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The motivation of this study is to develop and investigate the properties of nanocoated reinforcements against corrosion instead of previously used cathodic protection, epoxy coatings (that reduces reinforcement and concrete adherence) or organic and inorganic inhibitors. The purpose of conducting this manuscript is the comparison of the corrosion resistance of coated and uncoated reinforcements. Reinforced concrete steels were coated for the first time in the structural area with nanocoatings by thermionic vacuum arc (TVA) system. When we compare the TVA system with other systems in the literature, the system we recommend allows high adhesion and high-quality coatings at very low temperatures. The innovative side of this investigation was development of nanocoatings that increase the corrosion resistance of structural steels. In this research; Zinc (Zn), Zinc-Boron (Zn-B) and Zinc-Boron-Nitrogen (Zn-BN) nanocrystal coatings were applied to reinforced concrete reinforcements with Thermionic Vacuum Arc (TVA) system. Then, the corrosion rates of coated and uncoated reinforcements were compared with accelerated corrosion tests. After these tests, the real weight losses were determined by removing the reinforcements in the specimens. The real weight loss that occurred after exposing the reinforcement to corrosion effect was compared with the theoretical weight loss calculated from the Faraday equation. The experimental results showed that; compared to the uncoated reinforcements, the initial corrosion currents of the ZN, ZN-B, ZN-BN coated reinforcements decreased by 93.9%, 93.0 and 95.1%, respectively, and the real weight losses caused by corrosion decreased by 32.67%, 50.64% and 90.08% in Zn, Zn-B and Zn-BN nanocoatings, respectively. [ABSTRACT FROM AUTHOR]

Oxidation of the Nd-rich phase in Nd-Fe-B magnet alloys is known to deteriorate their coercivity. Therefore, it is important to prevent the dissolution of oxygen into the NdFeB magnet alloy during the manufacturing process. This requires the knowledge of the properties of oxygen in NdFeB magnet alloys, which has not been investigated yet. In this study, the oxygen solubility of Nd-Fe-B alloy at 1673K was measured, and the effect of boron concentration on the affinity between oxygen and NdFeB alloy was analyzed. The standard Gibbs energy for the dissolution of oxygen into the molten NdFeB alloy at 1673K was derived from experimental results, which indicated that the addition of boron into the molten Nd-Fe alloy decreased the affinity between oxygen and the alloy. The thermodynamic cause of this effect of boron is discussed, and a method to suppress oxygen dissolution into NdFeB alloy during the melt manufacturing process is suggested. [ABSTRACT FROM AUTHOR]

The elastic properties of alloys between boron suboxide (B6O) and boron carbide (B13C2), denoted by (B6O)1-x(B13C2)x, as well as boron carbide with variable carbon content, ranging from B13C2 to B4C are calculated from first-principles. Furthermore, the mixing thermodynamics of (B6O)1-x(B13C2)x is studied. A superatom-special quasirandom structure approach is used for modeling different atomic configurations, in which effects of configurational disorder between the carbide and suboxide structural units, as well as between boron and carbon atoms within the units, are taken into account. Elastic properties calculations demonstrate that configurational disorder in B13C2, where a part of the C atoms in the CBC chains substitute for B atoms in the B12 icosahedra, drastically increase the Young' and shear modulus, as compared to an atomically ordered state, B12(CBC). These calculated elastic moduli of the disordered state are in excellent agreement with experiments. Configurational disorder between boron and carbon can also explain the experimentally observed almost constant elastic moduli of boron carbide as the carbon content is changed from B4C to B13C2. The elastic moduli of the (B6O)1-x(B13C2)x system are also practically unchanged with composition if boron-carbon disorder is taken into account. By investigating the mixing thermodynamics of the alloys, in which the Gibbs free energy is determined within the mean-field approximation for the configurational entropy, we outline the pseudo-binary phase diagram of (B6O)1-x(B13C2)x. The phase diagram reveals the existence of a miscibility gap at all temperatures up to the melting point. Also, the coexistence of B6O-rich as well as ordered or disordered B13C2-rich domains in the material prepared through equilibrium routes is predicted. [ABSTRACT FROM AUTHOR]

The structures and magnetic properties of Co-Zr-B alloys near the composition of Co5Zr with B at. % ≤6% were studied using adaptive genetic algorithm and first-principles calculations. The energy and magnetic moment contour maps as a function of chemical composition were constructed for the Co-Zr-B magnet alloys through extensive structure searches and calculations. We found that Co-Zr-B system exhibits the same structure motif as the "Co11Zr2" polymorphs, and such motif plays a key role in achieving strong magnetic anisotropy. Boron atoms were found to be able to substitute cobalt atoms or occupy the "interruption" sites. First-principles calculations showed that the magnetocrystalline anisotropy energies of the boron-doped alloys are close to that of the high-temperature rhombohedral Co5Zr phase and larger than that of the low-temperature Co5.25Zr phase. Our calculations provide useful guidelines for further experimental optimization of the magnetic performances of these alloys. [ABSTRACT FROM AUTHOR]

The standard Gibbs energies of formation, ΔfGo, of CrB4, CrB2, Cr3B4, Cr5B3, and CrBO3 existing along the oxidation path of CrB binary alloy were determined using the electromotive forces of galvanic cell composed of the ZrO2Y2O3 solid electrolyte. The electromotive force showed plateaus and decreases in the process that CrB4CrB2 two-phase alloy used for the cell materials were oxidized via two- and three-phase regions along its oxidation path. From the plateaus of electromotive forces corresponding to the cell materials in the three-phase regions, the values of ΔfGo(CrB4), ΔfGo(CrB2), ofGo(Cr3B4), ΔfGo(Cr5B3), and ΔfGo(CrBO3) in the temperature range from 1273 to 1346K were determined as follows:ΔfGo(CrB4)/J (mol of compd.)¹1 = 167500 ¹ 261.2 T « 7200 ΔfGo(CrB2)/J (mol of compd.)¹1 = ¹21020 ¹ 79.22 T « 2100 ΔfGo(Cr3B4)/J (mol of compd.)¹1 = ¹173400 ¹ 95.47 T « 2500 ΔfGo(Cr5B3)/J (mol of compd.)¹1 = ¹318900 + 20.64 T « 5800 ΔfGo(CrBO3)/J (mol of compd.)¹1 = ¹958800 + 59.24 T « 4100 The ΔfGo values determined in the present study satisfied the phase equilibria in the CrB binary system. Using the determined ΔfGo values, the composition-oxygen partial pressure diagram of the CrBO system was constructed under the conditions at 1300K and a total pressure of 1 bar (100 kPa). It is useful to understand the oxidation property of the CrB binary alloys. [ABSTRACT FROM AUTHOR]

Light-induced degradation (LID) is a deleterious effect in crystalline silicon, which is considered to originate from recombination-active boron-oxygen complexes and/or copper-related defects. Although LID in both cases appears as a fast initial decay followed by a second slower degradation, we show that the time constant of copper-related degradation increases with increasing boron concentration in contrast to boron-oxygen LID. Temperature-dependent analysis reveals that the defect formation is limited by copper diffusion. Finally, interface defect density measurements confirm that copper-related LID is dominated by recombination in the wafer bulk. [ABSTRACT FROM AUTHOR]

In order to understand the characteristics of the wastewater treatment method using zero-valent magnesium granules, the reaction between an aqueous solution containing boron and zero-valent magnesium granules was investigated by experiments and a reaction rate model. Particular attention was paid to the effect of adding hydrochloric acid before adding zero-valent magnesium and to the effect of adding sodium hydroxide to adjust the pH to 10.5 after 110 minutes. The following findings were obtained. The relationship between the pH and the dissolved magnesium concentration over time is determined by a reaction formula in which zero-valent magnesium granules react with an aqueous solution to generate Mg2+ ions while generating hydrogen. When magnesium hydroxide is produced, the pH becomes constant over time. Increasing the concentration of hydrochloric acid lowers the pH value reached. This relationship is determined in equilibrium with magnesium hydroxide. The reaction rate of the zero-valent magnesium granules is determined as the first-order reaction of the hydrogen ion activity when the pH was lower than 2.3 or higher than 8.5, and as the zero-order reaction of the hydrogen ion activity at pH from 2.3 to 8.5. The amount of magnesium hydroxide produced without the addition of sodium hydroxide is determined by the above-described reaction rate model of zero-valent magnesium granules. The boron concentration of the solution when the pH is adjusted to 10.5 by adding sodium hydroxide is determined by the Langmuir-type sorption isotherm of boron to the magnesium hydroxide produced. As described above, the behavior of removing boron from an aqueous solution using zero-valent magnesium granules can be well reproduced by the simple reaction rate model used in this study, and it can be said that it is useful for process design. [ABSTRACT FROM AUTHOR]

Conventional non‐rare‐earth permanent magnet (PM) electrical machine can hardly achieve comparable performance with the neodymium iron boron (NdFeB) machine due to the low coercivity and remanence. To solve this problem, a new kind of electrical machine using only Alnico magnet is proposed in this study. The novel rotor topology eliminates rotor iron core, and thus effectively limits armature reaction and improves torque density. A kind of rapid assessment method for the demagnetisation effect of q current in different slot–pole combinations through magnetomotive force and winding factor is presented and verified by 2D finite‐element analysis. The optimisation of critical dimensions is demonstrated, and the trade‐off between high PM utilisation and low demagnetisation effect is emphasised. After that, the good torque–current linearity and robust to demagnetisation characteristics of the proposed topology are proved through a comparison with two rare‐earth‐free machines. Finally, the performance comparison with a manufactured conventional NdFeB machine under the same volume constraints is provided. The result suggests that the proposed machine has a higher power factor, lower eddy‐current loss, and rare‐earth PM machine comparable torque density. [ABSTRACT FROM AUTHOR]

Most of the conventional linear generator is constructed with either Alnico (specially AlNiCo‐9) or Neodymium iron boron (NdFeB) permanent magnets (PMs) for harvesting oceanic wave energy. Alnico is a composition of aluminium (Al), nickel (Ni), and cobalt (Co) added to iron, which is its major volumetric component. Alnico has a poor magnetic energy product, and NdFeB contains a rare earth element. To overcome this issue, a recently developed rare‐earth free iron nitride (Fe16N2) compound‐based PM linear generator (PMLG) is proposed in this study as an alternative solution for avoiding rare earth material while obtaining high output power. To the best of authors' knowledge, newly invented Fe16N2 is not proposed, analysed, and investigated in any electrical generator. In this context, Fe16N2 is proposed in a linear generator as PM for producing adequate magnetic flux. For analysis and testing the performance of the proposed material, a PMLG is designed. The performances are compared for using Fe16N2 and AlNiCo PMs in the same PMLG design for a fair comparison. It is considered that the proposed PMLG is connected to a direct drive power take‐off system. Simulation results show that the proposed PMLG having Fe16N2 generates 55% more electrical power than that of using AlNiCo. The voltage, current, magnetic flux linkage, power, and magnetic flux density of the proposed PMLG are investigated extensively and compared with those of AlNiCo. The finite element method is applied in the ANSYS/Maxwell software environment for testing the PMLG with the conventional and the proposed PMs as well as results are presented. The proposed design is also validated with a small laboratory prototype. [ABSTRACT FROM AUTHOR]

We have studied the energy absorption buildup factors and specific absorbed fraction of energy for the silicon-boron alloys of different composition such as alloy A-Si0.95-B0.05, alloy B- Si0.9-B0.1, alloy C- Si0.8-B0.2, alloy D- Si0.7-B0.3, alloy E- Si0.6-B0.4 and alloy F- Si0.5-B0.5. for wide energy range (0.015-15 MeV) up to the penetration depth of 40 mfp using geometric progression fitting method. Buildup factors increase with the increase in the penetration depth. It has been found that the shielding parameters such as mass attenuation coefficient, effective atomic number and buildup factor values are larger for the silicon-boron alloy Si0.95-B0.05 than the other studied silicon-boron alloys. Specific absorbed fraction of energy is maximum for the silicon-boron alloy Si0.95-B0.05. Hence, we can conclude that the silicon-boron alloy Si0.95-B0.05 is a good absorber of X-rays, gamma and neutrons among the studied alloys. The present study is useful in the field of radiation shielding. [ABSTRACT FROM AUTHOR]

The torque density characteristics for an axial flux magnetic gear using a flux‐focusing topology is experimentally studied when using neodymium iron boron (NdFeB) rare‐earth magnets. A geometric parameter sweep analysis was utilised in order to maximise both the calculated volumetric and mass torque density. The calculated torque and torque density was 628.6 N·m and 173.02 N·m/L while the experimentally measured torque and resultant torque density was 553.2 N·m and 152.3 N·m/L. [ABSTRACT FROM AUTHOR]

Abstract Boron dipyrromethene (BODIPY) derivatives have good optoelectronic properties and thermal stability. However, it is rarely for such materials to use in bulk heterojunction (BHJ) organic solar cell. In this study, a variety of donor-acceptor (D-A) type boron dipyrromethene (BODIPY) based dyes were designed and synthesized for polymer solar cells (PSCs), namely BDH1-4. Thermal stability, photochemical properties, charge transport and BHJ morphology were investigated to elucidate factors affecting the photovoltaic performance in this class of polymers. These BDHs exhibit fine solubility in conventional solvents, good thermal stability, excellent panchromatic absorption in solution and in film. Furthermore, the absorption wavelength of BDH1-4 covers full color absorption in the range of 300–800 nm and has a relatively low HOMO level from −5.01 to −5.66 eV. Among them, BDH4 / PC 71 BM based PSCs exhibit highest power conversion efficiency (PCE) of 3.69% with a Jsc of 9.92 mA cm−2, a Voc of 0.63 V and a FF of 59.1%. Graphical abstract Four D-A type BODIPY based dyes were designed and synthesized for polymer solar cells (PSCs). All these polymers show appealing photovoltaic performance. Among them, BDH4/PC 71 BM based PSC exhibit not only good photoelectric characteristic but also good hole mobility and surface morphology relative to the other counterparts and thus pronounce to a higher PCE of 3.69% with a Jsc of 9.92 mA cm−2 and a FF of 59.1%. Image 1 Highlights • A series of novel D-A type dyes based on BODIPY were synthesized for PSCs. • Polymer BDH4 exhibited the highest PCE value of 3.69% with PC 71 BM. • Several factors influencing the efficiency of PSCs were demonstrated. [ABSTRACT FROM AUTHOR]

Abstract Two metallurgical purification techniques, namely solvent refining and slag treatment, were combined to remove boron from silicon. Silicon was alloyed with iron and the alloy was subjected to slag treatment by a ternary of CaO-SiO 2 -Al 2 O 3 at 1600 °C (1873 K). Effects of oxygen potential and basicity of slag on boron removal were investigated through changing the SiO 2 /Al 2 O 3 and CaO/SiO 2 ratios, respectively. Results indicate that these two parameters have major effects on partition ratio of boron. A critical oxygen potential value, which yields the highest partition ratio of boron, was calculated as approximately 9 × 10−18 atm. Partition ratio of boron was normalized with oxygen potential at each slag composition in order to isolate the effect of basicity. Borate capacity values were calculated for different slags and it was shown that this parameter is only a function of temperature and slag composition. The kinetics of boron removal was quantified and the total mass transfer coefficient of boron was calculated as 7.48 × 10−6 cm/s. Highlights • A metallurgical method was applied for boron removal from silicon. • A critical oxygen potential, that yields the highest boron removal, was calculated. • Boron distribution was normalized by oxygen potential at each slag composition. • Total mass transfer coefficient of boron was calculated by a kinetic analysis. [ABSTRACT FROM AUTHOR]

Continuous cooling transformation (CCT) characteristics and prior-austenite grains of boron microalloyed steels with and without titanium were investigated to obtain the necessary information for heat treatment of these steels. Transformation characteristics were determined by using dilatometer tests, microscopic observation, and hardness measurements. In addition, the effects of titanium addition on the sizes of prior-austenite grains and precipitates were analysed. The results show that the changes in austenite grain size are not very distinct, and adding titanium only slightly refines the austenite grains. The CCT diagrams showed that the ranges of transformation products were shifted to the right side by the addition of titanium. The ferrite transformation starting temperatures were reduced on addition of titanium. Titanium addition induced decreased critical cooling rates for bainite transformations. The hardenability of boron microallyed steel is increased by adding titanium because more boron segregate to prior-austenite grain boundaries. [ABSTRACT FROM AUTHOR]

Phase selection, a common and important phenomenon in rapid solidification, determines the solidification sequence and the mechanical/physical properties. In this work, a Co-20 at%B hypereutectic alloy was undercooled by the melt fluxing technique and the microstructure was characterized by the back-scattering diffraction technique. A transition from hypereutectic to hypoeutectic was found at a critical undercooling of Δ T  = 119 K. When Δ T  < 119 K, a primary directional dendritic β -Co 3 B phase surrounded by the regular α -Co +  β -Co 3 B lamellar eutectics was found. When Δ T  > 119 K, the above hypereutectic microstructure changes into hypoeutectic structure with the α -Co phase as the primary phase. According to dendrite growth model, the transition from hypereutectic to hypoeutectic can be ascribed to the higher growth velocity of the α -Co phase than the β -Co 3 B phase, i.e., the growth-controlled mechanism. The current work shows also that there is a coupled zone skewed to the β -Co 3 B phase in the Co-B alloys system. [ABSTRACT FROM AUTHOR]

Phase compositions of B-Fe-Mn-V alloys were studied by several experimental methods (DTA measurement, X-ray diffractions, and scanning electron microscopy). Besides the experimental study of the quaternary system, thermodynamic modelling of the ternary B-Mn-V system by the Calphad method and thermodynamic calculations for the quaternary B-Fe-Mn-V system were performed. Calculations for the quaternary system are based on the ternary subsystems (B-Mn-V, B-Fe-V, B-Fe-Mn, and Fe-Mn-V). Boron is modelled as an interstitial element in all solid solutions of vanadium, manganese, and iron. Very good agreement between experimental results and thermodynamic calculations was achieved. The created thermodynamic database is suitable for thermodynamic calculations of phase diagrams for all the ternary subsystems and also for the B-Fe-Mn-V quaternary system. [ABSTRACT FROM AUTHOR]

Mo-Si-B alloys were obtained by spark plasma sintering (SPS) using Mo-57Si-10B and Mo-52Si-15B alloy powders, and the effects of the B content and powder size on the isothermal and cyclic oxidation behaviours of the Mo-Si-B alloys at 1250 °C were investigated. A SiO 2 phase was introduced during the SPS process and the Mo-Si-B alloys consisted of a fine MoSi 2 /Mo 2 B 5 /MoB/SiO 2 microstructure. Under isothermal and cyclic oxidation conditions, the kinetic curves of the SPS Mo-Si-B alloys exhibited parabolic time dependence on the weight gain. The increase in the nominal B caused a decrease in the incubation stage of the formation of continuously protective borosilicate layer but increased the mass gain due to the higher fluidity of the borosilicate layer. The SiO 2 phase was found to supply the borosilicate layer with a “Mechanical locking” mechanism through the spilling of the SiO 2 phase in the SPS samples, especially under the cyclic oxidation condition. [ABSTRACT FROM AUTHOR]

In this study, the effect on microstructure, hardness and slurry erosion wear of alloyed ductile iron (DI) with addition of 0.019 % of Niobium and 0.145 % of Vanadium before and after boronizing process will be discussed. The specimens of ductile iron (DI) and Nb-V alloyed DI were produced through CO2 sand casting method. Specimens were fully coated with boronizing paste in estimation about 3-5mm thickness and heated using Carbolite furnace at 850 °C and 900 °C for 8 hours holding time. The observations of Microstructures were conducted by using Olympus BX 41M Optical Microscope. Vickers Micro Hardness Tester was used to determine the hardness of the specimens while Slurry erosion wear test was conducted to measure the weight loss of each specimen. Diffusing boron into the iron crystalline lattice leads to the formation of two kinds of iron borides (FeB and Fe2B). The thickest boride layer was detected at sample with temperature of 900 °C. The samples of 900 °C give higher hardness than temperature of 850 °C which are 2500 HV and 2209 HV respectively. Referring to slurry erosion test, samples boronized at 900 °C had greater wear resistance compared to sample boronized at 850 °C and as cast. This was attributed by the value of weight losses and surface roughness for the materials. This study had proven that, by increasing the boronizing temperature from 850 °C to 900 °C at 8 hours holding time has a significance effect to the boride layer thickness, hardness and wear resistance of alloyed ductile iron. [ABSTRACT FROM AUTHOR]

Boron and praseodymium doped bismuth oxide nanocomposites were prepared through polymeric precursor technique. The nanocomposites were then sintered to identify the changes in the microstructures of the nanocomposites. The microstructural properties of the nanocomposites were investigated by means of Brunauer-Emmett-Teller nitrogen adsorption, a Scanning Electron Microscope, a Fourier Transform Infrared Spectrometer, and an X-Ray Diffractometer. The Fourier Transform Infrared Spectra of nanocomposites was attested from the presence of boron, praseodymium, and bismuth oxides. According to the X-Ray Diffractometer results, β -bismuth oxide was formed after calcination. Moreover, sintering affected on the crystalline structure of the boron undoped nanocomposite. The sintered boron doped nanocomposite was mainly consisted of the hexagonal bismuth praseodymium oxide while the β -bismuth oxide phase was dominant for the sintered boron doped nanocomposite. The Scanning Electron Microscope micrographs of the nanocomposites showed the plate-like structures. The surface areas of the nanocomposites were decreased because of sintering in accordance with the Brunauer-Emmett-Teller results. [ABSTRACT FROM AUTHOR]

One of the impediments in the development of thermoelectric devices for power generation is that they mostly contain toxic and expensive elements and/or are synthesized using expensive or time-consuming material processing methodology. We report the synthesis of Silicon–Boron (Si 96 B 4 ) alloy employing earth abundant constituent element using a facile single-step reactive sintering using spark plasma sintering technique. In order to enhance its mechanical properties, the synthesized Si 96 B 4 alloy was dispersed with SiC nanoparticles and the effect of its addition on the thermoelectric and mechanical properties in the resulting Si 96 B 4 /SiC nanocomposite has been investigated. A thermoelectric figure-of-merit ZT ~ 0.27 at 1123 K was realized at an optimized composition of Si 96 B 4 /1 wt% SiC nanocomposite. This enhancement in ZT primarily originates from a noticeable reduction in the thermal conductivity on SiC dispersion in Si 96 B 4 alloy, owing to the scattering of heat-carrying phonons by nanoscale SiC particles and mesoscale SiB 3 precipitates, formed in-situ. The synthesized samples were characterized using X-ray diffraction and field emission scanning electron microscopy, based on which the enhancement in their thermoelectric and mechanical properties are discussed. Considering the low-cost and non-toxicity of the constituent elements coupled with facile and up-scalable one-step processing employed in its synthesis, Si 96 B 4 /SiC nanocomposites could be a potential p-type thermoelectric material for high-temperature power generation applications. [ABSTRACT FROM AUTHOR]

The effect of the addition of boron to the biomedical alloy Ti-13Nb-13Zr (TNZ) has been studied. A noticeable change between TNZ and TNZ-0.5B has been observed both in terms of morphology, and size scale of the α precipitates along with the in situ formation of TiB precipitates during laser processing. These contrasting microstructures are responsible for differences in mechanical hardness and sliding wear properties and mechanisms. [ABSTRACT FROM AUTHOR]