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Ferromagnetic materials may be affected by the presence of local losses due to defects or magnetic anomalies caused by machining processes. To highlight such anomalies is not easy; a noninvasive thermographic method has been refined to allow a proper comparison of different machining processes’ impact on the iron losses. Specimens obtained with punching, wire erosion, and laser cut have been analyzed using a high-speed IR camera when subjected to alternate magnetization at different frequencies. Also, the same technique has been adopted to the assembled stacks to investigate more simultaneous phenomena. The possibility to point out localized anomalies should be exploited to foresee and avoid electrical machines core faults. [ABSTRACT FROM AUTHOR]

This study provides information on the hybrid steel sheets available for the use of carmakers. The automotive industry has been working on many different areas simultaneously to improve the performance of vehicles such as light-weighting, safety, clean energy resources, and noise-vibration-harshness (NVH). Steel is the dominant material for most vehicles. However, there are currently many alternative materials to steel such as aluminum, magnesium, titanium, plastics, carbon fiber, etc. Therefore, a lot of research has been done to keep steel as the material of choice for vehicles by the steel and material industries. Hybrid steel materials have been introduced to compete with these alternative materials. Hybrid steel materials are developed for light-weighting and/or acoustic insulation applications. They provide a good balance between cost and weight. In this study, the definition of hybrid steel materials is explained. Emerging and available products with their technical properties and possible applications are reviewed. [ABSTRACT FROM AUTHOR]

BACKGROUND Aroma scalping is a very common problem and can affect the sensory quality of packaged food. To study the aroma scalping characteristics of polyethylene terephthalate laminated steel (PET‐LS), the sorption kinetics of six common aroma compounds (2‐pentanone, 2‐heptanone, hexanal, citral, butyl acetate, isopentyl acetate) in foods were assessed for drawn–redrawn cans made with PET‐LS. RESULTS: Storage temperature and initial concentration were proved as important factors to affect compound sorption and diffusion for flavors. The correlation between logarithm of equilibrium absorption ln M∞ and reciprocal of absolute temperature 1/T showed good linear relationship (R2 = 0.9380–0.9998) at 4 °C, 20 °C and 50 °C, and the M∞ obtained by the experiment was very close to the predicted value at 37 °C. At low initial concentration (below 500 µL L−1), the absorption capacity and initial concentration showed a slow linear growth trend, whereas there was a rapid change at high initial concentration. The values of diffusion coefficient D were on the order of 10−11–10−12 m2 day−1, which were lower than reported for other polymer materials (linear low‐density polyethylene, polybutylene succinate, polylactic acid). CONCLUSION: The equilibrium absorption amount of each flavor component was dependent on the temperature under the same concentration (500 µL L−1). The Fickian diffusion model was used for fitting the experimental kinetics values satisfactorily (R2 = 0.9158–0.9885). © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this paper, the effects of using laminated steel and solid steel for the magnetizing fixture components on the magnetization energy needed for saturation, magnetization profile, and motor performance are presented. Three combinations of fixture core and back iron materials have been analyzed using 2-D finite element analysis as well as experiments. The potential issues with the use of solid steel as fixture components have been explained. The results indicate that the magnetization fixtures made with solid steel components require higher energy to generate the magnetization field needed for magnet saturation and in most practical cases lead to partially magnetized magnet and poor motor performance. The use of laminated steel for all soft magnetic components in the magnetization fixture is highly recommended. [ABSTRACT FROM AUTHOR]

The strain distribution in a multi-layered steel composed of brittle martensitic steel (WT-780C) and ductile austenitic steel (SUS304) during a compressive test was measured by the electron moiré method. A very fine model grid with 5 μm spacing was fabricated using electron lithography techniques on the surface of the specimen and an electron beam scan in which spaces are almost the same as those of the model grid can be used for the master grid. The difference between the amounts of secondary electrons per primary electron causes moiré fringes that consist of bright and dark parts. The spacing of the electron moiré fringe was measured, and the strain on the specimen was calculated by using the spacing of the electron moiré fringe and the spacing of the electron beam scan. The strain distribution was not uniform for each steel sheet and the boundaries. The strain near the boundary between the different steel sheets is larger than that in the SUS304 sheet and that in the WT-780C sheet. [ABSTRACT FROM PUBLISHER]

The new model is based on a modified Steinmetz equation and employs a hysteresis-loss multiplicative coefficient and a combined coefficient for eddy-current and excess losses, both coefficients being variable with induction and frequency. The material model coefficients are first identified through multifrequency tests with sine-wave excitation. The iron-loss increase due to pulsewidth-modulation supply is estimated using global waveform parameters of the nonsinusoidal voltage. The study includes three different grades of non-grain-oriented electric steel. The data cover a wide range of fundamental frequency from 10 to 600 Hz and induction from 0.05 to 2 T. The errors of the computational model are small at relatively low fundamental frequency and increase thereafter. The main advantages of the model are its simplicity of use and minimal data requirements. [ABSTRACT FROM AUTHOR]

Abstract: Steel/polymer/steel laminate sheets, commonly known as laminated steels, received attention for their superior noise damping properties in automotive applications. Published work indicates that the tensile properties of the laminated steel follow the prediction of the rule of mixtures. The flexural response of the laminated steel, however, depends on the type of the sandwich configuration. The flexural rigidity of the vibration-damping type of laminated steel is lower than the value calculated using beam theory. In industrial scale numerical simulations, automotive body panels are usually represented by using a single layer of shell element. Limited research work on finite element (FE) modeling of laminated steel has indicated that the vibration-damping type of laminated steel is better represented by using two layers of shells. It is logical to relate the simplest FE representation to the way the flexural rigidity of the laminated steel that conforms to the prediction using the beam theory. This paper examines the flexural response of the vibration-damping type of laminated steel through the comparison of beam theory predictions with the experimental results for cantilever beam and three-point bending configurations. It was found that the analytical solution for the split beam is in good agreement with the experimental results. This finding confirms the FE model that represents the vibration-damping type of laminated steel using two layers of shell with tied interface. The simulations using this method yielded good correlations with the experimental results for the two flexural loading cases studied in this paper. [Copyright &y& Elsevier]

Abstract: Laminated steel is a sheet metal product consisting of two steel sheets with a thin, viscoelastic polymeric layer between them. The product integrates structural function with sound and vibration absorbing capabilities. Under bending operations, such as wiping or V-press bending, however, the walls of bent parts develop an undesirable curl and consequently an apparently larger spring-back angle. This work addresses bending of laminated steel strips by wiping and their resulting shape using both experimental and numerical approaches. The experimental results indicate that for the materials and geometry used here, the curl can be reduced somewhat by employing larger punch strokes. In addition, the curl decreases slowly with time over many days due to the viscoelasticity of the polymer layer. The reduction in curl due to both effects, however, is not sufficient to eliminate the problem. A numerical, finite-element model to simulate the experiments was developed and yielded reasonably good agreement with the experiments. A parametric study indicated that the curl decreases with decreasing yield stress and increasing thickness of the steel sheets. Increasing the shear stiffness of the polymer layer from zero leads to increasing curl until a maximum is reached. Further increase yields a slow decrease in the curl. [Copyright &y& Elsevier]

Abstract: Tin free steel plate (TFS) that is substrate of the PET-laminated steel has been treated by atmospheric pressure plasma at room temperature in order to enhance the surface adhesive properties. After plasma treatment, the water-contact angle measurement was conducted and the surface-free energy of the TFS plate was proved to be increased. Besides, the peel-off test for adhesive property of PET-laminated steel also was conducted and the adhesion between TFS and polymer (PET) was enhanced remarkably. From the results of XPS and SEM analysis, we could confirm that new functional groups causing the adhesion enhancement were generated under the carbon cleaning effect and surface oxidation effect by reactive species in the plasma, such as atomic oxygen etc. [Copyright &y& Elsevier]

A model of core losses, in which the hysteresis coefficients are variable with the frequency and induction (flux density) and the eddy-current and excess loss coefficients are variable only with the induction, is proposed. A procedure for identifying the model coefficients from multifrequency Epstein tests is described, and examples are provided for three typical grades of non-grain-oriented laminated steel suitable for electric motor manufacturing. Over a wide range of frequencies between 20-400 Hz and inductions from 0.05 to 2 T, the new model yielded much lower errors for the specific core losses than conventional models. The applicability of the model for electric machine analysis is also discussed, and examples from an interior permanent-magnet and an induction motor are included. [ABSTRACT FROM AUTHOR]