R-T-B based permanent magnet and method for manufacturing same

An R-T-B based permanent magnet in which R represents one or more rare earth elements and essentially includes Nd and/or Pr, T represents one or more iron group elements and essentially includes Fe, and B represents boron, wherein the iron group elements refer to Fe, Co and Ni;

• wherein
• the R-T-B based permanent magnet includes M which is one or more selected from Ga, Al, Cu, and Si;
• and
• the R-T-B based permanent magnet comprises main phase grains made of R2T14B crystals and two-grain boundaries existing between two adjacent main phase grains,
• a carbon amount is 0.020 mass % or more and 0.080 mass % or less with respect to 100 mass % of the R-T-B based permanent magnet as a whole,
• an amount of heavy rare earth elements is 0 mass % with respect to 100 mass % of the R-T-B based permanent magnet as a whole,
• a residual magnetic flux density of the R-T-B based permanent magnet is 1435 mT or more,
• a coercivity of the R-T-B based permanent magnet is 1230 kA/m or more,
• an average thickness of the two-grain boundaries is 5 nm or more and 50 nm or less,
• and an area ratio of R6T13M compounds in an arbitrary cross section is 0.50% or less, including 0%.