Addition Of Vanadium Research Articles

Effect of small vanadium addition on the microstructure, transformation temperatures, and corrosion behavior of a Cu72Al17Mn11 shape memory alloy

In the present work, effects of 0.1 at.% and 0.2 at.% vanadium content on the microstructure, transformation characteristics and corrosion behavior of the Cu72Al17Mn11 shape memory alloy (SMA) have been investigated by means of OM, SEM, XRD, DSC measurements and corrosion test. The alloys were produced in an induction furnace under air atmosphere. The results indicate that microstructure at room temperature consisted of a mixture of β3(L21) parent phase with 0.06–0.08 at% of vanadium into solid solution, small amounts of a cubic bcc δ(V,Mn) precipitate, β1′(18R) and γ1′(2H) martensites. The small addition of vanadium contributes to the induction of martensite γ1′ and broads the hysteresis of the alloys. Thermal analysis evidences the shift of Af, Ms to higher temperatures, showing multi-stage phase transformations of the reaction β1′→γ1′→β3, which results in increased values of ΔHM→A, ΔSM→A, ΔGe. The addition of V also interfered in the corrosion resistance of the alloy. Electrochemical measurements were carried out to evaluate the corrosion resistance alloys. With the results obtained, an increase in corrosion resistance was observed with the increase in the vanadium content in the alloy. The results of this work provide an important systematic analysis for the development and application of corrosion resistant CuAlMn SMA.

Improving the Properties of High-Strength Steel for Critical Components by Microscopic Additions of Vanadium and Nitrogen

Improving the Properties of High-Strength Steel for Critical Components by Microscopic Additions of Vanadium and Nitrogen

Effects of Vanadium Microalloying and Intercritical Annealing on Yield Strength–Ductility Trade-Offs of Medium-Manganese Steels

In this paper, we investigate the effects of vanadium on the strength and ductility of medium-manganese steels by analyzing the microstructural evolution and strain hardening rates and performing quantitative calculations. Two significantly different contents of vanadium, 0.05 and 0.5 wt.%, were independently added to model steel (0.12C-10Mn) and annealed at different intercritical temperatures. The results show that higher vanadium addition increases the yield strength but decreases the ductility. The maximum yield strength can increase from 849 MPa to 1063 MPa at low temperatures. The model calculations reveal that this is due to a precipitation strengthening increment of up to 148 MPa and a dislocation strengthening increment of 50 MPa caused by a higher quantity of V4C3 precipitates. However, the high density of vanadium carbides leads them to easily segregate at grain boundaries or phase interfaces, which prevents strain from uniformly distributing throughout the phases. This results in stress concentrations which cause a high strain hardening rate in the early stages of loading and a delayed transformation-induced plasticity (TRIP) effect. Additionally, the precipitates decrease the austenite proportion and its carbon concentrations, rendering the TRIP effect unsustainable. Accordingly, the ductility of high vanadium steels is relatively low.

Synthesis and evaluation of rocksalt structure (Mo, W) carbides via vanadium additions

The mechanical properties of rocksalt (B1) binary, ternary, and high entropy transition metal ceramics exhibit strong correlation with their valence electron concentration (VEC). With respect to maximizing ductility and hardness, it has been proposed that materials with VEC values between 9 and 10 will generally possess superior performance. While many of the transition metal cations inherently crystallize in the B1 structure, the VEC=10 Group-VIB elements don't form room temperature stable B1 carbides. This work demonstrates the ability to stabilize bulk, spark plasma sintered samples of the Group-VIB containing carbides with VEC values in this range. The stabilization of molybdenum and tungsten carbide as room-temperature B1 structures via the addition of different amounts of vanadium and nanoindentation measurements correlated with VEC are the primary goals of this work. The minimum atom percent vanadium to form a single-phase B1 carbide is thoroughly explored and verified via a combination of XRD, EDS, and EBSD.

ATI 8-1-1

Abstract ATI 8-1-1 (UNS R54810) is a near-alpha alloy with aluminum being the alpha stabilizer, and the additions of molybdenum, vanadium, and iron resulting in small amounts of beta. This alloy is used in the annealed condition, and special duplex annealing procedures have been developed for thick sections such as bars and forgings. It is intended primarily for use at elevated temperatures. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on forming, heat treating, machining, and joining. Filing Code: Ti-190. Producer or source: ATI.

Influence of Microalloying on the Microstructures and Properties of Spalling-Resistant Wheel Steel

Microalloyed steels have emerged to replace conventional plain-carbon steels to achieve longer wheel life on Chinese railroads. In this work, with the aim of preventing spalling, a mechanism that consists of ratcheting and shakedown theory correlated with steel properties is systematically investigated. Mechanical and ratcheting tests were carried out for microalloyed wheel steel to which vanadium was added in the range of 0-0.15 wt.% and the results were compared with that obtained for conventional plain-carbon wheel steel. The microstructure and precipitation were characterized via microscopy. As a result, the grain size was not obviously refined, and the pearlite lamellar spacing decreased from 148 nm to 131 nm in microalloyed wheel steel. Moreover, an increase in the number of vanadium carbide precipitates was observed, which were mainly dispersed and uneven, and precipitated in the pro-eutectoid ferrite region, in contrast to the observation of lower precipitation in the pearlite. It has been found that vanadium addition can lead to an increase in yield strength by precipitation strengthening, with no reduction or increase in tensile strength, elongation or hardness. The ratcheting strain rate for microalloyed wheel steel was determined to be lower than that for plain-carbon wheel steel via asymmetrical cyclic stressing tests. An increase in the pro-eutectoid ferrite content leads to beneficial wear, which can diminish spalling and surface-initiated RCF.

Effect of vanadium on Nicotiana tabacum L. grown in vanadium-loaded soil

ABSTRACT Tobacco exhibited a relatively strong environmental adaptability, and it is appealing to explore its vanadium stress-responsive characteristic. An indoor pot experiment with tobacco cultivated in soil with respectively 0 (control), 75, 150, 300, 600, and 900 mg kg−1 of exogenous pentavalent vanadium V(V) and in vanadium-rich soil from a mining area with 385.6 mg kg−1 of vanadium (marked as M0) was conducted. Results showed that tobacco growth was significantly (p< 0.05) inhibited at all treatments versus control. The seedlings could not survive at 900 mg kg−1 vanadium treatment. Vanadium was mainly concentrated in the root. Tobacco showed a relatively high vanadium bioconcentration capability (0.19 − 0.74) and a low translocation capability (0.02 − 0.03) in soil with exogenous vanadium addition treatments. Contrarily, at the control and M0 treatment, tobacco exhibited a low vanadium bioconcentration capability (0.06 − 0.08) and a relatively high translocation capability (0.06 − 0.09). For M0 treatment, the high percentage of vanadium in the residual fraction was also conducive to tobacco establishment in vanadium-loaded surroundings. Overall, tobacco showed the potential to colonize vanadium-rich soil. In soils after growing tobacco, Proteobacteria was the most abundant microbial community of the rhizospheric soil, followed by Actinobacteria.

Hardening Due to Vanadium Carbides Formed During Short-Time Aging of Hadfield Steels

Precipitation hardening is a promising approach for strengthening of Hadfield steels. The present study examines the potential to achieve this by combining vanadium addition (up to 2 wt pct) with short-time aging (15 minutes) at 1173 K (900 °C). It was found that such a treatment is sufficient to generate a dispersion of nanoscale precipitates that provided a significant increase in hardness. Small-angle neutron scattering and transmission electron microscopy measurements were performed to quantify the particle dispersion, and Orowan precipitate hardening predictions made using the parameters thus obtained show good correspondence with the observed rates of age hardening, suggesting the precipitates are resistant to shearing. The present steels containing vanadium showed a small reduction in work-hardening capacity and this is believed to be due to carbon depletion from the matrix. It is concluded that the addition of vanadium and a short aging treatment at 1173 K (900 °C) provide a promising pathway to imparting hardness increases that provide gouge resistance during the running-in period of components made from Hadfield steel. For optimum performance, additional carbon should be added to maintain the solute carbon content of the matrix, and hence the matrix work-hardening rate.

Concept for development of economically alloyed ausferritic (bainitic) ductile cast irons

The distribution of the castings production in the world, whose total output is more than 112 million tons, is considered. A steady trend to the replacement of rolled alloy steel, which is used for critical engineering products, by Austempered Ductile Iron (ADI) is outlined. The latter is ductile cast iron with globular graphite, which is austempered (isothermally quenched) to produce ausferritic (bainitic) structure. The dynamics of prices for main alloying elements in ADI (molybdenum, nickel and copper, whose total amount in the alloy reaches 5 %) is considered and their steady growth is outlined.The research goal is to develop a concept of economical alloying of ADI (the total content of Mo, Ni and Cu should not exceed 2 %) retaining sufficient hardenability and substantially decreasing the cost price. The goal is attained by decreasing the content of the most expensive alloying element, molybdenum, to a minimal level along with the use of microalloying and applying one of the methods of hot plastic deformation to the casting.The reduced content of the main ‘triad’ of alloying elements is compensated by microadditives of strontium or barium, vanadium, boron, niobium and the addition of misch metal. Several groups of economically alloyed cast irons are proposed: (1) low‑nickel and low‑molybdenum with increased content of copper (up to 1.8 %) and the addition of vanadium, (2) molybdenum‑free with microadditive of boron, (3) molybdenum‑free with microadditives of niobium and boron, and (4) molybdenum‑free minimally alloyed with nickel and copper.It is shown that plastic deformation, along with giving the product the required shape, affects the kinetics of structural‑phase transformations. and acts similarly to alloying with Mo and Ni, shifting the TTT‑curve to the right. Therefore, the ausferritic structure can be obtained at a lower cooling rate.The mechanical properties with such alloying and the use of plastic deformation are the following: ultimate tensile strength 1100–1500 MPa and elongation to failure 2–4 % for lower bainite; ultimate tensile strength 800–1100 MPa and elongation to failure is 4–7 % for upper bainite.

Investigation of the phase composition and structure of stationary catalysts to increase safety of agrarian-and-food production

The phase composition and structure of stationary nickel-aluminum promoted catalysts have been studied. It is shown that the phase composition of the catalysts consists of intermetallic compounds NiAl, NiAl3, Ni2Al3. Changes in the microscopic structure of the alloys are determined. Modern methods for evaluating hydrogenation catalysts, as well as methods for analyzing raw materials and products of catalytic hydrogenation, have been established. The highest hydrogenation performance is characteristic of stationary catalysts whose alloys consist of Ni2Al3×4NiAl3 intermetallic compounds. New modifications of stationary alloyed nickel-copper-aluminum catalysts with the addition of vanadium (0.5-2.5 %), rhodium (0.5 %) and palladium (0.05 %) in the process of pre- contact hydrogenation of cottonseed oil have been studied and developed. It has been shown that the lowest content of transisomerized acids in tallow is achieved at a content of 1.5 % vanadium in a stationary promoted catalyst. The content ratio of the fatty-acid composition in the triglycerides of target dietary fats was determined, ensuring their increase in nutritional value and safety. The conditions under which the highest results were obtained are presented.

The mechanism of increasing the wear resistance of steel 110G13L by modification, dispersion and dispersion nitride hardening

The current state of industrial production of wear-resistant cast parts from high-manganese steels using various alloying, micro-alloying and modification technologies is analyzed in order to increase wear resistance not only in conditions of shock-abrasive, but also in conditions of purely abrasive wear. It is shown that despite the large number of technologies for the production of wear-resistant parts from these steels, there are no simple and highly effective methods. Prospective directions are dispersion hardening of metal by modification and microalloying of steels, in particular with nitrogen and vanadium, dispersion hardening by alloying of steels with titanium, niobium, etc. and the use of optimal modes of heat treatment. For the conditions of intensive shock-abrasive wear, it is important to establish the regularities of the influence of the degree of shock deformation on the formation of the surface martensitic layer in products after microalloying and modification of steels with nitrogen, dispersion and dispersion nitride hardening of the metal. It has been shown that dispersion nitride strengthening of metal by modifying steel with nitrogen or joint addition of nitrogen and vanadium to it and dispersion strengthening of metal after simultaneous addition of nitrogen, titanium and niobium significantly disperse the austenite grain of steel both in the cast state and after quenching. The change in the structure of steels due to the strengthening of the metal significantly affects their mechanical properties after various modes of heat treatment. Dispersive vanadium nitride strengthening increases strength by 15...17 % and plasticity by 45...50 %, and dispersed nitride strengthening increases plasticity by 45...60 % while maintaining the level of strength and slightly reducing impact toughness. The influence of the degree of impact deformation on the formation of e and a-martensite is shown, and a clear relationship between the increase in the degree of impact deformation and the increase in the amount of a-phase in the deformed layer is established. Impact deformation of about 16.6 % increases the amount of a-martensite in the deformed layer from 40 % to 98 %, which ensures an increase in the hardness of the deformed layer from 24 HRC to 36 HRC. It was noted that nitrogen modification, dispersion nitride and impact hardening of high-manganese steels increase their wear resistance by 1.5...2.0 times under conditions of dry sliding friction and 1.7...2.0 times under conditions of abrasive wear using unfixed and fixed abrasive.

Study on the Microstructure of Vanadium-Modified Tungsten High-Speed Steel-Coded SAE-AISI T1 Steel

The essential goal of this research is to evaluate the modification process on phase transformation, matrix chemical composition, and precipitated carbide types for modified SAE-AISI T1 steel and their effects on the hardness values after optimum heat treatment conditions. This research adopts the alloying design strategy to enhance one of the most important tools steel coded SAE-AISI T1 (T12001). Therefore, two alloying enhancement processes took place through partial or total tungsten replacement. Investigated steel was modified first through the addition of vanadium and then through the addition of vanadium and carbon. Substitute 5 wt modified SAE-AISI T1 steel. % tungsten with 1 wt. % vanadium, in addition to carbon content, varied from 0 to 1 wt. %. Therefore, to fulfill the goals of this work, Thermo-Calc software was utilized to get the following: (i) thermodynamic equilibrium information, (ii) the expected microstructure, (iii) the constituent volume fraction, and (iv) carbide chemical composition. The chemical composition of the expected phases was confirmed by scanning electron microscopy (SEM) equipped with energy-dispersive X-ray (EDX). In addition, volume fractions of different constituents were estimated by using Thermo-Calc software and authenticated by the imaging analysis process. The experimental findings for the variations in the chemical composition of the matrix and eutectic carbides precipitated, e.g., MC and M6C carbides, agree well with the calculated findings. Tungsten replacement by vanadium with and without extra carbon at traditional SAE-AISI T1 steel encourages MC carbide formation instead of M6C, M23C6, and M7C3 carbides. MC carbide precipitated in vanadium with extra carbon-modified steel contains more carbon, chromium, and tungsten but less vanadium compared with vanadium-modified steel. Vanadium with extra carbon-modified steel precipitated more M6C carbide and gamma-austenite. Hardness measurements emphasized that modified steel is a promising material for its use as a tooling material with low tungsten content and, in turn, produces cutting-tool materials with economical cost.

Photocatalytic degradation of naproxen using single-doped TiO2/FTO and co-doped TiO2-VO2/FTO thin films synthesized by sonochemistry

Abstract Single-doped TiO2/FTO and co-doped TiO2-VO2/FTO thin films were prepared by sonochemistry and spray pyrolysis deposition on FTO substrates. The co-deposition of TiO2-VO2 on FTO significantly changed the morphological, structural, optical, and photocatalytical properties compared to the single-deposition. X-ray diffraction and HRTEM results showed polycrystalline film structures composed of SnO2-tetragonal from FTO, anatase-TiO2, rutile-TiO2, and monoclinic-VO2 phases. The co-deposition technique increases the particle size distribution by approximately two times compared to simple deposition. The single-doped TiO2/FTO thin film had a 15% higher bandgap than the co-doped TiO2-VO2/FTO thin film, and the electrical resistivity calculated from the van der Pauw method was 55.3 MΩ sq−1 for the TiO2-VO2/FTO co-doped thin film, 2.7 times lower than that obtained for the TiO2/FTO thin film. Single-doped TiO2/FTO and co-doped TiO2-VO2/FTO thin films presented pseudo-first-order reactions at pH 6.5, with kinetic constants of 0.026 and 0.015 min−1, respectively. This behavior is related to the production of inactive or less active aggregates by the addition of vanadium during the co-doping process, which led to lattice contraction, which encouraged the formation of the rutile phase rather than the anatase phase. However, the co-doped thin film can modify the metal-insulator transition compared to the single-doped TiO2/FTO thin film. Furthermore, co-deposition decreased the bandgap value by 16% compared to single-deposition thin film. In this sense, co-doped TiO2-VO2/FTO thin films inhibited the recombination of photogenerated carriers and the formation of reactive oxygen species involved in the photocatalytic degradation of naproxen.

Lubricant oil & Diesel analysis based diagnostic framework for machine components & V-Ti ceramics as additives for lubricants and plasticizers

In this paper, typical failures of major engine machinery component’s are analyzed using the knowledge of oil analysis. Information of elements obtained from oil analysis and related details, using the practical knowledge, is used for; analysis of oil thickening, low viscosity analysis, framing decision, maintenance scheduling and diagnostic procedure. Accordingly, systematic procedure is framed using knowledge of different oil elements; viz. Lead, Tin, Copper, Chromium, Silicon, Aluminum and Iron in the context of the corrective action. Poor atomization of diesel fuel related causes are briefed. Novel metal ceramic additives of Vanadium (V) and Titanium (Ti), developed using sol–gel method are detailed and preliminary results are presented with and without additives incorporated in used ester oil with key focus on lowering total acid number (TAN) and saponification value. Density & viscosity are investigated too. One of the key novelty of the work is developing blends of V-Ti (fine powder form) at low temperature safely & inexpensively by using Metal Nitrate (new reactions as a result) as against traditional metal alkoxide in the sol gel method and utilizing them to reduce TAN and saponification of used oil. Developed procedure and ceramics will be useful for practicing engineers, scientists in reducing maintenance, making sustainable product, reducing pollution and new system design using novel materials.

Effect of vanadium alloying on microstructure and wear behavior of two-body abrasive particles of Fe–5.5 wt% B surfacing alloy

The effects of vanadium addition on the microstructure and two-body abrasive wear behavior of an Fe–5.5 wt.% B surfacing alloy prepared by the plasma arc welding technique were investigated. The results show that the Fe–5.5 wt.% B surfacing alloys with different contents of vanadium are mainly composed of the primary Fe 2 B phase, Fe 2 B+Fe eutectic structure, and a vanadium boride (VB) precipitate. With increasing vanadium content in the Fe–5.5 wt.% B surfacing alloys, the number of microcracks in the primary Fe 2 B phase decreases, and the microcracks finally disappear, while the volume fraction of VB increases concurrently. The primary Fe 2 B phase can be remarkably refined, and the growth orientation changes from preferential to disordered staggered growth. The hardness of the surfacing alloy shows a trend of initial increase and subsequent decrease. Meanwhile, the wear resistance of the two bodies shows a continuous increasing trend, and the change trend is the same under contact loads of 24 N and 48 N. Alloying element V can effectively refine the primary Fe 2 B, promote the precipitation of VB, and form a microstructure reinforced by fine interlaced rod-shaped Fe 2 B and spherical VB, which effectively improves the crack resistance and wear resistance of the surfacing alloy.

The Effect of the Dilution Level on Microstructure and Wear Resistance of Fe-Cr-CV Hardfacing Coatings Deposited by PTA-P

Soil preparation tools are subject to severe abrasion. The wear resistance of various industrial components can be improved using the hardfacing technique. The improvement in hardfacing wear resistance depends on the microstructure, i.e., the chemical composition of the alloys, the method of overlay, and the parameters of the selected process. The Plasma Transferred Arc with Powder (PTA-P) welding process is interesting as a hardfacing technique since it promotes very low dilution of the substrate in the coating. In this article, the PTA-P welding process was used for the deposition of Fe-Cr-C-based hard coatings with the addition of vanadium onto cheap and relatively soft low-carbon steel substrates. Rubber-wheel abrasion tests were performed to compare the abrasion resistance between commercial anti-wear steel and weld-deposited Fe-Cr-C-V hard coatings. In addition, the microstructure, dilution, and wear mechanisms were investigated. The dilution of the coatings affected the microstructure, in particular, the free mean path of the vanadium carbides, but it only affected abrasion resistance when the wear mechanism involved rolling abrasion. The deposited coatings proved to be at least three times stronger than a commercial abrasion-resistant steel due to the distribution and morphology of the vanadium carbides formed in the coatings.

Exploration of V–Cr–Fe–Co–Ni high-entropy alloys with high yield strength: A combination of machine learning and molecular dynamics simulation

Improving the strength of Cr–Fe–Co–Ni high-entropy alloys is a key issue in expanding their applicability. Herein, a framework combining machine learning and molecular dynamics is employed to improve the yield strength of Cr–Fe–Co–Ni high-entropy alloys through vanadium addition. The results indicate that by specifying the valence electron concentration, vacancy formation energy, and mismatch in cohesive energy as input features, a support vector regression model with a radial bias function kernel displays the highest performance among numerous combinations of machine learning models and material features. According to the Shapley additive explanation, the vacancy formation energy and valence electron concentration show a negative correlation with the yield strength above 1.66 eV and 7.60, respectively, and a positive correlation otherwise. The mismatch in the cohesive energy always shows a negative correlation. By utilizing a Bayesian adaptive alloy design, V5Cr16Fe9Co35Ni35 has been identified to have the highest yield strength. The simulated tensile deformation of polycrystalline high-entropy alloys confirms the predicted trend in yield strength, and the events observed during plastic deformation are consistent with previous experimental observations. The proposed framework provides a promising prospect for accelerating the design of high-entropy alloys with reduced dependence on costly trial-and-error experiments.

Effect of Vanadium on the Microstructure, Transformation Temperatures, and Corrosion Behavior of NiTi Shape Memory Alloys

Abstract Ni50Ti50-xVx (x = 0, 1, 2, 3 at%) shape memory alloys were prepared by vacuum induction melting. They were homogenized and then hot rolled. Carbon hydrogen nitrogen oxygen sulfur (CHNOS) and X-ray diffraction (XRD) analyses were carried out on the alloys to find out the oxygen and carbon contents and the phases present in the alloys. Transformation temperatures determined by differential scanning calorimetry indicate that the addition of vanadium reduces the transformation temperatures. Corrosion studies were carried out in Hanks’ solution, while potentiodynamic polarization tests were done to calculate the rate of corrosion of the alloys. Two significant parameters were analyzed from the Tafel graph, namely, corrosion rate and corrosion potential. A comparison of these properties of the alloys was also made with commercially pure titanium and binary NiTi alloys. Among the NiTiV alloys, Ni50Ti47V3 (at%) alloy was found to undergo the least rate of corrosion. With the increasing vanadium content, the rate of corrosion was found to decrease. Scanning electron microscopy (SEM) analysis of the corroded surface shows that pitting was the main mechanism of corrosion in these alloys. Results show that the addition of V to NiTi has a positive effect on the corrosion properties of the alloys. Elaborate results are discussed in detail in this article.

Effects of Vanadium Addition on Strain Distribution, Crack Initiation and Propagation during Low-cycle Fatigue Test in Ferrite and Martensite Dual-phase Steel

Effects of Vanadium Addition on Strain Distribution, Crack Initiation and Propagation during Low-cycle Fatigue Test in Ferrite and Martensite Dual-phase Steel

Influence of vanadium addition on corrosion behavior of high‐energy ball milled aluminum alloy 2024

AbstractThe effect of V addition on the hardness and corrosion of aluminum alloy 2024 (AA2024) produced by high‐energy ball milling has been investigated. High‐energy ball milled alloys exhibited enhanced solid solubility of alloying elements and ultrafine grains. The addition of V improved the corrosion resistance of the AA2024 alloy, which was attributed to the deposition of V on the cathodic particles and therefore decrease in their ability to sustain large cathodic currents.