METHOD FOR THERMOCHEMICAL PROCESSING CUTTERS Russian patent published in 1994 - IPC

FIELD: mechanical engineering. SUBSTANCE: fine-threaded cutters of carbon steel are nitrocarburized in a mixture having carbamide, natural volcanic pearlite, trilon B and polyethylene being the ratio 10:1:1:4. The operating temperature is variable from 900 to 910 C. Next tempering is performed under vacuum 10^-1 mm mm mercury column for 45 - 60 min. Before laying into the above-mentioned nitrocarbonizing mixture the articles are placed into polyethylene bags. EFFECT: diffusion layers of increased depth and hardness, maintaining non-polluting ecologically clean process. 2 cl, 1 tbl