Process for the laser beam cutting of strip or plate workpieces, especially magnetic steel sheets

US5578228A · kind A · utility

Assignee

• Thyssen Stahl AG · DE

Inventors

• Eckhard Beyer · Alsbach, DE
• Kai-Uwe Preissig · Dortmund, DE
• Dirk Petring · Kerkrade, NL
• Dieter Bingener · Kreuztal, DE
• Hans-Dieter Riehn · Gladbeck, DE

Key dates

• Filing date: Apr 3, 1995
• Grant date: Nov 26, 1996
• Expiry date: Apr 3, 2015

Classification

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

Abstract

The laser beam melts a plate or strip workpiece with the formation of a vapor capillary at a cutting point and the melt is driven off by a cutting gas consisting of a mixture of inert gas and hydrogen gas, the hydrogen gas making up to 25% by volume of the cutting gas. In order to maintain the vapor capillary, the cutting gas is taken to the surface of the melt at the cutting point at such a pressure and with such a pressure distribution that the temperature at the surface of the melt is kept at boiling point and the melt is continuously driven out of the cutting seam in the side away from the cutting direction of the vapor capillary. The plate or strip workpiece can be a magnetic steel sheet. An additional stream of gas, liquid, or solid particles can be used to move melt out of the cutting seam.