The invention relates to
neodymium iron
boron rare-earth permanent
magnet heavy rare-earth thermal
diffusion coating liquid and a preparation method and application thereof, and belongs to the technical field of rare-earth permanent
magnet surface treatment. The
neodymium iron
boron rare-earth permanent
magnet heavy rare-earth thermal
diffusion coating liquid is prepared from the components: 25-50% of heavy rare-earth
powder, 0-5% of a penetration-promoting agent, 2-15% of a binder, 1-3% of a surfactant, 1-3% of a dispersing agent and the balance of a
diluent. The preparation method comprisesthe steps of mixing the heavy rare-earth
powder, the penetration-prompting agent and the
diluent, and adding residual raw materials. The method is applied to a
neodymium iron
boron rare-earth permanent magnet heavy rare-earth thermal
diffusion process, and the process comprises the specific steps that
surface cleaning treatment is carried out on the
neodymium iron boron rare-earth permanent magnet,
surface coating treatment is carried out by centrifugal immersion or spraying, and then
thermal expansion is carried out. According to the
neodymium iron boron rare-earth permanent magnet heavy rare-earth thermal diffusion
coating liquid, the coercive force can be greatly improved after the thermal diffusion, meanwhile, the coating efficiency is improved, the waste of the heavy rare-earth powderis reduced, and a
bottleneck of the prior coating art is broken.