7 results about "Magnetic exchange" patented technology

The invention discloses an R-T-B rare earth permanent magnet and a preparation method and application thereof, and belongs to the technical field of permanent magnet materials. The preparation method comprises the following steps that an alloy film R1xFeyGazVw for grain boundary diffusion is attached to the surface of an R-T-B basic magnet, and then the R-T-B rare earth permanent magnet is obtained through high-temperature diffusion and tempering heat treatment, in the alloy film R1xFeyGazVw for grain boundary diffusion, x, y, z and w are the mass percentages of corresponding elements, the total amount is 100%, 51 < = x < = 55.7, 40 < = y < = 44.2, 4.3 < = z < = 9, 0 < = w < = 4.7, R1 is at least one or more of Pr and Nd, and V is at least one or more of Al and Cu. The components of the alloy film are accurately controlled, so that the alloy film can stably form a nonmagnetic phase of 6: 13: 1 composed of rare earth, iron and gallium at the grain boundary of a basic magnet in subsequent heat treatment, the magnetic exchange coupling effect among main phase grains is effectively isolated, and the coercive force is remarkably improved. And the preparation method of the R-T-B rare earth permanent magnet provided by the invention does not depend on heavy rare earth elements.

This application relates to the field of microscopy technology, and more particularly to a magnetic high-rigidity leveling adapter for microscopes. The technical solution includes a base fixed to a microscope support column, a support stage, and an adjustment connector. The support stage is equipped with a magnet for rapid sample adsorption. The adjustment connector includes a fixed ball, three bolts with ball heads, and a tension spring connecting the base and the support stage. The bottom surface of the support stage has two vertically aligned V-grooves and a planar contact portion. Each bolt has a hydraulic locking mechanism that controls the horizontal movement freedom of the ball head through a pressing head. During adjustment, pressing the corresponding bolt fixes the ball head at that point horizontally, while allowing the other two ball heads to slide freely, preventing jamming. After adjustment, all horizontal movement of the ball heads is locked. This invention enables non-destructive upgrading of old microscopes, quick sample magnetic exchange, eliminates adjustment drift and jamming problems, and significantly improves imaging stability and operational efficiency.

The invention belongs to the field of two-dimensional materials, and particularly relates to a magnetic regulation and control technology of transition metal sulfide molybdenum disulfide (MoS2), transition metal manganese (Mn) is taken as an example, the influence of Mn doping on the magnetic performance of a MoS2 film is systematically researched, and the magnetic performance of the MoS2 film can be regulated and enhanced. The quantitative relation between the Mn doping concentration x and the magnetic performance of the Mo1-xMnxS2 film is established through experiments for the first time, it is successfully shown that the magnetic performance of the MoS2 film can be effectively enhanced through Mn doping, the saturation magnetization is 0.0096 emu / mm < 3 > when the saturation magnetization is x-9.7% and is about 3 times that of a sample doped with a small amount of Mn, and the coercive force is about 160 Oe; the magnetic enhanced dual mechanisms of the MoS2 film, namely the local magnetic moment introduced by Mn atoms and enhanced magnetic exchange interaction, are illuminated for the first time. Research on the magnetic performance of the Mo1-xMnxS2 film regulated and controlled by doping of Mn provides reference for expanding the application of the two-dimensional material in spintronics and magnetic storage devices.

Magnetic exchange system for generating synchronized magnetic movement, comprising: a support structure with two concentrically arranged hollow cylinders (cylinder 1 and cylinder 2) made of magnetically insulating material, which rotate around a common axis, wherein both cylinders have radial openings (holes) that are offset from each other in such a way that an opening in cylinder 1 is always covered by a closed wall surface of cylinder 2 and vice versa, at least one track arranged between the cylinders with at least one movable magnet (magnet 1), a magnet (magnet 2) arranged stationary inside cylinder 1 and a magnet (magnet 3) arranged stationary outside cylinder 2; characterized in that the magnetic interaction between magnet 1 and optionally magnet 2 or magnet 3 is controlled via the openings by the rotation of the cylinders in such a way that magnet 1 performs an oscillating movement between the cylinders.

This invention discloses a high-boron Y–Ce–Co co-substituted nanocrystalline material and its preparation method. The general chemical formula of the nanocrystalline material, expressed as a percentage by mass, is: [RE x (Y y Ce 1‑y ) 1‑x ] z Fe 100‑z‑u‑v‑w Co u M v B w The composition is defined as follows: 0 ≤ x ≤ 0.9, 0.05 ≤ y ≤ 0.9, 25 ≤ z ≤ 35, 5 ≤ u ≤ 50, 0 ≤ v ≤ 3, 1.7 ≤ w ≤ 3. This invention utilizes Y–Ce–Co co-substitution to synergistically regulate the lattice occupancy, elemental valence states, and magnetic exchange interactions of the main phase, significantly improving the temperature stability of the Ce-rich system. Addressing the issues of abnormal grain growth and excessive Laves phase precipitation caused by Co introduction, increasing the mass percentage of B significantly enhances the alloy's amorphous forming ability, refines the main phase grains, and suppresses the formation of harmful second phases. Based on this compositional design, a low-linear-velocity melt rapid quenching process (12 to 18 m / s) can directly prepare materials with uniform nanocrystalline structures without subsequent crystallization annealing, achieving high coercivity and high temperature resistance while significantly reducing raw material costs.

This invention discloses a silver-coated magnetic metal filler with magnetic field shielding effectiveness, its preparation method, and its application, relating to the field of electromagnetic shielding materials technology. The method includes: acid washing of magnetic metal powder to obtain acidified magnetic metal powder; adding the acidified magnetic metal powder to a silver nitrate solution, adding grease, and stirring to obtain activated magnetic metal powder; uniformly mixing the activated magnetic metal powder, reducing solution, and silver ammonia solution, adding grease again, and stirring to obtain the silver-coated magnetic metal filler with magnetic field shielding effectiveness. This invention utilizes lightweight, inert grease to avoid oxidation during the magnetic metal displacement activation or chemical silver plating process, significantly enhancing the electromagnetic exchange between the magnetic core and the conductive shell, further improving its shielding effectiveness.

The application belongs to the technical field of magnetic functional materials, and discloses a dense gadolinium-based fluorocarbonate magnetic refrigeration material and a preparation method and application thereof. The chemical formula of the gadolinium-based fluorocarbonate magnetic refrigeration material is NaGdCO3F2. The material is constructed by anti-magnetic sodium ions and fluorine ions and carbonic acid root mixed bridging ligands to form a dense gadolinium-based three-dimensional honeycomb framework structure. The specific spatial arrangement effectively suppresses the magnetic exchange interaction while maintaining high magnetic density, induces short-range magnetic correlation near 0.5K, suppresses the magnetic order temperature to 0.22K, and widens the effective refrigeration temperature range by generating a Schottky abnormal specific heat wide peak. Under 1T, 2T and 7T magnetic fields, the maximum magnetic entropy change reaches 23.1, 38.9 and 59.1 J·kg ‑1 ·K ‑1 respectively. As an excellent low-temperature magnetic refrigerant, the material has the advantages of good thermal stability, simple preparation process and low cost, and has a wide industrial application prospect in the field of adiabatic demagnetization refrigeration materials.