Method of effecting gamma phase precipitation to produce a monocrystalline growth in permanent magnets

Claim 1

THE PROCESS OF PRODUCING MONOCRYSTALLINE STRUCTURE IN A NORMALLY POLYCRYSTALLINE MAGNET CASTING OF IRON-NICKEL-ALUMINUM TYPE PERMANENT-MAGNET ALLOY, WHICH COMPRISES ENRICHING A THIN LAYER OF THE MAGNET CASTING AT ONE FACE THEREOF WITH A COMPONENT WHICH IS A GAMMAPHASE PRECIPITANT AND STABILIZER, TO FORM IN SUCH LAYER A COMPOSITION IN WHICH GAMMA-PHASE PRECIPITATE WILL FORM AND WILL REMAIN STABLE AT RECRYSTALLIZATION TEMPERATURE, SUBJECTING THE CASTING TO SUBSTANTIALLY UNIFORM HEATING AT A TEMPERATURE AND FOR A TIME SUFFICIENT TO INDUCE GAMMA-PHASE JPRECIPITATION IN SAID LAYER IN AN AMOUNT SUFFICIENT TO PRODUCE CRITICAL STRAIN IN THE LAYER, SUBJECTING THE CASTING, WITH THE GAMMA-PHASE PRECIPITATE PRESENT IN SAID LAYER TO HEATING AT A RECRYSTALLIZATION TEMPERATURE FOR A TIME SUFFICIENT TO INITIATE MONOCRYSTAL GROWTH IN SAID LAYER, AND CONTINUING SUCH RECRYSTALLIZATION HEATINT TO CAUSE SAID MONOCRYSTAL GROWTH TO PROGRESS FROM SAID LAYER INTO THE MAIN BODY OF THE CASTING.