THIN-WALLED R-Fe-B GROUP SINTERED MAGNET AND MANUFACTURING METHOD THEREOF

PROBLEM TO BE SOLVED : To manufacture a small thin-walled working free sintered magnet useful for a motor or an actuator and having suppressed magnetic characteristics manufactured with high dimension accuracy, by suppressing an reaction between carbon and oxygen contained in a binder and a reaction between carbon and oxygen in a degreased/sintering furnace while reducing cost in a molding process/machining process by employing extrusion molding. SOLUTION : A thin-walled R-Fe-B group sintered magnet (R is a rare-earth element containing one or more kinds of Y) has an R amount of 32.5-37.5 mass%, is the planar shape of a thickness of 1mm or less, and has an oxygen content of 1.00 mass% or less and a carbon content of 0.10 mass%.