Abstract: Apparatuses and methods for material processing are disclosed. In an embodiment, an apparatus may include a source of electromagnetic radiation that emits the radiation in a beam with a defined power density distribution and beam-shaping optics variably shaping and focusing the radiation of the beam source. An optical axis of the radiation may be directed onto a processing zone. The apparatus may also include means for holding the radiation in a region wherein the radiation interacts with a material forming and moving in the processing zone; as well as an adjusting device that varies the second beam parameter product by changing at least one of a position and an optical property of at least one optical element.

Abstract: 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.

Abstract: 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.

Abstract: 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 I0f (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.

Abstract: A method for connecting two or more components including overlapping surface sections via a laser beam. In the method, prior to the laser welding, the components are fixed in a positive fit to at least one of the overlapping surface sections by local cold joining, preferably via rivets or screws and are then laser welded, a laser weld seam being created in close proximity to each fixing point that has been produced by cold joining, in particular as close as possible to the rivet or screw.

Abstract: A method and device for the 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 I0f(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. With this method the respective incident angles ? of the removal face, formed by the normal vectors n at the removal face, and the directions of the Poynting vectors are set in such a way that they do not exceed a maximum value ?max in a predefined region around the apex of the removal face.

Abstract: A method and device for machining material uses laser radiation, in which the unfocused laser radiation is focused through a focusing optics to a smaller beam cross section. The optical axis of the focused laser radiation, referred to as beam axis, is directed at the material surface. The beam waist, which results from the focusing operation, of the focused laser radiation is held in the region of the interface, which forms of laser radiation and material. The laser radiation is partially absorbed on the interface such that due to induced material removal or induced material displacement the interface and thus also the laser radiation penetrate into the 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.

Abstract: An embodiment of the present invention discloses a method for connecting two or more components including overlapping surface sections via a laser beam. In the method, prior to the laser welding, the components are fixed in a positive fit to at least one of the overlapping surface sections by local cold joining, preferably via rivets or screws and are then laser welded, a laser weld seam being created in close proximity to each fixing point that has been produced by cold joining, in particular as close as possible to the rivet or screw.

Abstract: 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.

Abstract: In a method for machining workpieces by combining a first machining tool with at least one second machining tool, wherein at least one of the first and second machining tools employs laser radiation, the first machining tool is operated with a first pulse modulation and the at least one second machining tool is operated with a second pulse modulation. The first and second pulse modulations are synchronized. Same pulse frequencies can be used for the first and second pulse modulations, or, in the alternative, pulse frequencies are used that are an integral multiple relative to one another, wherein the first and second pulse modulations are in a fixed or variably controlled phase relationship relative to one another.

Abstract: A method for processing moving workpieces with laser radiation that is focused on a to-be-processed workpiece surface by means of a laser beam that is moved but not relative to the workpiece. The laser beam is focused in a line-like manner and its beam spot corresponds practically exclusively and with full a real coverage to the work piece surface to be processed.

Abstract: A nozzle assembly for laser beam cutting has a nozzle body shaped like a ncated cone fitting the focussed laser beam and surrounding the same. The assembly has a passage bore for the laser beam, with a nozzle sleeve concentrically surrounding the nozzle body and forming an annular gap therewith. An outlet bore is coaxial with the passage bore for a cutting gas stream from an annular gap connected to a gas source. The outlet bore is located on the workpiece side in front of the passage bore and has a diameter (D) exceeding the diameter (d) of the passage bore. In order to insure that the deflection of the gas stream from the nozzle takes place parallel to the axis of the laser beam, with a minimum of flow loss, the nozzle assembly is built so that the outlet cross section of the outlet bore is approximately the same as the transition cross section of the annular gap to the outlet bore.

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.

Abstract: The disclosure involves an apparatus (1) for the flying-shear cutting of thin-layer material, reeled off from a coil, by laser radiation, especially metal strips, fabrics, synthetic resins, paper, cardboard, and composite materials. In order to be able to crosscut individual strip sections (17) at high speeds without having to arrest the strip (2), the apparatus (1) consists of a traverse (3) arranged at an angle to the travel direction (a) of the strip (2), this traverse being rotatably supported and driven about its longitudinal axis of symmetry (4). Mutually opposed guides (5) for two separately operable laser cutting heads (6) with nozzles (7) are mounted in parallel to the longitudinal axis of symmetry (4) of the traverse (3). The laser cutting heads (6) are in each case movable separately or individually by way of the guides (5).

Abstract: A process for treating workpieces by means of laser radiation, particularly or the cutting, hole burning and material removal with respect to metallic workpieces, in which the treated site of the workpiece is monitored by a radiation detector which contributes to reducing the intensity of the laser radiation when an upper limit value is reached and to increasing it when a lower limit value is reached.