4results about How to "Magnetically stable" patented technology

The invention relates to the technical field of permanent magnet preparation, and particularly discloses a high-temperature-resistant neodymium-iron-boron magnet and a preparation method thereof. The high-temperature-resistant neodymium-iron-boron magnet comprises the following elements in percentage by mass: 17.4%-19.5% of Nd, 0.66%-0.72% of B, 38.37%-41.19% of Fe, 0.36%-4.8% of Dy, 0.18%-0.3% of Nb, 0.18%-0.3% of Al, 0.03%-0.09% of Cu, 29.1%-34.8% of an alloy rapid hardening sheet and the balance of unremovable impurities, wherein the alloy rapid hardening sheet contains Pr, Tb, Bi and Sn; the preparation method comprises the following steps: grinding the surface of an alloy rapid hardening sheet to be bright, mixing the alloy rapid hardening sheet with a pretreated magnet block, adding zirconium oxide balls, putting into a reaction kettle of a rotary diffusion furnace, vacuumizing the reaction kettle, introducing argon, rotating at the rotating speed of 4-6r / min, keeping the temperature at 700-704 DEG C for 3-7h, and carrying out rotary diffusion, so as to obtain the zirconium oxide-based composite material. And then carrying out heat preservation at 850-950 DEG C for 2-4 hours for high-temperature diffusion and heat preservation at 450-550 DEG C for 2-4 hours for tempering heat treatment by using a vacuum tube furnace in a vacuum environment. The high-temperature-resistant neodymium-iron-boron magnet has the advantage that the defect that heat resistance of a conventional neodymium-iron-boron magnet is still insufficient is overcome.

The invention provides a gradient magnetizing method of a Halbach magnet ring, which comprises a magnet ring, the cross section of the magnet ring is sequentially provided with magnetic poles from outside to bottom, from left to top, from top to bottom, from top to bottom, from top to bottom, from top to bottom, from top to bottom, from top to bottom and from top to bottom, and from top to bottom, and the magnet ring is axially and asymmetrically magnetically distributed and comprises a low-magnetic-force upper magnetic area and a high-magnetic-force lower magnetic area; the magnetizing process comprises the following steps: a horizontal magnetic pole magnetizing step: applying a horizontal magnetizing magnetic field to a left magnetic pole area and a right magnetic pole area, and forming gradient magnetization with weak upper part and strong lower part by regulating the magnetic field intensity of the upper part to be lower than the magnetic field intensity of the lower part; and axial magnetic pole magnetizing: applying an axial magnetizing magnetic field to the downward and upward magnetic pole areas, and forming gradient magnetization with weak upper part and strong lower part by regulating the magnetic field intensity of the upper part to be lower than the magnetic field intensity of the lower part. The problems that in the prior art, the magnetizing requirement cannot be met, and magnetic disorder is likely to be generated are solved.

The utility model discloses an anti-toppling ice tray of an ice maker, which comprises a base plate, a plurality of ice block accommodating strips are inserted into the upper surface of the base plate, the front surfaces of the ice block accommodating strips are fixedly connected with front positioning pin plates, and the rear surfaces of the ice block accommodating strips are fixedly connected with rear positioning pin plates. Locating pins are arranged on the lower surface of the front locating pin plate and the lower surface of the rear locating pin plate, front locating holes are formed in the upper surface of the base plate, rear locating holes are formed in the upper surface of the base plate, a first magnet is fixedly connected to the lower surface of the ice block containing strip, and a second magnet is fixedly connected to the lower bottom wall of the base plate. By means of the device, deformation or falling in advance can be avoided, so that the anti-toppling effect is achieved, and it is guaranteed that the ice blocks are regular in shape.

The application relates to the field of magnetic core materials, and particularly discloses a low-temperature sintering NiZn magnetic core material and a preparation method thereof. The low-temperature sintering NiZn magnetic core material comprises the following raw materials in percentage by mass: NiO 10-20%, ZnO 20-35%, Fe2O3 45-55%, and a sintering aid 2-5%, wherein the sintering aid comprises at least two of Bi2O3, V2O5 and MnO. By optimizing the component proportion of each raw material and the sintering aid, the application realizes low-temperature sintering below 950 DEG C, can reduce energy consumption by more than 30% compared with the traditional process which needs to be sintered above 1200 DEG C, and solves the problems of easy decline of magnetic performance, insufficient sintering density and increased loss caused by low-temperature sintering, so that the prepared magnetic core material has low loss, a density greater than or equal to 94%, and a magnetic permeability greater than or equal to 85 (1MHz), meets the demand of high-frequency electronic devices, and has high compatibility with low-temperature packaging materials.