Sintered cobalt-rare earth intermetallic product

Claim 1

A SINTERED PRODUCT HAVING SIGNIFICANTLY ENHANCED PERMANENT MAGNET PROPERTIES WHICH ARE SUBSTANTIALLY STABLE IN AIR AT ROOM TEMPERATURE CONSISTING ESSENTIALLY OF COMPACTED PARTICULATE COBALT-RARE EARTH ALLOY CONSISTING ESSENTIALLY OF A CO5R INTERMETALLIC PHASE AND A COR INTERMETALLIC PHASE WHICH IS RICHER IN RARE EARTH METAL CONTENT THAN SAID CO5R PHASE, SAID CO5R INTERMETALLIC PHASE BEING PRESENT IN AN AMOUNT OF AT LEAST 65% BY WEIGHT OF SAID SINTERED PRODUCT AND SAID COR INTEMETALLIC PHASE WHICH IS RICHER IN RARE EARTH CONTENT THAN SAID CO5R PHASE BEING PRESENT IN A POSITIVE AMOUNT HAVING A VALUE RANGING UP TO 35% BY WEIGHT OF SAID PRODUCT, WHERE R IS A RARE EARTH METAL OR METALS, SAID SINTERED PRODUCT HAVING A DENSITY OF AT LEAST 87 PERCENT OF THEORETICAL AND HAVING PORES WHICH ARE SUBSTANTIALLY NON-INTERCONNECTING AND THE COMPOMENT GRAINS HAVE AN AVERAGE SIZE LESS THAN 30 MICRONS, SAID SINTERED PRODUCT BEING PRODUCED BY ADMIXING PARTICLES OF A BASE COBALT-RARE EARTH METAL ALLOY AND AN ADDITIVE COBALT-RARE EARTH METAL ALLOY, SAID PARTICLES HAVING AN AVERAGE SIZE RANGING UP TO ABOUT 10 MICRONS, SAID BASE ALLOY EXISTING AT SINTERING TEMPERATURE AS A SOLID CO5R INTERMETALLIC PHASE AND SAID ADDITIVE ALLOY BEING A SOLID AT SINTERING TEMPERATURE AND BEING RICHER IN RARE EARTH METAL CONTENT THAN SAID BASE ALLOY, SAID BASE ALLOY AND SAID ADDITIVE ALLOY EACH BEING USED TO FORM A MIXTURE WHICH HAS A COBALT AND RARE EARTH METAL CONTENT SUBSTANTIALLY CORRESPONDING TO THAT OF THE FINAL SINTERED PRODUCT WITH SAID ADDITIVE ALLOY BEING PRESENT IN AN AMOUNT OF AT LEAST 0.5 PERCENT BY WEIGHT OF SAID MIXTURE, PRESSING SAID MIXTURE INTO A GREEN BODY, AND SINTERING SAID GREEN BODY IN A SUBSTANTIALLY INERT ATMOSPHERE TO PRODUCE SAID SINTERED PRODUCT.