Method for processing alloys via high-current density ion implantation

摘要

A surface processing method and power transmission component includes transforming by high current density ion implantation (high intensity plasma ion processing) a surface region of a metal alloy into a hardened surface region at a temperature that is less than a heat treating temperature of the metal alloy. The metal alloy includes between 1.5 wt % and 15 wt % Ni, between 5 wt % and 30 wt % Co, up to 1.0 wt % carbon, and up to 15 wt % of a carbide-forming element, such as molybdenum, chromium, tungsten, vanadium or combinations thereof, that can react with carbon to form metal carbide precipitates of the form M₂C. The surface processing temperature, vacuum pressure, precursor gas flow and ratio, and time of processing are controlled to provide a desirable hardened surface region having a gradual transition in nitrogen concentration. A vapor deposition process deposits an amorphous hydrogenated carbon coating on the hardened surface region of the metal alloy. An intermediate coating between the coating and the hardened surface region promotes adhesion between the coating and hardened surface region.