METHOD FOR PREPARING A CARBON ALLOY FROM NITRIDES AND / OR NITRIDE-CARBIDE MIXTURES AND / OR CARBONITRIDES AND ALLOYS OF AT LEAST ONE METAL IRON, COBALT AND NICKEL, AS WELL DESTRIVED.

摘要

1329729 Sintered carbonitride bodies UGINECARBONE 28 Sept 1970 [30 Sept 1969] 46076/70 Headings C7A and C7D Sintered alloy consists of 65-97% of a hard phase of which at least 35% is at least one carbonitride of transition metals of groups IVa and Va of the Periodic Table containing less than 0À15% oxygen any balance being one or more metal carbides in free state or as solid solution, and 3-35% of a binding agent consisting predominantly of at least one of the metals Fe, Co and Ni and at least one of the metals Cr, Mo and W. The carbonitride may be deoxidized by annealing a powder mixture thereof with 0À5-5% of Cr, Mo or W powder at 1500-1800‹C. under N 2 at reduced pressure (e.g. 50-300 mm Hg). Exemplary binder alloys preferably contain 5-40% of Cr, Mo or W and may contain Ti or Al. Decomposition of the carbonitride during heating (e.g. during refining or sintering) may be counteracted by increasing the nitrogen pressure to 1-30 atmospheres towards the end of the heating.