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The effect of the substitution of Y3+ by Nd3+ on the structural and magnetic properties of neodymium-doped yttrium iron garnet, NdxY3−xFe5O12 with x in the range of 0–2.5, is presented. Oxide powders of Fe2O3, Nd2O3, and Y2O3 were mixed in a stoichiometric ratio and milled for 5 h using high-energy ball milling, before being uniaxially pressed at 900 MPa and annealed at 1373 K for 2 h to obtain NdxY3−xFe5O12 (0 ≤ x ≤ 2.5). It was found that the mechanical milling of oxides followed by annealing promotes the complete structural formation of the garnet structure. Additionally, the X-ray diffraction patterns confirm the complete introduction of Nd3+ into the garnet structure with a neodymium doping concentration (x) of 0–2.0, which causes a consistent increment in the lattice parameters with the Nd3+ content. When x is higher than 2.0, the yttrium orthoferrite is the predominant phase. Besides, the magnetic results reveal an increase in the Curie temperature (583 K) as the amount of Nd3+ increases, while there was enhanced saturation magnetization as well as modified remanence and coercivity with respect to non-doped YIG.

In this research, aerodynamic tests were carried out at different speeds by using Solidworks Flow Simulation software in the Tesla Cybertruck vehicle, knowing the results of the drag and lift coefficients. The method was selected in three dimensions, the continuity equations and the Navier-Stokes equations that were solved by the finite volume method, the k-ɛ model was chosen to close the amounts of turbulence.

El granate de hierro itrio, YIG (Y3Fe5O12), es un cerámico con propiedades magnéticas, dieléctricas y ópticas, las cuales se atribuyen a su estructura cristalina. El YIG contiene 160 iones que forman huecos tetraédricos, octaédricos y dodecaédricos; así como a la ubicación de los cationes, distorsión e interacciones atómicas. Su baja coercitividad y mínimas pérdidas por corriente inducida es útil en dispositivos que operan en microondas. Con la finalidad de ampliar el rango de aplicaciones se sustituyen iones de Y3+ (1.019Å y 0 µB) por Ce3+ (1.01Å y 1.0 µB), Nd3+ (1.109Å y 3.62 µB) y Bi3+ (1.17Å y 0 µB). Se evalúa el efecto del tipo y nivel de dopaje, sobre la estructura cristalina y propiedades magnéticas del YIG dopado, cuando se emplea molienda de alta energía asistida con tratamiento térmico como método de síntesis

In this work, the effect of the boronizing thermochemical treatment on the adherence and surface morphology of the boride layer formed in DIN UC1 steel was evaluated. The process was carried out by packing at the temperature of 1273 K, at the times of 4800, 6000, 7200 and 14400 seconds. The HRC adherence test based on the VDI 1398 standard, was simulated in COMSOL 5.0®; analysing the effect of the thickness of the boride layer and the roughness on the Von Mises stress, in addition to the stress on the indentation footprint; in which it was observed that by increasing the thickness of the layer from 22.2 to 37.8 µm the stresses increased, and therefore the adhesion of the layer on the substrate improved, which causes only the formation of microcracks. On the other hand, in the greater layer thickness (60.04 µm) the layer delaminates. Therefore, for an industrial application of DIN UC1 steel treated thermochemically by borurization, layer thicknesses up to 37.8 µm are recommended.