Patent ID: 7387694

Claim:
A method of making an air-hardened steel roll bearing part or component, wherein said method comprises the steps of making air-hardened steel with a composition comprising: from about 0.31% to about 0.85% by weight carbon, from about 0.95% to about 2.10% by weight silicon, from about 1.15% to about 1.85% by weight manganese, from about 0.00% to about 1.65% by weight chromium, from about 0.05% to about 0.20% by weight nickel, from about 0.10% to about 0.70% molybdenum, and iron; making from the air-hardened steel a semi-finished article, wherein a minimum carbon content of the semi-finished article is selected so that a minimum hardness required for use as the roll bearing part or component is provided, wherein a temperature-time behavior of the air-hardened steel permits a cooling that is sufficiently slow for formation of a martensitic structure, such that no forced cooling process must be performed; cold-forming the semi-finished article into a finished shaped roll bearing part or component with a predetermined finished shape; then hardening the finished-shape roll bearing part or component by a heat treating process, wherein no forced cooling is employed and a martensitic structure is formed; but does not include hard-working of the roll bearing part or component after said heat treating process and no further form-shaping occurs after the cold-forming.