Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.v.

Advanced Technik Gmbh

Rheinisch-Westfaelische Technische Hochschule Aachen

Thyssenkrupp Drauz Nothelfer Gmbh

Thyssen Laser-Technik Gmbh

Rheinisch-Westfalische Technische Hochschule Aachen

Rheinisch-Westfälisch-Technische Hochschule Aachen

Wolfgang Schulz

Peter Abels

Dirk Petring

Stefan Kaierle

Markus Niessen

Gerd Herziger

Jorg Franke

Jan Michel

Jorg Beersiek

Frank Schneider

Eckhard Beyer

Gerhard Alber

Reinhart Poprawe

Boris Regaard

Friedrich Behr

Christian Kratzsch

George Vossen

Holger Nitsch

Jörg Neubert

Anas Moalem

Jens Schuettler

Urs Eppelt

Georg Vossen

In a method and device for machining material, an unfocused beam of laser radiation is focused and directed at the material surface, creating an interface of laser radiation and material to be machined. The beam waist, which results from the focusing the laser radiation, is held in the region of the interface of laser radiation and material. The spacing of the beam waist from the upper or lower side of the interface in the axial direction corresponds at most to triple the value of the penetration depth of the interface into the material. The focusing is effected such that components of the laser radiation are made divergent not just in the propagation direction downstream of the beam waist but also in the beam waist itself and/or also in the propagation direction upstream of the beam waist.

Method for machining material using laser radiation and apparatus for carrying out the method

The application relates to a method for determining the cut quality of a laser cutting process, said quality being assessed on the basis of the formation of solidification ridges along the cut face and/or burr formation on the lower edge of the cut face. In said method, a virtual laser cutting machine in a simulation program can be virtually operated with a set of values P0 from a parameter space P.; In a step a), the parameter set P0 is entered in the virtual cutting machine (), then in step b), a cut is made in the virtual workpiece by calculating, from partial differential equations with initial and boundary values, the progression of the melt film thickness over time and the position of the melt front at the apex of the cutting front according to the depth of the cut and the time, and then in step c), the spatial distribution of the ridge amplitude on the cut face is specified by projecting the progression of the absorption front onto the cut face and/or a spatial distribution of the burr is calculated from the progression of the melt film thickness over time and the discharge speed on the lower edge of the cut face, and in step d), a virtual cut quality is provided () for further analysis.

Method for determining the cut quality of a laser cutting process using a simulation program

This invention relates to a method for cutting materials using a laser beam, which emerges from a cutting head comprising a cutting nozzle with an inner edge, and is absorbed by the cutting front. The axis of the laser beam is displaced in relation to a workpiece along a cutting line with a fixed orientation in the cutting direction of said workpiece. In this method the position (p) of the cutting head is modulated with regard to its time averaged value, or the laser power and gas pressure in the cutting head are modulated.

Method for cutting materials using a laser beam

A method for material removal to a predetermined removal depth from a workpiece employs a laser beam consisting of one or more sub-beams, each of the latter having a defined beam axis. The axis of the laser beam or the individual axes of the sub-beams are guided along a removal line at a predetermined travelling speed and the laser beam has a predetermined spatial energy flow density that defines a Poynting vector S with a value If (x) and a direction s, the spatial energy flow density creating a removal face with an apex formed by the leading part of the removal face in the removal direction and the face, creating a removal edge.

Method for material removal and device for carrying out said method

The present invention relates to a method for measuring phase boundaries of a material during the machining of a workpiece () with a machining beam, more preferably with a laser beam, and a device that is embodied in such a way as to carry out the method. According to said method, during the machining, a machining region () containing the impact point of the machining beam () on the workpiece () is illuminated at least approximately coaxially to the machining beam () by means of additional optical radiation (). Radiation () reflected by the machining region () is detected, parallel to an incidence direction of the optical radiation () or at small angle thereto, by means of an optical detector with local resolution, in order to obtain an optical reflection pattern of the machining region (). From the optical reflection pattern, a course of at least one liquid/solid phase boundary in the machining region () is then determined in an automated manner by means of an image processing algorithm on the basis of a transition from an area containing a large-surface homogeneous area and an area containing a plurality of small-surface homogeneous areas in the optical reflection pattern.

Method for measuring phase boundaries of a material during machining with a machining beam using additional illumination radiation and an automated image processing algorithm, and associated device

In a method for cutting structural components to be joined by laser radiation that is guided by a computer-controlled manipulation system provided with a nominal path for each structural component corresponding to a joining line that is curved as a result of at least one of the structural components being three-dimensionally shaped, the structural component surfaces of the structural components including the joining line are determined measuring technologically. Based on measuring results, the nominal path corresponding to a penetration line of the structural components to be joined is calculated. A marking is formed on a first one of the structural component surfaces. When performing the cut on the structural component surface provided with the marking, the resulting cutting gap and the marking are determining measuring technologically. When a deviation of the cutting gap from the nominal path is detected, the manipulation system is controlled to correct the deviation.

Method for laser-cutting structural components to be joined

A method for materials processing by means of plasma-inducing high-energy radiation, especially laser radiation, in which the instantaneous intensity of the plasma radiation is measured at plural locations of a vapor capillary. So that the method can also be performed with perfect welding results on workpieces of very small thickness, shapes of two spaced-apart peak intensity regions, or of another type of electromagnetic radiation emitted from the vapor capillary, and of a minimum region that can be formed between these two regions of extreme values are detected metrologically, the so detected shapes of the regions of extreme values are compared with predetermined region shapes, and control of the materials processing operation takes place as a function of deviations of the detected shapes from the predetermined region shapes.

Method for shaping materials with plasma-inducing high-energy radiation

A method for treating materials with plasma-inducing high-energy radiation, especially laser radiation, where an area of vapor capillaries (,) of a work piece (,) is observed with a depth definition detecting device over the entire thickness of the work piece and time-dependent measurement of plasma radiation intensity is carried out. In order to accurately monitor the quality of material treatment, the method is implemented in such a way that the momentary plasma intensities are measured at no less than two measurement points which are parallel to an axis (,) of inducing radiation (,). Predetermined capillary parameters are assigned to the measured plasma intensities and control of the material treatment is conducted depending on the capillary geometric parameters.

Method and device for treating materials with plasma-inducing high energy radiation

Method and device for working materials using plasma-inducing laser

A method is disclosed for removing material from moving metal workpieces, particular for cutting sheet metal. It entails preheating, without melting, the surface of the workpiece to a temperature at which ignition is triggered by a combustible gas directed onto the preheated section as a jet under pressure, while burnt material from the workpiece is blown away from the cut recess thus produced. In order to achieve smooth edges on large-gauge workpieces with a relatively high feed-rate, a laser beam is also directed onto the cutting front in the cut recess.

Method and apparatus for removing material from metal workpieces moved

Method for removing material from metal workpieces moved relative to the

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Langerwehe, Germany

Wolfgang Schulz