Abstract: The invention relates to a laser machining equipment including a laser oscillator (1) for generating a laser beam, a laser head (3) through which the laser beam passes, an optical path (2) for conveying the laser beam between the laser oscillator (1) and the laser head (3), and a gas source (9) fluidly connected to the laser head (3) via a main gas pipe (8). In addition, a second pipe (18) fluidly connects the gas source (9) to the laser oscillator (1). The equipment therefore comprises a common gas source for the laser oscillator (1) and head (3). The gas is preferably nitrogen.

Abstract: A method for the hybrid laser-arc welding of several metal workpieces. The welding process uses at least one laser beam and at least one electric arc. The metal workpieces are stacked in a multiple-thickness configuration and the laser beam and the electric arc are used to weld the edges of the multiple-thickness configuration.

Abstract: The invention concerns a method for cutting a metal or metal alloy workpiece using at least a laser beam and at least an assist gas of said laser beam wherein the assist gas consists of a mixture of helium and argon and/or nitrogen or of nitrogen and oxygen and the cutting speed is faster than 15 m/min. The thickness of the workpiece to be cut ranges between 0.5 mm and 10 mm, preferably more than 0.5 mm. The workpiece to be cut is selected among plates, metal sheets and tubes. The laser beam is delivered by a CO2 type or YAG:Nd laser device.

Abstract: The invention concerns a hybrid arc-laser method for welding metal parts, such as a tube or tailored blanks by producing at least a weld joint between edges to be welded and by using a laser beam and an electric arc combined with each other so as to melt and subsequently solidify the metal along said edges to be welded.

Abstract: A hybrid welding process combining a laser beam and an electric arc, in particular a plasma arc, using special gases or gas mixtures as electric arc striking gases and shielding gases, and to its application to the welding of pipes or tubes or to the welding of tailored blanks, especially those that can be used in the automobile industry.

Abstract: The invention concerns a method for cutting a metal or metal alloy workpiece using at least a laser beam and at least an assist gas of said laser beam wherein the assist gas consists of a mixture of helium and argon and/or nitrogen or of nitrogen and oxygen and the cutting speed is faster than 15 m/min. The thickness of the workpiece to be cut ranges between 0.5 mm and 10 mm, preferably more than 0.5 mm. The workpiece to be cut is selected among plates, metal sheets and tubes. The laser beam is delivered by a CO2 type or YAG:Nd laser device.

Abstract: The invention concerns a method for welding one or several metal components to be assembled by producing at least one weld joint on said metal components to be welded, said weld joint being obtained by using a laser beam and at least an electric arc, which consists in generating said laser beam using a power-diode laser device. The invention also concerns an installation for implementing the welding method. The invention is useful for welding abutted flanks designed to constitute at least part of a motor vehicle body component.

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.

Abstract: Apparatus and method for cutting a workpiece by the use of a laser beam and an assist gas, in which at least one optical means is used to focus the laser beam at several focal points separate from one another, and in which, as assist gas for the said laser beam, a gas mixture containing hydrogen and at least one inert gas is used. The optical means is transparent or reflecting and is chosen from lenses, mirrors and combinations thereof, preferably a bifocal lens. The workpiece to be cut is made of stainless steel, coated steel, aluminum or an aluminum alloy, non-alloy steel or alloy steel. The inert gas is chosen from nitrogen, argon, helium and mixtures thereof.

Abstract: Method and apparatus for cutting a workpiece made of stainless steel, coated steel, aluminum or aluminum alloy by the use of a transparent or reflecting optical means for focusing a laser beam and of an assist gas for said laser beam. The optical means is of the multifocus type and is chosen from lenses, mirrors and combinations thereof. The assist gas is oxygen or a nitrogen/oxygen mixture containing at least 90% nitrogen. The method of the invention makes it possible to increase the cutting performance by 40% compared with a conventional laser cutting method.

Abstract: A process and a device for the gas-shielded MIG welding in modulated-spray mode, of aluminum, particularly aluminum alloys, or stainless steels, in which the current is modulated at a modulation frequency of less than 60 Hz. The shielding gas contains at least 90% helium, argon or a mixture thereof and at most 1.95% of at least one minor gaseous component chosen from oxygen and carbon dioxide. This process allows effective degassing of most of the diffusible hydrogen liable to be found in the pool of molten metal and improves the appearance and quality of the weld beads thus produced on workpieces or equipment intended for the rail, sea, air, road or space transport industry or for the chemical, petrochemical, electronic, nuclear or agrochemical industries.