Diffusion source slurry for neodymium-iron-boron magnet as well as preparation method and application of diffusion source slurry

The invention discloses diffusion source slurry for a neodymium-iron-boron magnet as well as a preparation method and application of the diffusion source slurry. The preparation method comprises the steps that smelting and sheet throwing are conducted according to the proportion of all elements of the chemical formula RElaRE2bRE3cMldM2e, and the multi-component alloy rapid hardening sheet is prepared; performing jaw crushing and rolling ball milling treatment on the multi-component alloy rapid hardening sheet to obtain diffusion source coarse powder; performing jet milling treatment on the diffusion source coarse powder to obtain diffusion source fine powder; and mixing the diffusion source fine powder with an organic solvent and a glue agent to obtain the diffusion source slurry. Compared with a traditional industrial line diffusion source slurry process, the improved diffusion source components and the specific diffusion source slurry preparation process are adopted, the brittle phase is increased, the acti