US Patent 7153377 Method of separating admixed contaminants from superalloy metal powder

A method is provided for separating superalloy metal powder from contaminants, such as process-produced contaminants, by enhancing the magnetic properties thereof in a carburizing atmosphere followed by magnetic separation of the contaminants from the superalloy metal powder to thereby enhance the concentration of the contaminants. Heating or mechanical agitation or both are employed to resist agglomeration of the metal powder before magnetic separation thereof from the contaminants. Certain preferred times and temperatures are disclosed.