HIGH PERFORMANCE IRON-BASED RARE EARTH PERMANENT MAGNET MATERIALS

THIS PROPOSAL ADDRESSES THE PROBLEM OF SYNTHESIZING AND DEVELOPING NEW PERMANENT MAGNET MATERIALS FOR USE AT TEMPERATURES GREATER THAN 300 OC. THE RECENT SYNTHESIS OF A NEW COMPOUND, SM2FEI7N3-Y, WITH A STRONG UNIAXIAL ANISOTROPY, A LARGE SPONTANEOUS MAGNETIZATION, A POTENTIAL ENERGY PRODUCT, OF ABOUT 60 MGOE, AND A CURIE TEMPERATURE, TC, OF 476 OC SUGGESTS THE POSSIBILITY OF ACHIEVING COST--EFFECTIVE, HIGH PERFORMANCE MATERIALS NEEDED TO SATISFY THE REQUIREMENTS OF A VARIETY OF MILITARY AND COMMERCIAL DEVICES. SUBSTITUTION OF OTHER ELEMENTS FOR IRON CAN PRODUCE A T OVER 725 OC AND OFFERS THE OPPORTUNITY FOR PRODUCING MAGNETS FOR USE AT TEMPERATURES GREATER THAN 300 OC. SOME APPLICATIONS INCLUDE TRAVELING WAVE TUBES, MOTORS AND GENERATORS THAT MUST OPERATE AT ELEVATED TEMPERATURES. A BRIEF BACKGROUND DISCUSSION COMPARES THE NEW MATERIAL WITH OTHER RARE EARTH MATERIALS THAT HAVE BEEN DEVELOPED IN THE LAST TWO DECADES. A PROGRAM IS PROPOSED FOR USING PARTICULAR SUBSTITUENTS TO ENHANCE BOTH THE CURIE TEMPERATURES OF THESE NEW NITRIDED SMFE-BASED MATERIALS. EMPHASIS IS GIVEN TO DEVELOPING PROCESSING PROCEDURES FOR CONSOLIDATING THE MATERIALS INTO FULLY DENSE PERMANENT MAGNET STRUCTURES THAT WILL HAVE REMANANCES CORRESPONDING TO THEIR SATURATION MAGNETIZATIONS.