Method for producing a metal surface

A method for producing a surface on a metallic part which has a coarse structure of elevations in the form of ribs and of depressions in the form of grooves with a width of 2 mm to 0.4 mm comprising

• in a first step, coating the metallic surface with an adhering, electrochemically effective protective lacquer layer which can be removed by means of a laser of a selected wavelength at a sufficiently low energy density that a significant energy threshold exists with respect to the energy density required for an ablation of the metal to prevent an ablation of the metal,
• in a further step, inscribing furrows into the protective lacquer with the laser corresponding to centerlines of envisaged grooves, a width of the furrows amounting to only a fraction of the widths of the envisaged grooves,
• in a further step, exposing the surface provided with furrows in the protective lacquer to an electrically conductive fluid to form the grooves which simultaneously grow in depth and in width parallel to the surface in a region of the furrows by means of electrochemical erosion and/or etching for a limited time, and
• in a further step, removing the remaining protective lacquer.