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Because the nanocrystalline core is widely used in power electronic equipment, and the excitation waveform of its working mode is complex, the vibration at medium and high frequencies cannot be ignored. Therefore, this study aims to study the vibration mechanism of nanocrystalline strip and the vibration characteristics of nanocrystalline magnetic ring under different excitation waveforms.

First, the electromagnetic vibration mechanism between nanocrystalline strips is analyzed by finite element analysis, and the force of the magnetic ring with and without air gap is compared and analyzed. Then, the vibration of nanocrystalline magnetic ring under different excitation waveforms such as sine wave, triangular wave, symmetric rectangular wave and asymmetric rectangular wave is analyzed by experimental method. The acceleration time domain waveform measured by the experiment is analyzed by fast Fourier transform, and the vibration is analyzed according to the spectrum.

Because of the increase of magnetic flux leakage, the volume force density and the Maxwell force on the surface of the nanocrystalline magnetic ring will increase after the air gap is opened, resulting in the intensification of vibration. Under symmetric/asymmetric rectangular wave excitation, the vibration acceleration varies with the duty cycle. Due to the influence of harmonic excitation, the relationship between the main frequency of vibration and the excitation frequency is not two times, and its multiple decreases with the increase of excitation frequency.

The research and analysis of this paper can promote the application of new magnetic materials in electrical equipment in small and medium-sized and medium- to high-frequency fields.

The purpose of this paper is to present a ribbons production route of composition Fe₇₈Si₉B₁₃ (%at.) using low cost noncommercial scrap materials to obtain usable magnetic cores by melt spinning technique and their characterization. This way, these may compete with the materials produced by conventional casting processes.

The methodology is to design a master alloy with scrap different starting compositions, to which Fe is added to get the desired atomic ratio of components. With this starting alloy, using the method of melt spinning, in its variant of chill block melt spinning, are achieved amorphous ribbons with desired soft magnetic behavior. Then these ribbons are thermally treated for achieve nanocrystalline structures to improve the performance in the magnetic cores.

The result of this paper shows that it is possible to recycle scrap materials, and re-used efficiently as components essential in part of electrical components. This way, these may compete with the materials produced by conventional casting processes.

The limitation of this work to ensure that the scrap materials used is reasonably adequate to accomplish obtaining the master alloy, i.e. having reduced impurities.

The implications are important, because it assures that the components are recyclable and also high-tech in reference to energy saving that involves the production of amorphous and nanocrystalline materials in the electric industry. These products may compete with those produced by conventional casting processes.

The social implications lead to awareness in recycling and energy saving as an option for social progress in technology.

The originality of the study is that it takes as a starting point for the final product (ribbon) noncommercial scrap materials of known composition and the obtained results are comparable to those that also are manufactured from the pure elements. The control of impurities is necessary in the production route. This way, these may compete with the materials produced by conventional casting processes. This process achieved a production with lower cost, high efficient energy products and high added value.

This paper aims to propose a new design for high-power compact solid-state transformers (SSTs) made with grain-oriented electrical steel (GOES) wound cores that benefit from the natural reduction of iron losses at high temperatures.

An experimental approach, coupled with numerical and analytical investigations, is widely used for proving the validity of the proposed concept.

With cores much hotter than coils, the new design of medium frequency transformers can be used for building compact SSTs that rated powers and common-mode insulation voltages much higher than existing ones with similar efficiencies.

The thermal design must provide a large difference between core and coil temperatures in a reasonable volume.

The increasing number of intermittent renewable sources place electric grid stability at risk. Smart nodes, made of SSTs, improve the global grid stability because they are able to provide real-time control of energy fluxes at critical points. In railway applications, high-power SST cells can be distributed along the train providing a larger volume for passengers.

The increasing part of electricity in a flexible grid requires performant and high-power SSTs made with components that have an environmental footprint as low as possible.

This paper proves that the design of high-power transformers with GOES wound cores much hotter than coils is possible. It proposes also a thermal equivalent circuit that helps the design.

This paper aims to investigate magnetic field anneal in micro-patterned Co-based amorphous ribbon on giant magneto-impedance (GMI) effect enhancement.

The amorphous ribbons were annealed in transverse and longitudinal magnetic field. The influence of different field annealing directions on GMI effect and impedance Z, resistance R and reactance X with a series of line width have been deeply analyzed.

In comparison with GMI sensors microfabricated by unannealed and transversal field annealed ribbons, GMI sensor which was designed and microfabricated by longitudinal field anneal ribbon performs better. The results can be explained by the domain wall motion and domain rotation during annealing process and the geometric structure of Co-based GMI sensor. In addition, shrinking the line width of GMI sensor can promote GMI effect significantly because of the effect of demagnetizing field, and the optimum GMI ratio is 209.7 per cent in longitudinal field annealed GMI sensor with 200 μm line width.

In conclusion, annealing in longitudinal magnetic field and decreasing line width can enhance GMI effect in micro-patterned Co-based amorphous ribbon.

The purpose of this paper is to obtain iron‐enriched Fe‐Ni alloy foil on Ti substrates with good quality from a chloride‐sulfate bath used in a normal DC plating mode. The effects of iron content on the hardness, surface morphology and microstructure of the foil were clarified.

Fe‐Ni alloy foil was prepared by electrodeposition in a chloride‐sulfate based solution. The effects of current density, temperature, stirring rate and sodium propargyl sulfonate concentration on the iron contents of the Fe‐Ni alloy foils were studied. The phase composition and surface morphology with various iron contents were characterized by X‐ray diffraction (XRD) and atomic force microscopy (AFM), respectively. Cathodic polarization curves were used to evaluate the role of sodium propargyl sulfonate (PS).

Nanocrystalline Fe‐Ni alloy foil containing up to 64 wt. percent iron can be obtained from a chloride‐sulfate based solution. The foil converts from a face‐centered cubic (fcc) Fe3Ni2 phase to a mixture of fcc and body‐centered cubic (bcc) Fe7Ni3 with increase in iron content from 55.0 wt. percent to 63.5 wt. percent. AFM studies revealed that the foil had a fine grain structure with a roughness of 30 nm and grain size of 30 nm. With iron increasing to 63.5 wt. percent some islands appeared on the surface. This structure was related to the development of a (200) fiber texture in the BCC phase. Sodium propargyl sulfonate accelerates the discharge of nickel and inhibits the discharge of Fe.

The foil has many industrial applications in the area of memory devices for computers, laser components and precise instruments.

The paper presents a process to produce a foil with iron up to 64 wt. percent from a chloride‐sulfate based solution used in normal DC mode. The dependence of microstructure and surface morphology on iron contents also is presented. Until now, there has been little research or reports on this subject.

The purpose of this work is to present the strategies and current state of development in the field of micro solid oxide fuel cells (μSOFC).

In the paper recent strategies of conventional and single chamber μSOFC are described. Some examples based on the author's research are presented.

It can be concluded that scale down of ceramic technologies is still more popular than MEMS. However, MEMS‐based technologies become recently to be used more frequently.

The work is limited to the description of materials and technologies used in μSOFC.

The review presents very recent research in μSOFC. The results demonstrate critical areas in development of suitable technologies.

The paper presents an application of the scaling theory in a description of energy losses in soft magnetic materials in order to improve an agreement between measurements and theoretical models.

The scaling theory allows the description of energy losses by a generalized homogenous function, which depends on scaling exponents α, β and amplitudes Γ⁽ⁿ⁾. The values of the scaling exponents and amplitudes were estimated on the basis of measurement data of total energy losses.

The main findings of the paper are: the linear relationships between the scaling exponents α and β, the data collapse of energy losses and the scaling laws for asymptotic exponents of energy losses derivatives.

The origin of the data collapse and the relationship between the scaling exponents will be the subject of further research with the aid of renormalization group method

The paper could be useful both for device designers and researchers involve in computational electromagnetism. Particularly, the data collapse allows a comparison of energy loss values measured in laboratories on different samples and by different methods.

The application of the scaling theory in a description of energy losses in soft magnetic materials improves an agreement between measurement and theoretical models.

This study aims to review the recent advancements in high entropy alloys (HEAs) called high entropy materials, including high entropy superalloys which are current potential alternatives to nickel superalloys for gas turbine applications. Understandings of the laser surface modification techniques of the HEA are discussed whilst future recommendations and remedies to manufacturing challenges via laser are outlined.

Materials used for high-pressure gas turbine engine applications must be able to withstand severe environmentally induced degradation, mechanical, thermal loads and general extreme conditions caused by hot corrosive gases, high-temperature oxidation and stress. Over the years, Nickel-based superalloys with elevated temperature rupture and creep resistance, excellent lifetime expectancy and solution strengthening L12 and γ´ precipitate used for turbine engine applications. However, the superalloy’s density, low creep strength, poor thermal conductivity, difficulty in machining and low fatigue resistance demands the innovation of new advanced materials.

HEAs is one of the most frequently investigated advanced materials, attributed to their configurational complexity and properties reported to exceed conventional materials. Thus, owing to their characteristic feature of the high entropy effect, several other materials have emerged to become potential solutions for several functional and structural applications in the aerospace industry. In a previous study, research contributions show that defects are associated with conventional manufacturing processes of HEAs; therefore, this study investigates new advances in the laser-based manufacturing and surface modification techniques of HEA.

The AlxCoCrCuFeNi HEA system, particularly the Al0.5CoCrCuFeNi HEA has been extensively studied, attributed to its mechanical and physical properties exceeding that of pure metals for aerospace turbine engine applications and the advances in the fabrication and surface modification processes of the alloy was outlined to show the latest developments focusing only on laser-based manufacturing processing due to its many advantages.

It is evident that high entropy materials are a potential innovative alternative to conventional superalloys for turbine engine applications via laser additive manufacturing.

The sustainable performance of hotels which constitute a major part of the tourism industry, gains increasing importance day by day. Sustainability has become mandatory not only for the tourism industry but also for all industries producing goods and services. Reducing the negative impact of development on the environment and environmental innovation which aims to benefit from natural resources and energy effectively and consciously helps hotels to be sustainable. The tourism industry has a complex structure and exists as being intertwined with other branches of science. Tourism, which is a multidisciplinary industry, is nourished by other branches of science as well as supplies other fields of science by providing working space. Some new solutions that are put forward by materials science and engineering take place in the tourism industry as new innovations. Owing to this interaction, the workload of the personnel working in hotels is reduced and the enterprises save material and energy. At the same time, the customers who benefit from the services of the hotels consume the services in more comfortable and safer environments.

Ceramic materials are generally used in toilet and bathroom parts of hotels. However, ceramics are observed to be used in lobbies, cafes, restaurants, pools, facades, and similar areas in addition to toilets and baths in hotels. The aim of this study is to identify new ceramic solutions that affect and contribute to the sustainability of the hotels which is a major sector under the roof of the tourism industry and to contribute the literature. In order to actualize this aim, the document analysis method which is one of qualitative research methods was used and the literature search was carried out to identify new ceramic solutions. The result of study includes moisture control tiles with the ability to keep the humidity at normal standards in terms of human health and that can be used in hotels, facade systems that clean themselves and the polluted air, thermal coating systems for heat insulation, antibacterial materials that provide hygiene, and dirt repelling products. Also, it is seen that there are new ceramic solutions such as costless night lighting and security strips as well as materials with a phosphorescence property for aesthetical purposes and also, tiles with heat control which offer different possibilities aesthetically. It is observed that the different benefits obtained from each of identified new ceramic solutions ease off the workload of personnel working in the hotels, enable material and energy saving in hotels and at the same time, provide an accommodation in a more comfortable and safer environment for customers. In addition to this, the use of high-technology ceramics and nanomaterials in the field of tourism creates places where technology and aesthetics combine.

The purpose of this paper is to study the cavitation erosion stages of AA5083 by electrochemical noise (EN).

EN technology including noise resistance and fast Fourier transform were used to characterize the electrochemical process during the cavitation erosion process.

AA5083 suffers from uniform corrosion during the cavitation erosion process. The whole cavitation erosion process can be divided into three stages: incubation stage, acceleration stage and steady-state stage. EN signals showed obvious differences in different stages of cavitation erosion.

EN technique is a suitable method that can be used to study cavitation erosion mechanism and identify cavitation erosion stages.