Stainless steel powder product

Abstract

Abstract A METHOD IS PROVIDED FOR PRODUCING HOT WORKABLE METAL POWDER FROM COMPOSITIONS NORMALLY DIFFICULT OR IMPOSSIBLE TO WORK. A MOLTEN METAL BATH IS ESTABLISHED OF A METAL COMPOSITION OF MELTING POINT ABOVE 1000* C. CONTAINING SUBSTANTIAL AMOUNTS OF AT LEAST ONE PHASEFORMING CONSTITUENT WHICH NORMALLY FORMS A SEGRAGATABLE PHASE ON COOLING. THE BATH IS SUBDIVIDED INTO MEDIUM TO SMALL METAL DROPLETS AND IS RAPIDLY COOLED TO A TEMPERATURE BELOW THE FREEZING POINT AT A COOLING RATE OF AT LEAST ABOUT 100* C./SEC., AND PREFERABLY FURTHER RAPIDLY COOLED TO OR NEAR ROOM TEMPERATURE. THE POWDER THUS PRODUCED, BECAUSE OF A FINE DENDRITIC GRAIN SIZE, IS ONLY SLIGHTLY IF AT ALL SEGREGATED AND ALL HARD BRITTLE PHASES ARE DISITRIBUTED AS FINE PARTICLES, MAKING THE ALLOY READILY HOT WORKABLE. EXCESS SOFT PHASES ALSO FOLLOW THE SAME HIGHLY DISPERSED DIESTRIBUTION. THUS, A PRODUCT IS PROVIDED CHARACTERIZED BY A FINE NEAR MICRON DISPERSION OF EXCESS PHASES WHICH NORMALLY SEGREGATE AND FORM AS COARSE PHASES, FOR EXAMPLE AT GRAIN BOUNDARIES, WITH RESULTANT POOR HOT WORKING PROPERTIES.

Inventors

• 👤 Nicholas J Grant

Bibliographic Details