Abstract: An alloy cast strip preparation method includes a melting process and a casting cooling process. The melting process includes controlling a power of an induction melting furnace to perform a cyclic heat treatment to completely melt an alloy raw material before a surface temperature of a melt obtained by melting the alloy raw material is raised to 1300° C., and, after the alloy raw material is melted, adjusting the power of the induction melting furnace to stabilize the surface temperature of the melt at a temperature in a range from 1400° C. to 1500° C. The casting cooling process includes performing casting cooling on the melt arranged on a surface of a rotary cooling roll to obtain an alloy cast strip while controlling a surface linear velocity of the rotary cooling roll to be from 1.5 m/s to 2.25 m/s.

Abstract: Disclosed herein is a method for manufacturing an R-T-B permanent magnet and the magnet made with the method. The method may include preparation of strip pieces by melting and casting, preparing coarse powder by hydrogen decrepitation of the strip pieces; milling the powder into fine powder; pressing the fine powder is pressed to form a compact, pre-sintering the compact in vacuum or inert gas, machining the pre-sintered block to a desired shape; and dispersing the heavy rare earth compound powder into an organic solvent to prepare a slurry and a second sintering step.

Abstract: An alloy cast strip includes grains having R2Fe14B-type compound as main phase, where R denotes a rare earth element, Fe denotes iron, and B denotes boron. The grains include non-columnar grains having an aspect ratio in a range from 0.3 to 2 and columnar grains having an aspect ratio equal to or larger than 3. A ratio of an area of the non-columnar grains to a total area of the grains is equal to or larger than 60% and a ratio of a number of the non-columnar grains to a total number of the grains is equal to or larger than 75%. A ratio of an area of the columnar grains to the total area of the grains is equal to or smaller than 15% and a ratio of a number of the columnar grains to the total number of the grains is equal to or smaller than 10%.

Abstract: A sintered neodymium-iron-boron magnet, the main components thereof comprising rare-earth elements R, additional elements T, iron Fe and boron B, and having a rare-earth-enriched phase and a main phase of a Nd2Fe14B crystal structure. The sum of the numerical values of the maximum magnetic energy product (BH)max in units of MGOe and the intrinsic coercive force Hcj in units of kOe is not less than 70. The manufacturing method of the sintered neodymium-iron-boron magnet comprises alloy smelting, powder making, powder mixing, press forming, sintering and heat treatment procedures. By controlling the component formulation and optimizing the process conditions, the sintered neodymium-iron-boron magnet is enabled to simultaneously have a high maximum magnetic energy product and a high intrinsic coercive force.

Abstract: The present invention discloses a rare earth permanent magnet and a method for preparing same. The material of the rare earth permanent magnet has a heavy rare earth element volume diffusion phenomenon at a depth of 5 ?m to 100 ?m from the surface of the magnet to the interior of the magnet along the magnetic field orientation direction, thereby forming a volume diffusion layer region; the volume diffusion layer region is divided into magnet units having a volume of 10*100*5 ?m, and the concentration difference of the heavy rare earth elements of the magnet units at different positions in the volume diffusion layer is below 0.5 at %. The present invention provides a sintered NdFeB magnet of high intrinsic coercive force Hcj on the premise of not influencing the remanence Br and the maximum magnetic energy product (BH)max of products.

Abstract: The present invention discloses a rare earth permanent magnet and a method for preparing same. The material of the rare earth permanent magnet has a heavy rare earth element volume diffusion phenomenon at a depth of 5 ?m to 100 ?m from the surface of the magnet to the interior of the magnet along the magnetic field orientation direction, thereby forming a volume diffusion layer region; the volume diffusion layer region is divided into magnet units having a volume of 10*100*5 ?m, and the concentration difference of the heavy rare earth elements of the magnet units at different positions in the volume diffusion layer is below 0.5 at %. The present invention provides a sintered NdFeB magnet of high intrinsic coercive force Hcj on the premise of not influencing the remanence Br and the maximum magnetic energy product (BH)max of products.

Abstract: The present invention discloses a rare earth permanent magnet and a method for preparing same. The material of the rare earth permanent magnet has a heavy rare earth element volume diffusion phenomenon at a depth of 5?m to 100 ?m from the surface of the magnet to the interior of the magnet along the magnetic field orientation direction, thereby forming a volume diffusion layer region; the volume diffusion layer region is divided into magnet units having a volume of 10*100*5 ?m, and the concentration difference of the heavy rare earth elements of the magnet units at different positions in the volume diffusion layer is below 0.5 at %. The present invention provides a sintered NdFeB magnet of high intrinsic coercive force Hcj on the premise of not influencing the remanence Br and the maximum magnetic energy product (BH)max of products.

Abstract: The present invention discloses a rare earth permanent magnet and a method for preparing same. The material of the rare earth permanent magnet has a heavy rare earth element volume diffusion phenomenon at a depth of 5 ?m to 100 ?m from the surface of the magnet to the interior of the magnet along the magnetic field orientation direction, thereby forming a volume diffusion layer region; the volume diffusion layer region is divided into magnet units having a volume of 10*100*5 ?m, and the concentration difference of the heavy rare earth elements of the magnet units at different positions in the volume diffusion layer is below 0.5 at %. The present invention provides a sintered NdFeB magnet of high intrinsic coercive force Hcj on the premise of not influencing the remanence Br and the maximum magnetic energy product (BH)max of products.

Abstract: Disclosed herein is a method for manufacturing an R-T-B permanent magnet and the magnet made with the method. The method may include preparation of strip pieces by melting and casting, preparing coarse powder by hydrogen decrepitation of the strip pieces; milling the powder into fine powder; pressing the fine powder is pressed to form a compact, pre-sintering the compact in vacuum or inert gas, machining the pre-sintered block to a desired shape; and dispersing the heavy rare earth compound powder into an organic solvent to prepare a slurry and a second sintering step.

Abstract: A sintered neodymium-iron-boron magnet, the main components thereof comprising rare-earth elements R, additional elements T, iron Fe and boron B, and having a rare-earth-enriched phase and a main phase of a Nd2Fe14B crystal structure. The sum of the numerical values of the maximum magnetic energy product (BH)max in units of MGOe and the intrinsic coercive force Hcj in units of kOe is not less than 70. The manufacturing method of the sintered neodymium-iron-boron magnet comprises alloy smelting, powder making, powder mixing, press forming, sintering and heat treatment procedures. By controlling the component formulation and optimizing the process conditions, the sintered neodymium-iron-boron magnet is enabled to simultaneously have a high maximum magnetic energy product and a high intrinsic coercive force.