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This article analyses the effects of deformation on the structure of CMnSi steel at various deformation levels. After hot forging, the structure of CMnSi steel comprises coarse-sized alpha and pearlite particles. The average grain size of steel after forging was 100 μm. After hot rolling, the grain size gradually decreases, with the average size of the ferrite and pearlite grains measured as 60 μm. After that, CMnSi steel was subjected to cold deformation at levels of 40%, 60%, and 80%. The grain size of the CMnSi steel sample after 80% cold deformation reached level 7, corresponding to about 25 μm. For a deformation level of 40%, the grain size was level 5, corresponding to 40 μm, while a deformation level of 60% produced a grain size of 35 μm, corresponding to level 6. In addition, scanning electron microscopy showed that after 80% deformation, smaller particles with a size of about 5 μm appear inside the parent particles. Moreover, energy-dispersive X-ray spectroscopy analysis revealed the carbide appearance in the form M23C6, with M being a mixture of Fe and Mn. These carbides have a fine size of about 1–2 μm and contribute to the prevention of particle growth during subsequent heat treatments.

This article proposes a structure and decentralized control method for a multilevel five-phase inverter connected to five-phase permanent magnet synchronous motor (5PMSM). The power converter used connects full bridge cascade cells in series with a fixed voltage of direct current source. Information about the position and total active cells in phase and column will be exchanged by cells, which serves as data for cells to determine their own vector and switching time. Decentralized inverter control will improve reliability in 5PMSM operation. By adding or removing cells in series in each-phase, it is possible to adjust the modulation voltage to correspond to the motor’s operation. In the event of an open circuit problem in any one or two-phases of the motor, the inverter will automatically adjust its structure and operating parameters to ensure the lowest electromagnetic moment fluctuations; this also applies when some phases of the inverter are faulty. A decentralized control power converter allows the motor to operate continuously, without interruption, when an open circuit occurs. The decentralized structure and space vector pulse width modulation method focus on analyzing 5PMSM control in the direct and quadrature (d-q) coordinate system, in evaluation and verification based on the Matlab/Simulink simulation model.

A new solvothermal approach has been developed for the synthesis of monodisperse and well-crystallized SmVO4nanocrystals with different morphologies from the reaction of Sm(OA)3and VO4(TOA)3complexes in toluene in the presence of surfactant (oleylamine or oleic acid) through a solvothermal pathway. The present solvothermal approach is simple and reproducible and employs a relatively mild reaction temperature. The obtained SmVO4nanocrystals were characterized by means of transmission electron microscopy, selected area electronic diffraction (SAED), X-ray diffraction (XRD), Elemental dispersive spectrum, X-ray photoelectron spectra (XPS), UV−visible, thermogravimetric differential thermal analysis TGA−DTA, FTIR, and N2adsorption/desorption isotherms (BET) techniques. The SAED and XRD patterns confirmed that the structure of the synthized SmVO4nanocrystals is single-crystalline tetragonal. The size, shape, and aspect ratio of products can be readily controlled by adjusting the reaction parameters, such as the nature and amount of surfactant, and the concentration of the metal complex precursors. The SmVO4nanocrystals with spherical and hexagonal shapes were obtained by using oleylamine or oleic acid as a nonselective and selective surfactant, respectively, under the same synthesis conditions. Furthermore, the average particle size is tunable from 30 to 3 nm by increasing the oleylamine concentration from 0.025 to 0.43 M in the synthesis solution. The shape evolution from nanocores to nanowires can also be obtained by increasing the metal complex precursor concentration; it is associated with the increase in the chemical potential in the reaction solution. The XPS results revealed only one oxidation state for Sm3+and V5+on the SmVO4nanocrystal surface, even after calcinations compared two oxidation states (e.g., Sm2+/Sm3+and V4+/V5+) of the single samarium oxide and vanadium oxide NPs, respectively. Our synthetic approach can be further extended to the synthesis of other uniform rare earth orthovanadate, molybdate, and tungstate nanocrystals.