In　order　to　prepare　high-performance　low-cost　sintered　(Nd,　MM)-Fe-B　magnets,　the　effect　of　the　microstructure　of　strip-casting　alloys　on　the　particle　size　and　distribution　of　powder　was　first　investigated　in　this　work.　By　adding　lubricant　and　antioxidant　to　improve　orientation　and　control　oxygen　content,　the　mischmetal-based　sintered　magnet　possessing　fine　grains　(similar　to　2.5　mu　m)　along　with　smooth　and　continuous　grain　boundaries　could　maintain　the　excellent　magnetic　properties　of　B-r　=　12.31　kG,　H-cj　=　9.61　kOe　and　(BH)(max)　=　36.52　MGOe　by　optimizing　two-stage　annealing　temperature.　The　magnet　prepared　in　this　work　exhibits　record-high　magnetic　properties　in　the　same　proportion　of　MM　substitution,　which　provides　useful　guidance　for　the　preparation　of　MM　doped　magnets.　(C)　2020　Elsevier　B.V.　All　rights　reserved.