The　effect　of　Fe-rich　content　on　the　microstructure,　phase　structure,　elements　distribution,　and　magnetic　properties　of　Sm(Co0.91-xFexCu0.07Zr0.02)7.6　(x　=　0.22,　0.30,　and　0.35)　magnets　has　been　investigated　systematically.　With　the　increase　of　Fe　content,　the　2:17H,　2:17R,　and　1:3R　phases　appeared　in　the　Fe-rich　solid　solution.　The　different　phase　structures　in　the　high-resolution　transmission　electron　microscopy　(HRTEM)　images　showed　a　locally　short-range　ordered　state　with　dislocations.　The　presence　of　2:17R　phase　and　1:3R　phase　was　negative　to　the　spinodal　decomposition　during　the　aging　stage.　In　addition,　the　high　Fe　content　caused　Cu　element　enrichment　in　some　area　of　the　final　state　magnet,　which　further　affected　the　formation　of　cellular　structure.　The　Fe　content　increased　from　x　=　0.22　to　x　=　0.35,　the　average　cell　size　increased　from　83.67　to　112.46　nm,　the　thickness　of　cell　boundary　increased　from　9.6　to　18.25　nm,　and　the　density　of　Zr-rich　platelets　increased　from　0.036　to　0.06　nm.　Furthermore,　the　defective　cellular　structures　in　the　magnet　(　x　=　0.35)　with　incomplete　and　discontinuous　cell　boundaries　had　weak　pinning　field　and　poor　coercivity.　Moreover,　the　magnetooptical　Kerr　optical　microscope　observation　revealed　that　the　domain　width　of　magnet　(　x　=　0.35)　was　significantly　higher　than　that　of　magnet　(　x　=　0.22),　and　the　reversal　magnetic　domain　was　formed　first　in　the　magnet　(　x　=　0.35),　which　caused　a　poor　coercivity.　©　1965-2012　IEEE.