Method and apparatus for the laser cutting of mild steel or structural steel with a multifocus optical component
First Claim
1. A method of cutting a workpiece made of alloy or non-alloy steel by the use of at least one transparent or reflecting optical means for focusing at least one laser beam and of at least one assist gas for said laser beam, wherein the optical means comprise a multifocus optical element, and the assist gas is nitrogen or a nitrogen/oxygen mixture containing at least 90% nitrogen and an oxygen content greater than 0% by volume and less than 8% by volume.
2 Assignments
0 Petitions
Accused Products
Abstract
Method and apparatus for cutting a workpiece made of structural steel or mild steel, i.e. alloy or non-alloy steels, by the use of a transparent or reflecting optical unit for focusing a laser beam, and of an assist gas for the laser beam. The optical unit is of the multifocus type and is chosen from lenses, mirrors and combinations thereof. The assist gas is nitrogen or a nitrogen/oxygen mixture. The method of the invention makes it possible to obtain a low or almost zero oxidation of the cut face and to do so while increasing the cutting performance by about 40% compared with a laser cutting method using nitrogen or a nitrogen/oxygen mixture.
59 Citations
12 Claims
- 1. A method of cutting a workpiece made of alloy or non-alloy steel by the use of at least one transparent or reflecting optical means for focusing at least one laser beam and of at least one assist gas for said laser beam, wherein the optical means comprise a multifocus optical element, and the assist gas is nitrogen or a nitrogen/oxygen mixture containing at least 90% nitrogen and an oxygen content greater than 0% by volume and less than 8% by volume.
-
11. A method for cutting a workpiece, which comprises:
-
providing a workpiece having an upper surface and a lower surface, said workpiece being made of alloy or non-alloy steel;
generating at least one laser beam;
passing said laser beam through an output nozzle;
feeding said output nozzle with an assist gas comprising nitrogen or a nitrogen/oxygen mixture containing at least 90% nitrogen and an oxygen content greater than 0% by volume and less than 8% by volume; and
focusing said laser beam through at least one transparent or reflecting multifocus optical element so as to obtain a first focusing near the upper surface, and a second focusing near the lower surface of the workpiece.
-
-
12. An apparatus for cutting a workpiece made of alloy or non-alloy steel, comprising:
-
at least one laser generator for generating at least one laser beam;
at least one output nozzle through which said laser beam passes;
at least one transparent or reflecting optical means for focusing said laser beam; and
at least one source of assist gas for said laser bean feeding said output nozzle with assist gas;
wherein;
the optical means comprise a multifocus optical element; and
the source of assist gas feeds the nozzle with nitrogen or with a nitrogen/oxygen mixture containing at least 90% nitrogen and an oxygen content greater than 0% by volume and less than 8% by volume.
-
Specification