| Along with process improvement and technological progress, rare earth permanent magnetic materials have increasingly become indispensable in modern society. Their application fields are related to the computer, aerospace, communication, transportation, medical care and green energy and energy-saving devices such as wind power, air conditioning compressors. The magnetic energy level of sintered NdFeB is 512KJ/m3 according to the current theory. Domestic enterprises have produced magnets with magnetic energy levels between 358-382KJ/m3 in big quantities and that with 398KJ/m3 in small quantities, and continue to narrow the gap with foreign manufacturers. Because of the backward of equipments and technology, the stability and consistency in magnetic performance need to be improved further.The hard magnetic properties of NdFeB magnets primarily depend on the main phase of Nd2Fe14B (2:14:1). Adjusting the magnet main phase components can increase the intrinsic magnetic parameters and optimizing the microstructure of magnet grains can improve hard magnetic properties.This thesis based on experiments that adopt widely used the SC (strip casting) process to treat the molten alloy bodies. By pouring the molten alloy to a fast rotating water-cooled copper roller, the alloy can be crystallized into chips with thickness of 0.28mm-0.35mm by rapid cooling.α-Fe did not appear in the alloy that can make the ratio of the magnet alloy composition close to the main phase of Nd2Fe14B, and the lumpish Nd-rich phase did not appear. The microstructure of chips by the SC meets requirements of the high performance NdFeB magnets.The mechanism of the coercivity of sintered magnets is analyzed to optimize the material composition; The influences of hydrogen decrepitation and jet milling powder in current producing process on the final magnetic properties and structure of magnets. In addition, the influence of added elements on the special requirements of magnetic properties of magnets is also discussed.
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