Storage units 60, 70 store a first computer program calculating a flow rate of an assist gas with a linear function having a pressure of the assist gas in a processing head 35 as a variable, and a second computer program calculating a slope of the linear function with a function having a gap G from a tip end of a nozzle 36 to a surface of a workpiece W as a variable. A control unit 50 substitutes a value of the gap G into the function to calculate the slope of the linear function and substitutes the slope of the linear function and a value of the pressure of the assist gas into the linear function to calculate the flow rate of the assist gas.

A control unit performs: a control of forming a cut groove by running a first laser beam along a machining path in an in-plane direction of an upper surface of the workpiece; a control of stopping irradiation with the first laser beam when an irradiation position of the laser beam reaches a position short of an end point on the machining path; and a control of continuing ejection of gas over a first waiting time. The control unit performs: a control of irradiating the workpiece with a second laser beam that gives less thermal energy to the workpiece per unit time than the first laser beam; and a control of forming a joint portion coupling the product and the offcut by running the second laser beam in an uncut region on the machining path, the joint portion having a thickness smaller than a thickness of the workpiece.

This disclosure describes laser machining head cutting gas nozzles that include an inner nozzle having a nozzle opening configured to form a core gas flow, an outer nozzle having an annular gap surrounding the nozzle opening and configured to form an annular gas flow, and a sleeve in the annular gap, wherein the sleeve is arranged to be axially displaceable between a rearward position and a forward position, wherein the sleeve projects beyond the inner nozzle at least when in the forward position, and wherein the sleeve widens a cross-sectional area of the outer nozzle to a variable degree as the sleeve is displaced from the rearward to the forward position. Methods of using a cutting gas nozzle are also described.

This disclosure describes laser machining head gas nozzles that have an exit opening for passage of a laser beam onto a workpiece; an annular gap surrounding the exit opening; and a sleeve disposed and guided displaceably within the annular gap for axial displacement between a rearward and a forward position. The sleeve projects beyond the exit opening at least in the forward position, and the sleeve is tiltably mounted in the annular gap.

Provided is a laser welding apparatus that performs welding by irradiating a laser beam onto a welded part, the laser welding apparatus including: a shielding gas supply unit that supplies a shielding gas to the welded part; a gas feed rate controlling unit that controls a flow rate of the shielding gas; a light intensity measurement unit that measures a light intensity of plasma light emitted from the welded part; and a rate-of-change calculation unit that calculates a rate of change of the light intensity measured by the light intensity measurement unit. The gas feed rate controlling unit controls, according to the calculated rate of change of the light intensity, the flow rate of the shielding gas supplied to the welded part.

A method for evaluating a laser cut edge of a workpiece includes capturing image data of the laser cut edge and its surroundings, segmenting the image data, and identifying a segment of interest of the image data. The segment of interest comprises image data of the laser cut edge. The method further includes carrying out an image quality detection for the segment of interest and generating, based on the image quality detection, an output for a user.

A laser processing apparatus includes: a laser-beam irradiation device that forms a processing groove in a workpiece by subjecting workpiece to laser processing while scanning a surface of workpiece; a nozzle that injects a gas W in a range of laser-beam irradiation by laser-beam irradiation device; a motor that changes a position of injection of gas W by nozzle; and a controller. Controller controls motor in accordance with a position of irradiation by laser-beam irradiation device, thereby changing the position of injection of gas W by nozzle.

A metal powder additive manufacturing system and method are disclosed that use increased trace amounts of oxygen to improve physical attributes of an object. The system may include: a processing chamber; a metal powder bed within the processing chamber; a melting element configured to sequentially melt layers of metal powder on the metal powder bed to generate an object; and a control system configured to control a flow of a gas mixture within the processing chamber from a source of inert gas and a source of an oxygen containing material, the gas mixture including the inert gas and oxygen from the oxygen containing material.

A metal powder additive manufacturing system and method are disclosed that use increased trace amounts of oxygen to improve physical attributes of an object. The system may include: a processing chamber; a metal powder bed within the processing chamber; a melting element configured to sequentially melt layers of metal powder on the metal powder bed to generate an object; and a control system configured to control a flow of a gas mixture within the processing chamber from a source of inert gas and a source of an oxygen containing material, the gas mixture including the inert gas and oxygen from the oxygen containing material. The method may result in an object having a surface porosity of no greater than approximately 0.1%, and an effective density of greater than approximately 99.9%.

A laser processing system herein includes a laser oscillator, a laser optical path that guides laser beam from a laser beam emission port of the laser oscillator to a workpiece, an impure gas adsorbent for adsorbing impure gases that influence the propagation of the laser beam, and a shutter that exposes the impure gas adsorbent in the laser optical path.