Method of manufacturing a bearing component with visually undetectable mark; bearing component with such marking; method of authentification such marking

摘要

The present invention relates to a method of manufacturing a bearing component, in which a visually undetectable identification mark is created on a surface of the component by means of laser marking performed in a protective gas environment. The protective gas environment prevents the formation of a visible oxide layer, while the temperatures induced at the component surface and below the component surface, due to the laser marking, are sufficient to alter the microstructure of the bearing steel from which the component is made. The altered microstructure is revealable by applying an etchant to the visually undetectable mark, thereby allowing authentication of the bearing component.

主权项

1. A method for providing an identification mark on a bearing component made from a bearing steel, comprising:
hardening the bearing component; placing the bearing component in a protective gas environment; and while in the protective gas environment, applying a laser beam to a surface of the bearing component so as to raise a temperature of a depth of 0.05-0.3 mm below the surface to between 200-500° C. so as to alter the microstructure of the bearing steel but without melting the surface, wherein no oxidised surface layer forms on the surface and a tempered zone forms at and below the surface, which tempered zone is the identification mark and is visually undetectable with the naked eye.