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We have grown and characterized (110)-oriented YBa2Cu3O7−x (YBCO)/PrBa2(Cu0.8Ga0.2)3O7−x (PBCGO) bilayer and YBCO/PBCGO/YBCO trilayer heterostructures, which were deposited by pulsed laser deposition technique for the nanofabrication of (110)-oriented YBCO-based superconductor (S)/insulator (I)/superconductor (S) tunneling vertical geometry Josephson junction and other superconductor electronic devices. The structural properties of these heterostructures, investigated through various x-ray diffraction techniques (profile, x-ray reflectivity, pole figure, and reciprocal mapping), showed (110)-oriented epitaxial growth with a preferred c-axis-in-plane direction for all layers of the heterostructures. The atomic force microscopy measurement on the top surface of the heterostructures showed crack-free and pinhole-free, compact surface morphology with about a few nanometer root mean square roughness over the 5 × 5 μm2 region. The electrical resistivity measurements on the (110)-direction of the heterostructures showed superconducting critical temperature (Tc) values above 77 K and a very small proximity effect due to the interfacial contact of the superconducting YBCO layers with the PBCGO insulating layer. Raman spectroscopy measurements on the heterostructures showed the softening of the Ag-type Raman modes associated with the apical oxygen O(4) and O(2)-O(3)-in-phase vibrations compared to the stand-alone (110)-oriented PBCGO due to the residual stress and additional two Raman modes at ∼600 and ∼285 cm−1 frequencies due to the disorder at the Cu–O chain site of the PBCGO. The growth process and structural, electrical transport, and Raman spectroscopy characterization of (110)-oriented YBCO/PBCGO bilayer and YBCO/PBCGO/YBCO trilayer heterostructures are discussed in detail. [ABSTRACT FROM AUTHOR]

The complex permeability and power losses are very important parameters for soft magnetic materials. In this paper, the temperature dependence of these two parameters is investigated for Mn–Zn ferrite. The Hopkinson peak was observed at 440 K below the Curie temperature (TC), and the domain-wall resonance peaks and the natural resonance peaks gradually move to lower frequencies until the Hopkinson temperature (TH). Further, the domain-wall resonance peaks from relaxation type to resonance type are observed by fitting the permeability spectrum, which is related to the reduction of the loss factor. In addition, the power losses were measured from 245 to 365 K and divided into hysteresis loss (Ph), eddy current loss (Pe), and excess loss (Pexc). Each loss contribution was discussed to be dependent on temperature. The results show that at high temperatures and high frequencies, the thermal superposition effect will cause an abnormal increase in excess loss. [ABSTRACT FROM AUTHOR]

The TMS Board of Directors recently approved professional membership for a diverse group of new members from countries like the United States, Pakistan, Canada, and Zimbabwe, representing institutions ranging from universities to technology companies. This decision underscores TMS's commitment to inclusivity and collaboration within the minerals, metals, and materials science field. The list of new members welcomed in May and August 2024 includes individuals from various countries and institutions, showcasing a global community of researchers and professionals working together in fields like materials science and engineering. The document highlights international collaboration and knowledge exchange among researchers and professionals from countries such as the United States, Japan, Germany, and South Korea, emphasizing the importance of global partnerships in advancing scientific research efforts. [Extracted from the article]

We are entering an era of re-electrification, seeking high-power density electrical machines with minimal resource use. Significant performance gains in electrical machines have been achieved through precise manufacturing processes, including the shaping/cutting of soft magnetic materials. However, most studies have evaluated magnetic performance at a macro level, focusing on components, while the fundamental mechanisms, e.g., how the micromagnetic behaviour is affected by mechanical interference, remain unclear. In this study, we examine the impact of sub-micron deformations at opposing strain rates (10−2 to 101 s−1) on the micromagnetic behaviour of soft magnetic non-oriented electrical steel. Using a diamond probe to indent within a single grain of polycrystalline material at different velocities, we induce quasi-static and dynamic mechanical loading. Our analysis, employing magnetic force microscopy, transmission Kikuchi diffraction, and scanning transmission electron microscopy with a pixelated detector, reveals that magnetic texture disturbances rely on the time-dependent dislocation dynamics of the Fe-BCC material. Additionally, we compress micro-pillars to further investigate these effects under bulk-isolated deformation. These findings highlight the importance of considering even ultra-small loads, such as nano-indentations and micro-pillar compressions, in the manufacturing of next-generation electric machines, as they can affect magnetic texture and performance. Mechanical deformations affect magnetic properties of electrical steels, impacting machine efficiency. Here, authors demonstrate that sub-micron deformations at different strain rates alter micromagnetic behaviour of non-oriented electrical steel due to time-dependent dislocation dynamics. [ABSTRACT FROM AUTHOR]

To investigate the impact of diverse multivariate mixing excitation conditions on the hysteresis loop of ferromagnetic materials, this study initially constructs a magnetic performance testing system for electrical steel. This system is capable of generating mixed excitation utilizing a standard Epstein square‐circle setup. Subsequently, the study measures the magnetic properties of the oriented silicon steel sheets at various mixing AC frequencies of the hysteresis loop data. Secondly, a hybrid network model integrating a convolutional neural network (CNN) and a bi‐directional long short‐term memory network (BiGRU), augmented with an attention mechanism (AM), is proposed and utilized for predicting the hysteresis properties of oriented silicon steel wafers subjected to compound mixed‐frequency excitation. The model utilizes CNN to extract high‐dimensional data features reflecting the hysteresis characteristics of the loop, BiGRU to capture the temporal evolution patterns of the key feature vectors, an AM to weigh the feature parameters and emphasize the key features, and a Bayesian optimization (BO) algorithm based on neural network hyperparameters for automatic selection, enhancing prediction accuracy. In comparison with experimental observations, the method accurately predicts material hysteresis properties under non‐sinusoidal complex excitation conditions, outperforming existing deep‐learning network models. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

In this paper, dynamic anti-plane problem in graded non-homogeneous magnetic-electric-elastic material with a conductive cylindrical rigid inclusion is studied. Cracks are generated from the inclusion edge under the action of SH guided waves. By applying a pair of reversed shear stresses to the crack surface, the mechanical model of the crack is achieved, and Green's function method is used in this process. The scattering fields of displacement, electric potential and magnetic potential are constructed by the wave function expansion method. Numerical results clarified the factors that affect the dynamic stress intensity factor of the crack tips, including material parameters, inclusion parameters, wave number and incident angle. It is expected that the investigation of magnetic-electric-elastic material with inclusion-initiated crack defects can provide some references for the project designing, manufacture and application of non-homogeneous multi-fields coupling materials. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The document discusses the importance of heat treatment in modifying the microstructure of metals to achieve desired properties. It highlights research papers on various heat treatment methods and their effects on different alloys, including bearings, martensitic stainless steel, electrical steels, and high resistance steel. The studies focus on optimizing heat treatment parameters to enhance mechanical and magnetic properties, with implications for industrial applications. The document also presents a method for manufacturing low-cost heat pipes with specific properties and geometry using basic tools and 3D printers. [Extracted from the article]

In this study, how crystallographic texture and changes in microstructure affect the magnetic properties of a semi‐processed non‐oriented (NO) electrical steel, which is investigated in its as‐received state and after heat treatment, is evaluated. Electron backscattered diffraction analysis shows the variation in texture with a crystallographic orientation changing from a predominance of γ and α fibers to a random one after heat treatment, with a significant increase in components with <100> directions in the sheet plane, which are desired for NO steels because they are parallel to the direction of easy magnetization. Heat treatment has also increased the average grain size of the samples from 18 to 128 μm. Magnetic properties are analyzed over a wide frequency range and induction, presenting different behaviors in permeability and magnetic loss for the samples before and after heat treatment. The components of total magnetic loss are also evaluated, and the hysteresis loss of heat‐treated sample decreases significantly. This demonstrates that heat treatment reduces microstructural imperfections, causing a decrease in hysteresis losses. Therefore, it is concluded that the improvement in magnetic performance observed with heat treatment has its origin in the increase in fiber components related to the <100> directions and a decrease in microstructural imperfections. [ABSTRACT FROM AUTHOR]

Density, surface tension, and viscosity of various liquid electrical steels are measured at different temperatures, varying in their silicon content between 3 and 6 mass%. Density and surface tension are determined using the maximum bubble pressure method, while viscosity is investigated comparatively using a vibrating finger viscometer and an oscillating crucible viscometer. The results are compared with models known from the literature. Based on this, the density of the steel [ρ] = kg m−3 and the surface tension [σ] = N m−1 can be described as a function of temperature [θ] = °C and silicon content [Si] = mass% using the equations: ρ(θ,Si)=−1.28×θ−104.18×Si+9081.8, σ(θ,Si)=10−4×[ −0.00903×θ2−1.21494×Si2+29.268×θ−1.987×Si−22334 ]. There is a lack of experimental data in the literature for high‐temperature thermophysical properties for electrical steels. This underlines once again the novelty and significance of this study, as the determined thermophysical properties are essential for a wide range of applications. For instance, they are crucial in the production of metallic powders for additive manufacturing by atomization to adjust the properties of the powders precisely. The findings are also important for steelmaking itself, as the corrosion behavior of refractory material can be better determined. [ABSTRACT FROM AUTHOR]

The effects of Si content of steel melts containing 1.5% Al as well as alloying sequence of Si and Al on the evolution of inclusions are investigated. The SiO2 inclusion is primarily formed when Si (=0.5–3.0 wt%) is added to the melts at 1873 K, and the area fraction (AF) of the inclusions decreases over time. The subsequent addition of 1.5% Al to the Si‐alloyed steel (i.e., 3.0Si→1.5Al) increases the AF of inclusions due to the formation of Al2O3. The population density function (PDF) analysis for the preferential Si alloying shows a fractal distribution, indicating that the inclusions grow by a collision mechanism. PDF analysis shows a lognormal distribution because Al2O3 inclusion is formed and grows after subsequent Al alloying. Alternatively, when 1.5% Al is preferentially added to steel, Al2O3 clusters are formed. The AF of Al2O3 cluster decreases over time. When 3.0% Si is subsequently added to the Al‐alloyed steel (i.e., 1.5Al→3.0Si), singular Al2O3 particles are mainly observed. Because the Al alloying results in the formation of Al2O3 regardless of the alloying sequence and Si content, it is important to float up and separate Al2O3 cluster to improve the cleanliness of high‐Si‐Al‐alloyed steels such as electrical steels. [ABSTRACT FROM AUTHOR]

The present study reports the synthesis of cobalt ferrite nanoparticles (CoFe 2 O 4 NPs) using the sol-gel precipitation process via mixing a stoichiometric ratio of cobalt chloride (1 M) and ferric chloride (2 M). The molar of ferric to cobalt was mentioned (2:1) and then 2 M of sodium hydroxide was added. The structural and morphological features of the material were assessed using X-ray diffraction (XRD), Scanning electron microscopy (SEM), and atomic force microscopy (AFM). The electrical properties were analyzed using an LCR meter, while the magnetic properties were measured using a vibrating sample magnetometer (VSM). Fourier-transform infrared spectroscopy (FTIR) investigated the material's molecular vibrations. The X-ray diffraction (XRD) analysis revealed that all the samples exhibited a cubic spinal structure, and no additional peak was detected. Interestingly, the average size of the crystallites (D) decreased from 17.74 nm to 16.58 nm as the pH level increased from 7 to 13. This finding provides important insights into the behaviour of the tested samples under different pH conditions. The formation of the ferrite spine was confirmed by FTIR spectroscopy, with the primary detected bands (408.92–470.65 cm−1) attributed to the octahedral complexes and (516.94–588.31 cm−1) assigned to the tetrahedral ones. The dielectric and imaginary part of the dielectric constant decreased with increasing pH values excluding samples prepared at pH = 11. All samples with different pH values exhibit resonance peaks at frequencies up to (1 KHz). The magnetic measurements carried out by the VSM instrument, the result show that the saturation magnetization increases with increasing pH and the higher saturation magnetization is 68 emu. g1. [ABSTRACT FROM AUTHOR]

This paper explores the effects and impacts of the metallurgical process of quenching on grain-oriented strips of electrical steel. Experimental findings reveal that quenching resulted in increased hardness and an increased Young's modulus. An analysis of the material structure post-quenching indicates significant alterations in grain spacing and reduced height differences between grains. However, the magnetic properties of the steel deteriorated following quenching. [ABSTRACT FROM AUTHOR]

The production of grain-oriented, electrical steel consists of a series of processes that lead to a product with superior magnetic properties used in transformers due to the low core loss. The unique properties are gained during the process of secondary recrystallization and abnormal grain growth. The abnormal grain growth occurs during a process of special thermal treatment with careful control over the heating rate, pressure, and type of gas used as atmospheric pressure during the process. The process of thermal treatment is known as high-temperature annealing. Investigating of developing the process hardware is crucially important to sustain energy-efficient processes and to maintain excellent final product properties. This research presents an overview of the technology of high-temperature coil annealing (HTCA) furnaces used at Cogent Power Orb, UK. The research focuses on some specific details of running, managing, and controlling the operation of the HTCA furnaces during the annealing process. The research provides energy analysis of the annealing process at Cogent Power Orb. Different factors were examined to identify the main factors that contribute to the high energy consumption. Actual data were collected from the annealing furnace control system. The raw data were processed and analyzed carefully to examine different factors, namely, steel charge weight, furnace on-time, and furnace heating elements. The study focused then on one specific factor, namely, annealing cycle time, and investigated further the way that this factor affects the process energy consumption. It was found that one of the main reasons for the long cycle duration and the high energy consumption is the failure of the heating elements during the cycle. The research discussed the area of improvements in the process hardware with a particular focus on the furnace design and the potential of introducing convection currents to overcome failure in the heating elements and thus reduce the process on time.

Hot rolling is a critical thermomechanical processing step for nonoriented electrical steel (NOES) to achieve optimal mechanical and magnetic properties. Depending on the silicon and carbon contents, the electrical steel may or may not undergo austenite–ferrite phase transformation during hot rolling, which requires different process controls as the austenite and ferrite show different flow stresses at high temperatures. Herein, the high‐temperature flow behaviors of two nonoriented electrical steels with silicon contents of 1.3 and 3.2 wt% are investigated through hot compression tests. The hot deformation temperature is varied from 850 to 1050 °C, and the strain rate is differentiated from 0.01 to 1.0 s−1. The measured stress‐strain data are fitted using various constitutive models (combined with optimization techniques), namely, Johnson–Cook, modified Johnson–Cook, Zener–Hollomon, Hensel–Spittel, modified Hensel–Spittel, and modified Zerilli–Armstrong. The results are also compared with a model based on deep neural network (DNN). It is shown that the Hensel–Spittel model results in the smallest average absolute relative error among all the constitutive models, and the DNN model can perfectly track almost all the experimental flow stresses over the entire ranges of temperature, strain rate, and strain. [ABSTRACT FROM AUTHOR]

To examine the effect of mixed-frequency excitation conditions on the hysteresis and loss characteristics of ferromagnetic materials, this paper shows how to construct magnetic property test equipment for electrical steel using Epstein's square circle. Experiments were carried out to assess the hysteresis and loss properties of oriented silicon steel wafers under mixed-frequency sinusoidal operating conditions with different occupancy ratios. It used heterodyne extraction to investigate the effect of different occupancy ratios of industry and magnetization frequency on the hysteresis and loss characteristics of oriented silicon steel sheets. [ABSTRACT FROM AUTHOR]

Currently, many utility‐scale wind turbine generator original equipment manufacturers are dependent on imported rare earth permanent magnets, which are susceptible to market risks from cost instability. To lower the production costs of these generators and stay competitive in the market, several small wind manufacturers are pursuing continuous improvements to both generator design and manufacturing. However, traditional design and manufacturing methods have yielded marginal improvements in wind power performance. This work presents novel methods to redesign a baseline 15‐kW wind turbine generator with reduced rare‐earth permanent magnets by leveraging cutting‐edge three‐dimensional (3D) printed polymer‐bonded permanent magnets and steel. Symmetric, asymmetric, and multimaterial‐magnet parametrization methods are introduced for shape optimization. We extend the symmetric and asymmetric methods to the back iron in the stator to further investigate the impact and opportunities for performance improvements with lesser active materials. We employ a design‐of‐experiments approach with parametric computer‐aided design for shape generation and evaluate different designs by magneto‐thermal modeling and finite‐element analysis. We use adaptive sampling technique to identify better performing designs with lesser magnet mass, higher efficiency, and lower cogging torque when compared with the baseline generator. Asymmetric pole designs resulted in a magnet mass in the range of 4.77–5.37 kg, which was 27%–35% lighter than the baseline generator, suggesting that a new design freedom exists that can be enabled by advanced manufacturing, such as 3D printing. Shaping the back iron in the stator resulted in material savings in electrical steel of up to 14.62 kg, which was 20% lighter than the baseline stator. We conducted a structural analysis to evaluate an optimized asymmetric rotor design from the point of view of mechanical integrity and air‐gap stiffness. The magnetically optimal shape profile was shown as having a positive impact on the radial stiffness, and an optimal solution was discovered to reduce the structural mass by nearly 30 kg, which was 29% lighter than the baseline. [ABSTRACT FROM AUTHOR]

At present, almost 50% of electrical power is consumed by motors. Thus, increasing the efficiency of motors is an important issue. To achieve more efficient operation, it is vital to improve the accuracy of input data for motor loss design. In this study, we focused on the iron loss of electromagnetic steels, which is assumed to account for a large proportion of motor losses, and examined whether the effect of stress on the iron loss and its frequency dependence could be predicted with high accuracy by machine learning. First, experimental iron loss data are obtained at flux densities of 0.1-1.7 T, frequencies of 50-3000 Hz, and applied stresses from 200 to 200 MPa. No significant deterioration in iron loss behavior is observed in specimens subjected to 3% and 10% pre-strain by tensile loading. These data show that the effect of stress on iron loss varies significantly depending on the excitation conditions. The complex iron loss behaviors are the result of interplay between magnetic wall movement and magnetic domain rotation during the magnetization process. As simple regression of the magnetization process is difficult, we apply three machine learning algorithms to the experimental dataset. The results show that the LightGBM algorithm produces the most accurate predictions of the experimental iron loss values. The contributions of the explanatory variables are found to be consistent with empirical knowledge. This study demonstrates the potential for machine learning to enable improve the accuracy of iron loss data input to motor loss design. [ABSTRACT FROM AUTHOR]

Effect of annealing stresses on the magnetic properties of non-oriented electrical steel has been studied. When the annealing stress increases from 2.5 to 4.5 MPa, the iron loss P1.0/400 of non-oriented electrical steel increases from 14.28 to 15.29 W/kg, the anisotropy index T raises from 17.0 to 22.0 pct, the magnetic induction B5000 decreases from 1.656 to 1.646 T. This is mainly due to the amount of MnS-containing precipitates increases with the increasing of the annealing stress. [ABSTRACT FROM AUTHOR]

Nonoriented electrical steel for new energy vehicles should have high strength and excellent magnetic properties simultaneously. However, it is challenging to optimize mechanical and magnetic properties simultaneously during nonoriented electrical steel processing. This article prepares nonoriented electrical steel with high strength and excellent magnetic properties by Cu–Ni alloying, and the evolution of properties of Cu–Ni‐alloyed nonoriented electrical steel during aging and underlining mechanisms is studied. The optimal strength is achieved when aging for 10 min with a yield strength of 773 MPa, where the magnetic induction intensity (B50) is 1.66 T, and the iron loss (P1.0/400) is 18.07 W Kg−1. The optimal strength is attributed to the Cu–Ni recombination, which induces a rapid precipitation of numerous small‐sized Cu‐rich phases within a short period. Besides, the main strengthening mechanisms of the small‐size Cu‐rich phases are modulus strengthening and ordered strengthening. Furthermore, the small‐size Cu‐rich phases with B2 and body‐centered cubic structure in the earlier aging period do not deteriorate the magnetic properties of the steel. Nevertheless, in the late aging period, due to the coarsening of the precipitated Cu‐rich phase with face‐centered cubic structure and the abnormal growth of some grains, the eddy current loss increases, leading to worsen magnetic properties. [ABSTRACT FROM AUTHOR]

Among soft magnetic materials, non-grain-oriented electrical steel (NGOES) has emerged as a promising option for various applications. NGOES material plays a crucial role across the entire energy value chain, spanning from power generation through generators to the consumption of electrical energy in electric motors and appliances within the electrical components industry which can lead to a notable enhancement in the performance of electric motors. NGOES are widely used for soft magnetic applications due to their cost and also their superior magnetic properties, including high electrical resistivity, excellent saturation magnetization, and minimal magnetostriction. NGOES are anticipated to serve as a driving force in the future global market for electric power consumption. The magnetic properties of NGOES are profoundly influenced by metallurgical factors such as Si content, grain size, crystallographic texture, sheet thickness, and surface roughness. These crucial variables play a crucial role in shaping the magnetic characteristics of NGOES materials which will be covered in this review paper. This paper provides an overview of different manufacturing routes for NGOES, as well as the advantages and disadvantages of these processes. Moreover, alternative manufacturing techniques and their capability to optimize the microstructure and to fabricate high Si NGOES sheets are discussed. Also, it addresses the challenges associated with mass-producing materials with high Si content using traditional methods. These advancements in this area present promising opportunities for enhancing the manufacturing processes of NGOES and ultimately enhancing the performance of future electrical machines and generators. [ABSTRACT FROM AUTHOR]

This study investigates the viscosity, density, surface tension, and crystallization behavior of two commercial mold fluxes that are utilized to cast ultralow‐carbon, low‐carbon, and medium‐carbon steel grades, as well as electric steels (high‐B magnetic and grain‐oriented steels). Experiments are performed in the temperature range of 1073–1673 K using the rotating bob method, maximum bubble pressure method, buoyancy method, and single hot thermocouple technique. The phase structure is investigated via scanning electron microscopy and X‐ray powder diffraction. The results indicate that viscosity and density exhibit nonlinear temperature dependence. Increased basicity (CaO/SiO2) results in reduced viscosity and elevates the break temperature of the mold fluxes. Furthermore, the incubation time required for phase formation decreases with increasing basicity. Finally, time–temperature transformation and continuous cooling transformation diagrams are constructed. [ABSTRACT FROM AUTHOR]

Flexible graphite foils with varying thicknesses (S = 282 ± 5 μm, M = 494 ± 7 μm, L = 746 ± 8 μm) and an initial density of 0.70 g/cm3 were obtained using the nitrate method. The specific electrical and thermal conductivity of these foils were investigated. As the density increased from 0.70 g/cm3 to 1.75 g/cm3, the specific electrical conductivity increased from 69 to 192 kS/m and the thermal conductivity increased from 109 to 326 W/(m·K) due to the rolling of graphite foils. The study showed that conductivity and anisotropy depend on the shape, orientation, and contact area of thermally expanded graphite (TEG) mesoparticles (mesostructural factor), and the crystal structure of nanocrystallites (nanostructural factor). A proposed mesostructural model explained these increases, with denser foils showing elongated, narrowed TEG particles and larger contact areas, confirmed by electron microscopy results. For graphite foils 200 and 750 μm thick, increased density led to a larger coherent scattering region, likely due to the rotation of graphite mesoparticles under mechanical action, while thinner foils (<200 μm) with densities > 1.7 g/cm3 showed increased plastic deformation, indicated by a sharp reduction in the coherent scattering region size. This was also evident from the decrease in misorientation angles with increasing density. Rolling reduced nanocrystallite misorientation angles along the rolling direction compared to the transverse direction (TD) (for 1.75 g/cm3 density ΔMA = 1.2° (S), 2.6° (M), and 2.4° (L)), explaining the observed anisotropy in the electrical and mechanical properties of the rolled graphite foils. X-ray analysis confirmed the preferred nanocrystallite orientation and anisotropy coefficients (A) using Kearns parameters, which aligned well with experimental measurements (for L series foils calculated as: A0.70 = 1.05, A1.30 = 1.10, and A1.75 = 1.16). These calculated values corresponded well with the experimental measurements of specific electrical conductivity, where the anisotropy coefficient changed from 1.00 to 1.16 and mechanical properties varied from 0.98 to 1.13. [ABSTRACT FROM AUTHOR]

The paper focuses on an extension of the GRUCAD hysteresis model. The extension relies on the re- placement of the Langevin function with a more general Brillouin function in an equation describing the anhysteretic curve. The proposed approach allows one to obtain better fitting capabilities for anisotropic soft magnetic materials, as demonstrated by the example of hysteresis curves of grain-oriented electrical steel. [ABSTRACT FROM AUTHOR]

This paper focuses on two models used for the determination of power loss components in steel samples under dynamic magnetizing conditions. The considered models differ in their approach as far as the possibility of distinguishing bulk and localized eddy currents is concerned. Two samples of non-oriented electrical steel differing in silicon weight contents are the subject of experiments. A comparison of the obtained results, as well as their discussion, is given in the paper. [ABSTRACT FROM AUTHOR]

The widespread adoption of aluminumalloy electric buses, known for their energy efficiency and eco-friendliness, faces a challenge due to the aluminum frame's susceptibility to deformation compared to steel. This issue is further exacerbated by the stringent requirements imposed by the flammability and explosiveness of batteries, necessitating robust frame protection. Our study aims to optimize the connectors of aluminum alloy bus frames, emphasizing durability, energy efficiency, and safety. This research delves into Multi-Objective Coordinated Optimization (MCO) techniques for lightweight design in aluminum alloy bus body connectors. Our goal is to enhance lightweighting, reinforce energy absorption, and improve deformation resistance in connector components. Three typical aluminum alloy connectors were selected and a design optimization platform was built for their MCO using a variety of software and methods. Firstly, through three-point bending experiments and finite element analysis on three types of connector components, we identified optimized design parameters based on deformation patterns. Then, employing Optimal Latin hypercube design (OLHD), parametric modeling, and neural network approximation, we developed high-precision approximate models for the design parameters of each connector component, targeting energy absorption, mass, and logarithmic strain. Lastly, utilizing the Archive-based Micro Genetic Algorithm (AMGA),Multi-Objective Particle Swarm Optimization (MOPSO), and Non-dominated SortingGenetic Algorithm(NSGA2),we explored optimized design solutions for these joint components. Subsequently, we simulated joint assembly buckling during bus rollover crash scenarios to verify and analyze the optimized solutions in three-point bending simulations. Each joint component showcased a remarkable 30%--40% mass reduction while boosting energy absorption. Our design optimization method exhibits high efficiency and costeffectiveness. Leveraging contemporary automation technology, the design optimization platformdeveloped in this study is poised to facilitate intelligent optimization of lightweight metal components in future applications. [ABSTRACT FROM AUTHOR]

This study is devoted to the effect of alloying high-permeable electrical anisotropic steel with tin and chromium highly permeable electrical anisotropic steel with tin and chromium on the kinetics of primary recrystallization. The physical modeling of strongly deformed alloy specimens of different chemical composition is performed. The obtained recrystallization kinetics equations for alloys of different tin and chromium content show a deceleration of recrystallization process in a steel with an increased tin content and a decreased chromium content. Analysis of the texture at different stages of recrystallization allows making conclusion that the texture is formed predominately by oriented growth. [ABSTRACT FROM AUTHOR]

Nonreciprocal quantum transport effect is mainly governed by the symmetry breaking of the material systems and is gaining extensive attention in condensed matter physics. Realizing electrical switching of the polarity of the nonreciprocal transport without external magnetic field is essential to the development of nonreciprocal quantum devices. However, electrical switching of superconducting nonreciprocity remains yet to be achieved. Here, we report the observation of field-free electrical switching of nonreciprocal Ising superconductivity in Fe3GeTe2/NbSe2 van der Waals (vdW) heterostructure. By taking advantage of this electrically switchable superconducting nonreciprocity, we demonstrate a proof-of-concept nonreciprocal quantum neuronal transistor, which allows for implementing the XOR logic gate and faithfully emulating biological functionality of a cortical neuron in the brain. Our work provides a promising pathway to realize field-free and electrically switchable nonreciprocity of quantum transport and demonstrate its potential in exploring neuromorphic quantum devices with both functionality and performance beyond the traditional devices. The authors demonstrate magnetic-field-free electric switching of superconducting nonreciprocity in Fe3GeTe2/NbSe2 heterostructures. They apply this to propose and demonstrate a proof-of-concept "neural transistor", a tetrode device that realizes an XOR gate with only a single transistor. [ABSTRACT FROM AUTHOR]

The electric vehicle (EV) industry challenges battery joining technologies by requiring higher energy density both by mass and volume. Improving the energy density via new battery chemistry would be the holy grail but is seriously hindered and progresses slowly. In the meantime, alternative ways, such as implementing more efficient cell packaging by minimising the electrical resistance of joints, are of primary focus. In this paper, we discuss the challenges associated with the electrical characterisation of laser-soldered joints in general, and the minimisation of their resistive losses, in particular. In order to assess the impact of joint resistance on the overall resistance of the sample, the alteration in resistance was monitored as a function of voltage probe distance and modelled by finite element simulation. The experimental measurements showed two different regimes: one far from the joint area and another in its vicinity and within the joint cross-section. The presented results confirm the importance of the thickness of the filler material, the effective and total soldered area, and the area and position of the voids within the total soldered area in determining the electrical resistance of joints. [ABSTRACT FROM AUTHOR]

The microstructure and texture evolution of Cu-Ni-P alloy after cold rolling and annealing at 500 °C was studied by electron backscattering diffraction (EBSD). The equiaxed grain is elongated and the dislocation density increases gradually after cold rolling. The grain boundaries become blurred and the structure becomes banded when the reduction in cold rolling reaches 95%. A typical rolling texture is formed with the increase in deformation amount in cold rolling. The deformation structure gradually disappeared and recrystallized new grains were formed after annealing at 500 °C. The recrystallization nucleation mechanism of Cu-Ni-P alloy at 60% reduction is mainly a bow nucleation mechanism. A shear band begins to form after annealing at 80% reduction. The shear band becomes the preferred nucleation location with the increase in reduction. Most adjacent recrystallized grains growing in the shear band have a twin relationship. [ABSTRACT FROM AUTHOR]

This study investigates multiple cyclic loading scenarios of non-oriented electrical steel sheets through both experimental and numerical approaches. The numerical simulations were conducted using Representative Volume Elements generated with DRAGen. DRAGen allowed for the generation of Representative Volume Elements with a non-cubic shape to cover the complete sheet thickness and enough grains to represent the material's texture. The experimental results, on the other hand, are utilized to calibrate and validate a prediction model, highlighting the significance of accumulated plastic slip as a suitable parameter correlated with fatigue life. Using the accumulated plastic slip from the simulations, a fatigue fracture locus is introduced, which describes a 3D surface dependent on the maximum stress, fatigue life, and the fatigue stress ratio. The study shows reliable results for the fatigue life prediction using the calibrated fatigue fracture locus. While substantial progress has been made in predicting the fatigue life at multiple fatigue stress ratios, notable disparities between experimental and simulation results suggest the need for further investigations regarding the influence of the surface quality. This observation motivates ongoing research efforts aimed at refining simulation methodologies to better incorporate surface roughness effects. In summary, this study presents a validated model for predicting fatigue life in non-oriented electrical steel sheets, offering valuable insights into material behavior at different loading scenarios and informing future research directions for enhanced structural performance and durability. [ABSTRACT FROM AUTHOR]

Magnetic skyrmions offer promising prospects for constructing future energy-efficient and high-density information technology, leading to extensive explorations of new skyrmionic materials recently. The topological Hall effect has been widely adopted as a distinctive marker of skyrmion emergence. Alternately, here we propose a novel signature of skyrmion state by quantitatively investigating the magnetoresistance (MR) induced by skyrmionic bubbles in CeMn2Ge2. An intriguing finding was revealed: the anomalous MR measured at different temperatures can be normalized into a single curve, regardless of sample thickness. This behavior can be accurately reproduced by the recent chiral spin textures MR model. Further analysis of the MR anomaly allowed us to quantitatively examine the effective magnetic fields of various scattering channels. Remarkably, the analyses, combined with the Lorentz transmission electron microscopy results, indicate that the in-plane scattering channel with triplet exchange interactions predominantly governs the magnetotransport in the Bloch-type skyrmionic bubble state. Our results not only provide insights into the quantum correction on MR induced by skyrmionic bubble phase, but also present an electrical probing method for studying chiral spin texture formation, evolution, and their topological properties, which opens up exciting possibilities for identifying new skyrmionic materials and advancing the methodology for studying chiral spin textures. [ABSTRACT FROM AUTHOR]

As a promising new material, silver thin film has been widely used in modern industry. Magnetron sputtering with a silver target as the source has become a common method to produce silver film. In this research, the sputtering performance of Ag targets in cold rolling state and annealing state was compared and the relationship between the Ag targets and Ag thin films was explored. The results show that annealing at 600 °C after cold rolling to a deformation of 83.33% can effectively increase the texture density of {110} in Ag. Both in the cold rolling state and annealing state, Ag targets exhibited a similar deposition rate. The resistivity of both kinds of Ag thin films decreases with the sputtering time. Ag thin films formed by sputtering Ag targets of two states for the same sputtering time displayed different resistivity, with the annealing state being superior over the rolling state. Ag target in annealing state, owing its uniform microstructure, showed shallower depth of rack track after sputtering. Annealing treatment after cold rolling is an alternative method to improve the target microstructure. [ABSTRACT FROM AUTHOR]

The electrical resistivity of 12Х18Н10Т stainless steel specimens was measured in the course of compression and heating under stepwise shock compression. A mathematical simulation of the obtained experimental data was conducted. The simulation allowed switching to specific values and reconstructing the volume–temperature dependence of the electrical resistivity of steel at high pressures of 25–65 GPa and temperatures of 350–950 K. Semi-empirical regularities were identified that permit the prediction of the total effect of a decrease in the electrical resistivity of 12Х18Н10Т steel upon compression and its increase upon heating. The outcomes of the electrical resistivity tests on shock-compressed and heated steel are evaluated in comparison with the existing literature data on similar experiments conducted under atmospheric pressure and high temperatures. [ABSTRACT FROM AUTHOR]

Surface modification through electrical discharge machining (EDM) results in many advantages, such as improved surface hardness, enhanced wear resistance, and better micro-structuring. During EDM-based surface modification, either the eroding tool electrode or a powder-mixed dielectric can be utilized to add material onto the machined surface of the workpiece. The current study looks at the surface modification of H13 die steel using EDM in a dielectric medium mixed with graphite powder. The experiments were carried out using a Taguchi experimental design. In this work, peak current, pulse-on time, and powder concentration are taken into consideration as input factors. Tool wear rate (TWR), material removal rate (MRR), and the microhardness of the surface of the machined specimen are taken as output parameters. The machined surface's microhardness was found to have improved by 159%. The results of X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS) analysis and changes in MRR and TWR due to the powder-mixed dielectric are also discussed in detail. [ABSTRACT FROM AUTHOR]

〈001〉//ND (normal direction) texture (including the cube, {001}〈100〉) is a desired final texture in non-oriented electrical steel (NOES) due to the alignment of two magnetically easy 〈100〉 axes in the magnetization directions of the lamination core in rotating machines. However, after conventional rolling and annealing, the final texture of NOES is usually not the desired 〈001〉//ND texture, but the unfavorable 〈111〉//ND (γ-fiber), 〈110〉//RD (rolling direction) (α-fiber), and sometimes {1 1 h}〈1 2 1/h〉 (α*-fiber) textures. How do these textures (especially the α*-fiber texture) form in the recrystallization process is still not completely understood. This paper investigates the recrystallization process of a warm rolled NOES containing 6.5 wt pct Si and tracks the growth of individual grains using a quasi in-situ EBSD (electron backscatter diffraction) technique. It is shown that the {1 1 h}〈1 2 1/h〉 (α*-fiber) grains (including {001}〈120〉, {114}〈481〉, and {112}〈241〉) normally form in the later stage of recrystallization, and mainly nucleate in the mid-thickness region of the deformed steel from grains having the 〈110〉//RD (α-fiber) orientations. Once nucleated, they can rapidly grow into the deformed matrix due to the large energy difference between the recrystallized and deformed grains and to the high-mobility grain boundaries with respect to the deformed matrix. On the other hand, although cube grains nucleate early during recrystallization, they cannot grow significantly into the deformed grains because of the very high misorientation angles with respect to the deformed grains, which may have caused "orientation pinning". As a result, the cube grains are finally consumed by the large α*-fiber grains due to size disadvantage. The origins of the α*-fiber grains and cube grains are also analyzed using the quasi in-situ EBSD data obtained in the early stages of annealing. [ABSTRACT FROM AUTHOR]

Ferroelectric (Hf,Zr)O2 thin films have attracted increased interest from the ferroelectrics community and the semiconductor industry due to their ability to exhibit ferroelectricity at nanoscale dimensions. The properties and performance of the ferroelectric (Hf,Zr)O2 films generally depend on various factors such as surface energy (e.g., through grain size or thickness), defects (e.g., through dopants, oxygen vacancies, or impurities), electrodes, interface quality, and preferred crystallographic orientation (also known as crystallographic texture or simply texture) of grains and/or domains. Although some factors affecting properties and performance have been studied extensively, the effects of texture on the material properties are still not understood. Here, the influence of texture of the bottom electrode and Hf0.5Zr0.5O2 (HZO) films on properties and performance is reported. The uniqueness of this work is the use of a consistent deposition process known as Sequential, No-Atmosphere Processing (SNAP) that produces films with different preferred orientations yet minimal other differences. The results shown in this study provide both new insight on the importance of the bottom electrode texture and new fundamental processing-structure–property relationships for the HZO films. [ABSTRACT FROM AUTHOR]

Ferroelectric (Hf,Zr)O2 thin films have attracted increased interest from the ferroelectrics community and the semiconductor industry due to their ability to exhibit ferroelectricity at nanoscale dimensions. The properties and performance of the ferroelectric (Hf,Zr)O2 films generally depend on various factors such as surface energy (e.g., through grain size or thickness), defects (e.g., through dopants, oxygen vacancies, or impurities), electrodes, interface quality, and preferred crystallographic orientation (also known as crystallographic texture or simply texture) of grains and/or domains. Although some factors affecting properties and performance have been studied extensively, the effects of texture on the material properties are still not understood. Here, the influence of texture of the bottom electrode and Hf0.5Zr0.5O2 (HZO) films on properties and performance is reported. The uniqueness of this work is the use of a consistent deposition process known as Sequential, No-Atmosphere Processing (SNAP) that produces films with different preferred orientations yet minimal other differences. The results shown in this study provide both new insight on the importance of the bottom electrode texture and new fundamental processing-structure–property relationships for the HZO films. [ABSTRACT FROM AUTHOR]

Electrical steels are numerously used in engineering applications. Nowadays, future challenges related to climate change and e-mobility push the boundaries to higher efficiency also in electrical parts. A promising material group to reduce electrical losses are electrical steels with high silicon contents. However, such steels are difficult to process with conventional methods and, thus, additive manufacturing came into focus in recent years. The present study investigates the processability, crack sensitivity, microstructure evolution and magnetic domain structures of laser powder bed fused Fe–Si alloys with 3 and 9 wt.-% Si. It is shown that specimens, which are built using appropriate process parameters, are dense and free of cracks. Still, Fe–9Si is characterized by a higher crack susceptibility at low temperatures of the build platform. A checkerboard like microstructure with elongated grains alongside build direction evolved. Global magnetic properties from ring core measurements showed lower losses for the Fe–9Si ring. Moreover, it was found that the magnetic domain structures are directly influenced by the crystallographic orientations present in the specimen volumes. The findings elaborated will contribute to advanced possibilities in tailoring the magnetic properties of electrical steels for an increase of the efficiency of envisaged applications.

Production of a thin cold rolled sheet of high silicon electrical steel is industrially challenging as it is associated with the formation of different types of cracks. The present study investigates the role of microstructure, crystallographic texture, and analytical stress state on the formation of alligator crack and edge crack during cold rolling of Fe-3.78 wt. % Si electrical steel. Owing to high strain incompatibility, alligator crack initiates from shear bands, which develops during cold rolling. Furthermore, the large difference in Taylor factors of {111}⟨110⟩ and {001}⟨110⟩ oriented grains assisted the crack to follow the hot band interface. Stress analysis based on the finite element method indicates that minor tensile stress in the normal direction develops during the exit stage of cold rolling. This tensile stress has been found to be sufficient to cause cleavage fracture during the last step of alligatoring. The crack propagation is assisted by the large size and favorable orientation of θ-fiber (ND||⟨001⟩) textured grains. On the other hand, the finite element method-based analysis suggests that high tensile stress at the edges during steady state condition initiates the cleavage edge crack, which propagates inward along the transverse direction during the final exit stage. Intermediate annealing and hot band annealing were found to be effective in eliminating the formation of alligator crack and edge crack, respectively. [ABSTRACT FROM AUTHOR]

To investigate the dynamic recrystallization (DRX) behavior of forged 42CrMoA steel during hot deformation, the hot deformation experiments of forged 42CrMoA steel under different deformation conditions (strain rate, temperature, and strain) were carried out in this paper. The hot deformation activation energy of forged 42CrMoA steel was determined to be 413627.2 J · mol - 1 . The constitutive model and DRX kinetic model of the steel were established. Analyzing the reconstructed parent phase grains reveals that when the strain is constant, as the deformation temperature increases and the strain rate decreases, the average size and DRX volume fraction of the parent phase grains gradually increase, and the peak stress gradually decreases. When the deformation temperature and strain rate are constant, as the strain increases, the average size of the parent phase grains gradually decreases, and the volume fraction of DRX gradually increases. Based on the cellular automaton theory model and considering the influence of grain deformation on the DRX process, a cellular automaton dynamic recrystallization (T-DRX-CA) model for forged 42CrMoA steel based on topological deformation technology was established, and the microstructure evolution under different deformation conditions was simulated. The microstructure evolution under different deformation conditions was simulated, which was compared with experimental results. The results showed that the average errors between the simulated and experimental values of the average grain size of the parent phase, the volume fraction of DRX, and peak stress were all less than 8%, and the simulated results were in good agreement with the experimental values, which indicates that the established model can accurately predict the DRX behavior of the forged 42CrMoA steel in the process of hot deformation. The hot deformation behavior of forged 42CrMoA steel under different deformation conditions was investigated by a cellular automaton dynamic recrystallization (T-DRX-CA) model based on topological deformation technique. The results showed that the average errors between the simulated and experimental values of the average grain size of the parent phase, the volume fraction of DRX, and peak stress were all less than 8%, and the simulated results were in good agreement with the experimental values, which indicates that the established model can accurately predict the DRX behavior of the forged 42CrMoA steel in the process of hot deformation. [ABSTRACT FROM AUTHOR]

We are interested in the determination of the local nonlinear magnetic material behaviour in electrical steel sheets due to cutting and punching effects. For this purpose, the inverse problem has to be solved, where the objective function, which penalises the difference between the measured and the simulated magnetic flux density, has to be minimised under a constraint defined according to the corresponding partial differential equation model. We use the adjoint method to efficiently obtain the gradients of the objective function with respect to the material parameters. The optimisation algorithm is low-memory Broyden–Fletcher–Goldfarb–Shanno (BFGS), the forward and adjoint formulations are solved using the finite element (FE) method and the ill-posedness is handled via Tikhonov regularisation, in combination with the discrepancy principle. Realistic numerical case studies show promising results. [ABSTRACT FROM AUTHOR]