Abstract: According to the invention, a metal workpiece made by additive manufacturing is subjected, following the additive manufacturing process, to a cold treatment in which the workpiece is cooled to a lower target temperature of less than minus 30° C. in a cooling phase and is then heated up to an upper target temperature in a heating phase. The cold treatment significantly improves the properties of the workpiece in respect of the mechanical quality thereof.

Abstract: The invention relates to a device for the additive manufacturing of workpieces under protective gas, which device is provided with a manufacturing chamber designed as a pressure chamber, said manufacturing chamber being fluidically connected to a pressure container via a gas extraction line, which is provided with a vacuum pump, and via a gas return line. After the manufacturing of a first workpiece, the protective gas present in the manufacturing chamber is evacuated, temporarily stored in the pressure container and, prior to the manufacturing of a second workpiece, is introduced into the manufacturing chamber.

Abstract: The invention relates to a method for additive manufacture of a workpiece under protective gas, wherein a workpiece is assembled from a sequence of workpiece contours, each of which is manufactured by selective sintering or melting of a powdery or wire-like material by applying an energy beam thereto, wherein a workpiece contour is manufactured under the effect of a protective gas consisting of carbon dioxide and an inert gas. According to the invention, the chemical composition of each workpiece contour is modified according to a specified program by variation of the composition of the protective gas. Heat treatment occurring after manufacture of the workpiece contour provides for defined mechanical and technological quality values of the workpiece contour. A workpiece having zones with defined mechanical and technological quality values is produced in this manner.

Abstract: When welding with a consumable wire electrode, current contacting occurs when the electrode wire passes by a readily electrically conductive contact element. In order to improve the current contacting and reduce the wear of the contact element in particular, the invention proposes subjecting contact elements to a cold treatment prior to using same. The cold treatment has a cooling phase during which the temperature of the contact element is reduced to a lower target temperature, a subsequent holding phase in which the contact element is substantially held at the target temperature, and a final heating phase, in which the contact element is brought to an upper target temperature. The use of contact elements treated using the method according to the invention leads to a substantial increase of the wear resistance compared to untreated contact elements.

Abstract: According to the invention, a metal workpiece made by additive manufacturing is subjected, following the additive manufacturing process, to a cold treatment in which the workpiece is cooled to a lower target temperature of less than minus 30° C. in a cooling phase and is then heated up to an upper target temperature in a heating phase. The cold treatment significantly improves the properties of the workpiece in respect of the mechanical quality thereof.

Abstract: In a method for manufacturing metallic components by means of generative production, a layer of metal powder is selectively melted or sintered by being exposed to an energy beam in an evacuated radiation chamber. When the radiation chamber is subsequently flooded with a cooling gas, the melted or sintered part solidifies to form a solid contour. Instead of the previously common practice of using helium, which is expensive and not readily available, as the cooling gas, it is proposed according to the invention to use a gas that contains hydrogen. Hydrogen has a higher thermal conductivity than helium and does not impair the surface of the workpiece, or only to a negligible extent.