Method of heat treating chromium-containing corrosion and/or heat resisting steels

摘要

Corrosion and/or heat-resisting alloy steels containing 1-60 per cent of chromium up to ,25 of carbon and 0,5-3,0 of titanium or niobium are heat treated, to prevent loss of corrosion resistance at temperatures below about 1470 DEG F., by heating to temperatures below 1346 DEG F. and 1740 DEG F. for 0.1-10 hours the time being sufficient to obtain a substantial conversion of the carbon content of the steel into carbides of titanium or niobium. The steels may be heated to 2150 DEG F. and quenched to room temperature before the heating described above. The heat treatment may also be applied to austenitic nickel iron alloys containing chromium carbon and titanium. In an example an alloy steel containing 0,1 per cent of carbon, about 18 of chromium, about 8 of nickel and about 0,5 of titanium is heated either for 1 hour at 1600 DEG F. or for 4 hours at 1400 DEG F. The heat treatment may be applied before or after cold rolling or fabricating. Reference has been directed by the Comptroller to Specification 394,378.