The　waste　VCM　magnets　were　disassembled　from　hard　disk.　After　removing　the　coating　of　nickel　by　electrochemical　method,　the　waste　VCM　magnets　were　recycled　by　grain　boundary　diffusion　with　DyH3　nano-particles.　Compared　to　that　of　the　original　magnet,　the　coercivity　of　recycled　magnets　increases　by　11.81　kOe,　while　the　remanence　keeps　almost　invariant.　investigation　shows　that　Dy　is　preferentially　enriched　as　(Nd,Dy)(2)Fe14B　phase　in　the　surface　region　of　the　Nd2Fe14B　matrix　grains　indicated　by　the　remarkable　enhancement　of　the　magneto-crystalline　anisotropy　field　of　the　magnet.　As　a　result,　the　magnet　diffused　with　a　small　amount　of　DyH3　nano-particles　possesses　enhanced　coercivity　without　remarkably　sacrificing　its　magnetization.　(C)　2015　Elsevier　B.V.　All　rights　reserved.