Bearings constituted by a nitrided steel having a high surface and core hardness, and their manufacture

摘要

544,277. Alloys; annealing; cementation. CLEVELAND, F. J. (Soc. Anon. Officine di Villar Perosa). May 18, 1940, No. 8885. [Classes 72 and 82 (i)] Roller bearings or parts thereof such as balls, rollers, needles, rings, and races, are made from steel containing 0.5-1.5 per cent. of carbon, 4-8 per cent. of chromium, 3-10 per cent. of molybdenum, and 0.5-1.5 per cent. of vanadium. The articles are hardened in oil at about 1175‹C. and nitrogenized at about 500‹C. during 100 or more hours.