Method for modifying the topography of coated sheet metal using a laser beam and coated sheet metal with a topographical modification of this type

US7939781B2 · kind B2 · utility

Assignee

• Daimler AG · DE

Inventors

• Wolfgang Becker · Eppstein, DE
• Jens Bühler · Stuttgart, DE
• Klaus Goth · Sindelfingen, DE
• Mike Palmer · Williston, US
• Claus-Dieter Reiniger · Winnenden, DE
• Daniel Zauner · Langenau, DE

Key dates

• Filing date: Jan 27, 2005
• Grant date: May 10, 2011
• Expiry date: Jun 15, 2027

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B23K2103/50
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

In many cases, the coating material of coated sheet metal has a significantly lower boiling point than the sheet metal material. Thus, an explosive vaporization of coating material can occur when sheet metal of this type is joined by welding, negatively affecting the quality of the connection. To improve the connection quality, narrow gaps are created by means of spacers, allowing the vaporized coating material to escape through said gaps. The spacers are created e.g. by the laser radiation of the sheet metal. The aim of the invention is to reduce the variations in distance between the sheet metal sheets by the appropriate shaping of the spacers. This is achieved by a method, in which the laser beam executes a movement comprising transverse and longitudinal components through and/or around the center of its processing surface. This creates a topographical modification with a spherical form, i.e. with an apex radius that is greater than the height of said topographical modification.