Cost-saving and efficient grain boundary diffusion technology

By utilizing grain boundary diffusion technology to selectively introduce heavy rare earth elements on the surface of main phase grains, it is possible to effectively suppress the nucleation of demagnetization domains during the demagnetization process, thus significantly improving the intrinsic coercivity of the magnet while sacrificing only a small amount of residual magnetism.

GIASTAR MAGNET has broken through the technical bottlenecks of conventional diffusion processes in terms of diffusion depth, consistency of element distribution, and corrosion resistance through multi-element diffusion source component design, high diffusion flux substrate modification, diffusion heat treatment process adjustment and other technologies.

Grain Size Reduction Technology, GSRT

Through advanced powdering technology, combined with a strict oxygen control process throughout the entire production process, we have effectively solved the manufacturing challenges caused by grain refinement, achieving large-scale production of fine-grained magnets.

By using the latest airflow milling equipment, powders with an average particle size of approximately 3.0μm are produced. Reducing the size of the main phase grains in sintered neodymium iron boron magnets can effectively improve the intrinsic coercivity of the magnet. Grain refinement can decrease the defect concentration on the surface of the main phase grains, weaken the stray field intensity inside the magnet, and suppress the formation of demagnetization domains.

Grain Boundary Modification Technology, GBMT

Through composition design and process improvement, the physical and chemical properties of the grain boundary phase in sintered neodymium iron boron magnets are optimized, achieving a new high in performance for rare-earth-free/low rare-earth magnets.

Research has found that the grain boundary phase in conventional sintered neodymium iron boron magnets exhibits ferromagnetic properties, which is advantageous for the expansion of demagnetization domains during the demagnetization process, leading to a lower coercivity of the magnet.

Constructing non-ferromagnetic grain boundaries and optimizing the distribution of grain boundary phases can effectively weaken the exchange coupling between main phase grains, slowing down the expansion rate of demagnetization domains, and thereby enhancing the coercivity of the magnet