Search Results - "Ohkubo, T"

Structure and chemical compositions of the grain boundary phase in Nd-Fe-B sintered magnets by Sasaki, T.T., Ohkubo, T., Hono, K.

“…We revisited the microstructure of a commercial Nd-Fe-B sintered magnet using scanning electron microscopy (SEM) and aberration corrected scanning transmission…”
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The mechanism of coercivity enhancement by the grain boundary diffusion process of Nd–Fe–B sintered magnets by Sepehri-Amin, H., Ohkubo, T., Hono, K.

“…We discuss the mechanism of the coercivity enhancement by the grain boundary diffusion process (GBDP) using Dy vapor based on detailed microstructural…”
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Grain boundary and interface chemistry of an Nd–Fe–B-based sintered magnet by Sepehri-Amin, H., Ohkubo, T., Shima, T., Hono, K.

“…The compositions of grain boundaries (GBs) and other interfaces surrounding Nd2Fe14B grains in commercial Nd–Fe–B sintered magnets have been investigated by…”
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Micromagnetic simulations on the grain size dependence of coercivity in anisotropic Nd–Fe–B sintered magnets by Sepehri-Amin, H., Ohkubo, T., Gruber, M., Schrefl, T., Hono, K.

“…Micromagnetic simulations of magnetization reversals of Nd–Fe–B anisotropic magnets with exchange-coupled grains demonstrate that the local demagnetization…”
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Magnetic refrigeration material operating at a full temperature range required for hydrogen liquefaction by Tang, Xin, Sepehri-Amin, H., Terada, N., Martin-Cid, A., Kurniawan, I., Kobayashi, S., Kotani, Y., Takeya, H., Lai, J., Matsushita, Y., Ohkubo, T., Miura, Y., Nakamura, T., Hono, K.

“…Magnetic refrigeration (MR) is a key technique for hydrogen liquefaction. Although the MR has ideally higher performance than the conventional gas compression…”
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Formation of non-ferromagnetic grain boundary phase in a Ga-doped Nd-rich Nd–Fe–B sintered magnet by Sasaki, T.T., Ohkubo, T., Takada, Y., Sato, T., Kato, A., Kaneko, Y., Hono, K.

“…We have characterized the microstructures of as-sintered and optimally post-sinter annealed Nd-rich Ga-doped Nd–Fe–B magnets by scanning electron microscopy…”
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Strong and ductile heat-treatable Mg–Sn–Zn–Al wrought alloys by Sasaki, T.T., Elsayed, F.R., Nakata, T., Ohkubo, T., Kamado, S., Hono, K.

“…[Display omitted] A newly developed Mg–Sn–Zn–Al based alloy shows substantial strengthening by artificial aging. A Na-doped Mg–5.4Sn–4.2Zn–2.0Al–0.2Mn–0.1Na…”
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High-coercivity ultrafine-grained anisotropic Nd–Fe–B magnets processed by hot deformation and the Nd–Cu grain boundary diffusion process by Sepehri-Amin, H., Ohkubo, T., Nagashima, S., Yano, M., Shoji, T., Kato, A., Schrefl, T., Hono, K.

“…The grain boundary diffusion process using an Nd70Cu30 eutectic alloy has been applied to hot-deformed anisotropic Nd–Fe–B magnets, resulting in a substantial…”
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Effect of Zn additions on the age-hardening of Mg–2.0Gd–1.2Y–0.2Zr alloys by Honma, T., Ohkubo, T., Kamado, S., Hono, K.

“…We have investigated the microstructures of age hardened Mg–2.0Gd–1.2Y– xZn–0.2Zr ( x = 0, 0.3, and 1.0) (at.%) alloys to understand the remarkable…”
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Effect of post-sinter annealing on the coercivity and microstructure of Nd–Fe–B permanent magnets by Li, W.F., Ohkubo, T., Hono, K.

“…To understand the mechanism of the increase in coercivity caused by post-sinter annealing of Nd–Fe–B-based magnets, we have investigated the microstructures of…”
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Role of Ga on the high coercivity of Nd-rich Ga-doped Nd-Fe-B sintered magnet by Sasaki, T.T., Takada, Y., Okazaki, H., Ohkubo, T., Nakamura, T., Sato, T., Kato, A., Kaneko, Y., Hono, K.

“…We have investigated the effect of Ga on the microstructure and coercivity in Nd-rich Ga-doped Nd-Fe-B sintered magnets with different amount of Ga additions…”
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Solute clustering and grain boundary segregation in extruded dilute Mg–Gd alloys by Hadorn, J.P., Sasaki, T.T., Nakata, T., Ohkubo, T., Kamado, S., Hono, K.

“…Two single-phase Mg–Gd alloys (0.01 and 0.06at.% Gd) were identically hot-deformed through an indirect extrusion process. High-angle annular dark-field…”
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Effect of Nd content on the microstructure and coercivity of hot-deformed Nd–Fe–B permanent magnets by Liu, J., Sepehri-Amin, H., Ohkubo, T., Hioki, K., Hattori, A., Schrefl, T., Hono, K.

“…The microstructure of hot-deformed Nd–Fe–B permanent magnets with different Nd contents was investigated in order to correlate them with the hard magnetic…”
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Microstructure and coercivity of grain boundary diffusion processed Dy-free and Dy-containing Nd Fe B sintered magnets by Kim, T.-H., Sasaki, T.T., Ohkubo, T., Takada, Y., Kato, A., Kaneko, Y., Hono, K.

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Formation mechanism of Tb-rich shell in grain boundary diffusion processed Nd–Fe–B sintered magnets by Kim, Tae-Hoon, Sasaki, T.T., Koyama, T., Fujikawa, Y., Miwa, M., Enokido, Y., Ohkubo, T., Hono, K.

“…We propose a new mechanism for the formation of Tb-rich shell in the Nd–Fe–B sintered magnet that was subjected to the grain boundary diffusion (GBD) process…”
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Faceted shell structure in grain boundary diffusion-processed sintered Nd–Fe–B magnets by Seelam, U.M.R., Ohkubo, T., Abe, T., Hirosawa, S., Hono, K.

“…The grain boundary diffusion process (GBDP) using a heavy rare earth elements (HRE) such as Dy and Tb is known as an effective method to enhance the coercivity…”
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High coercivity Sm2Fe17N3 submicron size powder prepared by polymerized-complex and reduction–diffusion process by Hirayama, Y., Panda, A.K., Ohkubo, T., Hono, K.

“…High coercivity Sm2Fe17N3 submicron size powder was synthesized by the polymerized-complex (PC), hydrogen reduction (HR) and reduction–diffusion (RD)…”
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Large-scale micromagnetic simulation of Nd-Fe-B sintered magnets with Dy-rich shell structures by Oikawa, T., Yokota, H., Ohkubo, T., Hono, K.

“…Large-scale micromagnetic simulations have been performed using the energy minimization method on a model with structural features similar to those of Dy grain…”
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Thermal decomposition of ThMn12-type phase and its optimum stabilizing elements in SmFe12-based alloys by Dirba, I., Harashima, Y., Sepehri-Amin, H., Ohkubo, T., Miyake, T., Hirosawa, S., Hono, K.

“…We investigated the phase stability of SmFe12-based compounds by experimental and computational first-principles approaches. The effect of particle size and…”
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Substantial coercivity enhancement in Dy-free Nd-Fe-B sintered magnet by Dy grain boundary diffusion by Wang, Z., Sasaki, T.T., Une, Y., Ohkubo, T., Hono, K.

“…To date, the highest coercivity reported for Dy-free Nd–Fe–B sintered magnets under the Dy grain boundary diffusion (GBD) process is ∼2.4 T. Therefore,…”
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