Laser-supported process for cleaning a surface

US6419996B2 · kind B2 · utility

Assignee

• Laser- und Medizin Technologie GmbH · DE

Inventors

• Gerhard Mueller · Freilassing, DE
• Thomas Fricke · Berlin, DE

Key dates

• Filing date: Nov 12, 1998
• Grant date: Jul 16, 2002
• Expiry date: Nov 12, 2018

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B23K26/146
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

A process to remove a surface layer from a substrate by irradiating laser radiation, wherein the surface is scanned sequentially with the laser radiation being concentrated to a focus, before irradiating a predetermined surface element a thin fluid film or a fluid droplet cover is applied which covers at least that surface element, and the laser beam influences the surface element only for a very short treatment interval, especially less then 10 ms. By appropriate choice of the process parameters power density, treatment interval length, thickness of the fluid film, surface adhesion of the fluid, absorption characteristics of the fluid for the effective laser wavelength, and absorption characteristics of the fluid vapor an explosive evaporation of the fluid film is effected which results in a flaking of the surface and an evaporation of loose residues of the surface layer.