Geneva, Switzerland – The World Intellectual Property Organization (WIPO) has assigned a patent to Aktiebolaget SKF, Goteborg, Sweden, for a bearing component manufacturing method using laser marking. The inventors are listed as John Van den Sanden, Johannes Hendrik Krock, and Anne Hendrik Mol.
The abstract posted by the WIPO is: The present invention relates to a method of manufacturing a bearing component, in which a visible identification mark is created on a surface of the component using a laser beam. The laser marking creates an oxidized layer on the component surface and, in an underlying region, alters the microstructure of the bearing steel from which the component is made. According to the invention, the mark is then rendered visually undetectable with the naked eye by removing at least the oxidized surface layer of the mark. This exposes the altered microstructure, which is revealable by applying an etchant to the visually undetectable mark.
The patent was filed on Dec. 22, 2009, under Application No. PCT/EP2009/009209.