ti were converted into TiC after 10 h milling, whereas the low sulphur coke and Ti were converted into TiC much faster (after 5 h milling) at the same milling speed and BMR. Under the same milling time and BMR, the high sulphur coke and Ti were converted into TiC at 400 rpm, whereas the low sulphur coke and Ti were converted into TiC at 300 rpm. In addition, the high sulphur coke and Ti were converted into TiC when the BMR was 60:1, and the low sulphur coke and Ti were converted into TiC when the BMR was 40:1 under the same milling time and speed. Overall, preliminary results suggest that the conversion of low sulphur coke samples is easier and requires less energy to produce TiC compared to the high sulphur coke samples. [ABSTRACT FROM AUTHOR]

The advancement in additive manufacturing has significantly expanded the use of lattice structures in many engineering fields. Titanium diamond lattice structures, produced by a direct metal laser sintering process, were experimentally investigated. Two cell sizes were selected at five different relative densities. Morphological analysis was conducted by digital microscopy. The compressive tests and digital image correlation technique allowed the evaluation of elastic moduli to be used in the Gibson–Ashby model. Failure mechanisms of the structures have been analysed by digital image correlation, which represents a promising technique for strain evaluation of such structures. A non-linear finite element model of the lattice structures was developed and validated using the experimental data. The analysis of the results highlights the good mechanical properties of the Ti6Al4V alloy lattice structures. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop an approach for incorporating titanium oxide or titania into oil palm leaves ash (OPLA) using a simple procedure. The study process comprised the mixing of oil palm leaves (OPL) powder and titanium tetraisopropoxide in chloroform solvent, followed by the elimination of the solvent to obtain a solid residue. Subsequently, the residue obtained was calcined at 500 °C for 5 hours, leading to the production of a yellow-light powder. The results of product characterization using X-ray diffraction (XRD) and scanning electron microscopy analysis showed the presence of titanium oxide in OPLA. In addition, the wide diffractogram detected in XRD analysis revealed the presence of a silica peak. The un-sharp peaks in the regions of 25.6°, 38.2°, 47.9°, 54.5°, and 62.9° showed that the TiO2 particles were pure anatase, and no peaks of other TiO2-anatase phases were detected. Analysis using SEM showed that the surface of the material obtained was irregular and tended to have a hollow shape, while energy dispersive X-ray analysis revealed a SiO2 content of approximately 73%. However, the titanium element or titania was not detected possibly due to its small concentration. The material obtained also had a good catalytic activity for safranin-O dye elimination under sunlight irradiation, which served as the activation energy source. Based on these findings, the use of OPLA (a side product of oil palm plantations) could be evaluated economically due to its effective role in the catalytic process despite the addition of a small amount of titania catalyst. [ABSTRACT FROM AUTHOR]

The reaction kinetic characteristics of two different particle sizes of titanium powder under different heating rates are studied by the synchronous thermal analysis. The initial reaction temperature, exothermic peak temperature, and the temperature of maximum mass gain rate are analyzed by the thermal analysis curves with different particle sizes and heating rates. Results show that the ignition probability and combustion stability of titanium powder increase with decrease in titanium powder particle size. The activation energy and pre-exponential factor of titanium powder are calculated using the KAS method and the reliability of the calculation results is tested using the Ozawa method. The initial reaction temperature, the exothermic peak temperature, and the maximum mass gain rate temperature increase with the increase in the heat rate for 12.5 μm titanium powder. The average activation energy of 12.5 μm titanium powder is lower than the result of 51.3 μm titanium powder. The most probable mechanism function of titanium powder during the reaction process is obtained using the Coats–Redfern method. [ABSTRACT FROM AUTHOR]

The rapid development of rare-earth fluorescent materials based on the fluorescence intensity ratio method allows the monitoring of internal temperature, stability and service life of thermal barrier coatings (TBCs). In this paper, Eu3+ doped (YSZ) 0.3 -(YTaO 4) 0.7 rare-earth ceramic materials was firstly prepared by chemical co-precipitation technique, and the doping content of Eu3+ was optimized by comparing its effect on morphology, luminescence and temperature sensitive performance of (YSZ) 0.3 -(YTaO 4) 0.7. Then the Ti 3 C 2 T x MXene was subsequently blended into the optimal (YSZ) 0.3 -(YTaO 4) 0.7 : Eu3+ powders by mechanical milling. The influence of Ti 3 C 2 T x MXenes on the structure, morphology, fluorescence properties and temperature sensitivity of (YSZ) 0.3 -(YTaO 4) 0.7 : Eu3+ powders was further investigated systematically. Results showed that (YSZ) 0.3 -(YTaO 4) 0.7 : Eu3+ powders were compound of M′-YTaO 4 and YSZ in tetragonal phase. The optimal doping content of Eu3+ is 1.5 mol%. The adding of Ti 3 C 2 T x MXene did not affect the structure of (YSZ) 0.3 -(YTaO 4) 0.7 :Eu3+ powders. After addition of Ti 3 C 2 T x MXenes, part of (YSZ) 0.3 -(YTaO 4) 0.7 :Eu3+ particles embedded in the middle of the accordion-shaped MXenes sheet, while the other part wrapped around MXenes. Ti 3 C 2 T x MXenes could significantly improve the luminescence intensity, fluorescence lifetime and temperature-sensitive performance of (YSZ) 0.3 -(YTaO 4) 0.7 : Eu3+powders. The optimal addition amount of Ti 3 C 2 T x MXenes is 0.6 wt%. The absolute and relative sensitivities of MXene/(YSZ) 0.3 -(YTaO 4) 0.7 :Eu3+ powders archived 2 times of (YSZ) 0.3 -(YTaO 4) 0.7 : Eu3+ powders. Therefore, MXene/(YSZ) 0.3 -(YTaO 4) 0.7 : Eu3+ could be used as temperature-indicating ceramic materials with highly efficient fluorescent properties for real-time monitoring of internal temperature of TBCs. [ABSTRACT FROM AUTHOR]

The state‐of‐the‐art manufacturing process known as additive manufacturing (AM) employs components that may be processed by AM, including ceramics, polymeric materials, metallic substances, titanium, metallic substances, and composites, to produce parts with intricate designs and exact properties. Fused deposition modeling (FDM) is a rapidly growing 3D printing technique. However, most FDM systems only support polylactic acid (PLA) or acrylonitrile butadiene styrene (ABS) as a printing medium. The impact of print orientations and graphene nanoparticles upon the tensile and shear properties of PLA single‐lap joint samples created by FDM has been investigated in this work. According to experimentation, the 0° orientation has the highest load‐bearing capacity and shear strength compared to 45° and 90°. Also, addition of GNP to epoxy adhesive improved greatly, with 0.25 to 1.00 weight percentages of 20.94, 12.34, 38.98, and 31.11%, respectively. FESEM has been used to analyze the failure criteria. The free vibrational analysis confirmed that the 3DS6 sample had the highest natural frequency (598.7 Hz) compared to all other samples. The artificial neural network (ANN) approach accurately predicted the failure load. The overall R2=0.8471 achieved is below the permissible margin of error, indicating that both the outcomes are reliable and in satisfactory agreement. [ABSTRACT FROM AUTHOR]

Experimental dependences of burning rate of powder and granulated mixtures 5Ti + 3Si, Ti + C , (Ti + C + 20% Cu, (Ti + C + 20% Ni, and Ti + C (with amorphous carbon in the form of soot and crystalline carbon in the form of graphite) on titanium particle size are discussed using different models of combustion front propagation in a condensed medium for the first time. Within the framework of the theory of gasless combustion (with and without account for the mechanism of capillary spreading), microheterogeneous models do not even qualitatively explain the difference in the dependences of the burning rate on the size of titanium particles for powder mixtures of titanium with soot and with graphite or an increase in the burning rate of Ti + C powder mixtures when diluted with nickel and copper, accompanied by a drop in combustion temperature. The restructuring of the medium (granulation of powder mixtures) changes burning rate without changing the phase composition of the synthesis products. Within the framework of the convective–conductive combustion model, all these results are explained uniformly by the inhibitory effect of impurity gases released ahead of the combustion front in powder mixtures with fulfillment of heating conditions of the component particles. The effect of impurity gas release on the burning rate of powder mixtures can be estimated for each composition by the difference in the burning rates of granulated and powder samples. For all the granulated mixtures studied, where the effect of impurity gases on burning rate is leveled, the analytical approximation of the experimental dependence of burning rate on titanium particle size shows qualitative agreement with the dependence that follows from the convective–conductive combustion model. [ABSTRACT FROM AUTHOR]

Electric discharge machining (EDM) is a non-conventional manufacturing process that has several variations, one of which is powder mixed EDM that involves adding small particles to the dielectric. In this present experimental study, titanium powder blended in green dielectric, deionized water with different concentrations has been used for die-sinking EDM of Nimonic C-263. In order to obtain enhanced material removal rate, reduced tool wear rate and lesser surface roughness, relevant input parameters are optimized using TOPSIS. Cylindrical copper rod has been used as the tool electrode and a varying flushing pressure is applied to remove the deposited debris from the machining zone. The optimal parametric values are found to be as follows; pulse-on-time = 4 µs, peak current = 10 A, pulse-off-time = 5 µs, flushing pressure = 1 kg/cm2, and powder concentration = 9 g/lit. SEM micrographs indicate that a better surface finish is achieved by increasing the concentration of the powder in the dielectric at lower values of peak current. [ABSTRACT FROM AUTHOR]

In this research, TiB 2 powder was synthesized using the sol-gel process, resulting in nanometer-scale dimensions. Initially, a sol was prepared in a four-component system consisting of alcohol-dispersant-water-solvent.Various analytical techniques, including DLS, Zetameter, XRD, FTIR, SEM, and DTA/TG, were employed to elucidate the mechanism of product formation in the sol-gel process. Maintaining the pH within the range of 4 led to achieving TiB 2 nanoparticles with precursors containing titanium and boron resources below 10 nm. The results of the viscosity and zeta potential tests showed that the solid particles in the sol are more stable in the pH range of less than 4 and have more favorable conditions to continue the synthesis process. FTIR data indicated the presence of B–Ti and carbon-containing bonds within the 600–1650 cm⁻1 range in the prepared gel powder. DTA analysis revealed that the initial nucleation of TiB 2 particles occurred within the temperature range of 1300 °C. XRD patterns confirmed the formation of the TiB 2 crystalline phase, which further progressed with increasing temperature, reaching up to 1400 °C. Surface analysis of the synthesized particles indicated a specific surface area of approximately 153.42 m2/g, with porous and meso-sized surfaces. Raman results showed the presence of Ti–B in the final product, and XPS graphs also confirmed these bonds. PSA results showed that the particle size distribution is in the range below 50 nm. SEM and TEM microstructural images provided visual evidence of the synthesis of TiB 2 particles smaller than 100 nm, characterized by a narrow and uniform distribution range. [ABSTRACT FROM AUTHOR]

Electron powder bed fusion (EPBF), as one of the common additive manufacturing techniques, has received increasing attention. EPBF-processed Ti-6Al-4V is widely used in biomedical and aerospace industries. However, titanium alloys prepared by EPBF have large pores and poor corrosion resistance. Heat treatment is a simple and non-polluting way to improve material properties. However, the effect of heat treatment on the corrosion resistance of EPBF-processed Ti-6Al-4V alloy has not been thoroughly researched. In this paper, Ti-6Al-4V samples processed by EPBF were treated with different heat treatment methods. All corrosion tests were performed in 3.5 wt.% NaCl solution at ambient temperature. HT800 has the highest content of β phase, and the smallest grain boundary density, and therefore has the best corrosion resistance. The corrosion current of HT800 is reduced from 0.109 µA/cm2 unheated to 0.022 µA/cm2, a reduction of 79.82%. [ABSTRACT FROM AUTHOR]

AISI 4140 steel, known for its strength and wear resistance, is widely used in the oil industry, particularly for drilling equipment. However, its wear resistance varies based on the environment and drilling conditions, necessitating additional surface modifications for optimal performance. This paper investigates the microstructure and wear performance of AISI 4140 steel clad with WC-Ti composite powder using gas tungsten arc welding. Four different WC-Ti powders were used, with the Ti content ranging from 10 wt% to 40 wt%. The welding parameters were kept constant, except for the current intensity which was varied between 100 A and 120 A. The through-thickness micro-hardness profile and wear resistance were evaluated. Examinations revealed that, by increasing the current intensity from 100 A to 120 A, the size of the dendrites in the weld region grew. Simultaneously, mechanical properties such as hardness and wear resistance diminished. It was also found that, with the increase in the titanium content of the composite powder, the size of the dendrites decreased. The micro-hardness results indicated a rise in surface hardness from 250 HV (base metal) to a maximum of 850 HV (cladding). The higher the content of Ti in the composite powder, the greater the hardness and wear resistance of the cladding. [ABSTRACT FROM AUTHOR]

During metal injection molding (MIM), water-soluble polyethylene glycol (PEG) and polymethyl methacrylate (PMMA) binder system usually lead to the formation of a large number of holes. The time spent in injection demolding increases with the size increasing of the parts for the poor thermal conductivity of the binder system. Poly (β-hydroxybutyrate)(PHB) was used as a PEG crystallization inhibitor to solve this problem. The effects of PHB content on the thermal conductivity, crystallization behavior, rheological properties of the binder, injection holding time and microstructure of the green body were studied by thermal conductivity meter, DSC, rheological experiments and fourier transform infrared spectroscopy (FTIR). The results show that in PHB / PEG blends, with the increase of PHB content, the crystallization temperature decreases from 55.18 ℃ (pure PEG) to 51.4 ℃ (25% PHB modified, mass fraction, the same as below). With the increase of PHB content from 0%-25%, the melting enthalpy and thermal conductivity of PEG blends gradually increase from 79.5 J/g to 107.6 J/g and from 0.2433 W·m-1·K-1 to 0.3469 W·m-1·K-1, respectively. The increasing of binder crystallinity leads to the improvement of thermal conductivity. Due to the complex hydrogen bond interaction in the PEG/PHB/PVAc ternary system, the crystallization temperature of the binder decreases from 50.07 ℃ of pure PEG to 43.3 ℃ of PEG with 25% PHB. The relationship between the viscosity and shear rate of the feedstock prepared with 15% PHB modified PEG binder conforms to the law of power-law fluid. And the shear thinning index of the feedstock prepared with 15% PHB modified PEG binder decreases from 0.77 of pure PEG to 0.62 at 120 ℃.Under the same injection conditions, the injection demolding time is significantly shortened from 100 s (unmodified) to 50 s of PEG with 15% PHB. Meanwhile, the injection green body, with smooth surface, few and uniform distribution internal holes can be obtained using 15% PHB modified PEG binder.

This is an article in the field of metallurgical engineering. In this article, TiH2 powder was selected as the experimental raw material to study the sintering behavior of TiH2 powder under different pressing pressure and holding time in cold isostatic pressing, to reveal the effects of pressing pressure and holding time on the shrinkage as well as the relative density of TiH2 sintered specimens, in order to improve the density of the billet and the performance of the products. The results show that the shrinkage of the sintered sample decreases with the increase of the pressing pressure, and when the pressing pressure reaches 400 MPa, the pressing pressure has little effect on the relative density of the sintered sample. For the consideration of the sample preparation efficiency and the pressing pressure limit of the cold isostatic press, the pressing pressure should not exceed 400 Mpa. The shrinkage of sintered samples decreases with the increase of holding time, and when the holding time reaches 20 min, the relative density of sintered samples changes little with the extension of holding time. For the consideration of sample preparation efficiency, the suitable holding time is 15～20 min.