Process for producing alloys containing chromium and dispersed refractory metal oxide particles

Claim 1

IN A PROCESS FOR PRODUCING METAL ALLOY COMPOSITIONS CONTAINING CHROMIUM IN WHICH ALLOY REFRACTORY METAL OXIDE PARTICLES ARE DISPERSED, THE STEPS COMPRISING (1) PREPARING A MIXED OXIDE POWDER CONTAINING (A) CHROMIUM OXIDE, (B) AN OXIDE OF A METAL SELECTED FROM THE GROUP CONSISTING OF IRON, COBALT AND NICKEL, AND (C) A REFRACTORY OXIDE IN THE FORM OF PARTICLES LESS THAN 0.25 MICRON IN DIAMETER, AND HAVING A FREE ENERGY OF FORMATION AT 1000* C. ABOVE 90 KILOCALORIES PER GRAM ATOM OF OXYGEN IN THE OXIDE, (2) MIXING WITH SIAD POWDER UP TO ONE GRAM ATOM OF CARBON PER GRAM ATOM OF OXYGEN COMBINED WITH THE CHROMIUM IN SAID CHRMIUM OXIDE, (3) HEATING THE MIXTURE AT A TEMPERATURE IN THE RANGE FROM 850*C. TO 1050* C. IN AN ENVIRONMENT SELECTED FROM VACUUM AND A FLOWING STREAM CONSISTING OF AT LEAST ONE GAS OF THE GROUP CONSISTING OF PURE DRY HYDROGEN, ARGON, HELIUM AND NEON, WHEREBY CARBON MONOXIDE GAS IS EVOLVED, AND CONTINUING SAID HEATING UNTIL THE CARBON MONOXIDE IN SAID ENVIRONMENT IS BELOW 1000 P.P.M., AND (4) THEREAFTER HEATING THE MIXTURE IN CONTACT WITH FLOWING HYDROGEN AT A TEMPERATURE IN THE RANGE OF 900 TO 1200*C. UNTIL THE DEW POINT OF THE EFFLUENT HYDROGEN IS BELOW - 30*C.