Abstract: A welding or additive manufacturing power supply includes output circuitry configured to generate a welding waveform, a current sensor for measuring a welding current generated by the output circuitry, a voltage sensor for measuring an output voltage of the welding waveform, and a controller operatively connected to the output circuitry to control the welding waveform, and operatively connected to the current sensor and the voltage sensor to monitor the welding current and the output voltage. A portion of welding waveform includes a controlled change in current from a first level to a second level different from the first level. The controller is configured to determine a circuit inductance from the output voltage and the controlled change in current, and further determine a change in resistance of a consumable electrode in real time based on the circuit inductance.

Abstract: A laser welding head with movable mirrors may be used to perform welding operations, for example, with wobble patterns and/or seam finding/tracking and following. The movable mirrors provide a wobbling movement of one or more beams within a relatively small field of view, for example, defined by a scan angle of 1-2°. The movable mirrors may be galvanometer mirrors that are controllable by a control system including a galvo controller. The laser welding head may also include a diffractive optical element to shape the beam or beams being moved. The control system may also be used to control the fiber laser, for example, in response to the position of the beams relative to the workpiece and/or a sensed condition in the welding head such as a thermal condition proximate one of the mirrors.

Abstract: An apparatus may include a diode-pumped solid-state laser oscillator configured to output a pulsed laser beam, a modulator configured to modify an energy and a temporal profile of the pulsed laser beam, and an amplifier configured to amplify an energy of the pulse laser beam. A modified and amplified beam to laser peen a target part may have an energy of about 5 J to about 10 J, an average power (defined as energy (J)×frequency (Hz)) of from about 25 W to about 200 W, with a flattop beam uniformity of less than about 0.2. The diode-pumped solid-state oscillator may be configured to output a beam having both a single longitudinal mode and a single transverse mode, and to produce and output beams at a frequency of about 20 Hz.

Abstract: Provided is a mask manufacturing method which includes preparing a mask sheet and a frame, stretching the mask sheet, and fixing the stretched mask sheet to the frame, and forming cell openings in the mask sheet fixed to the frame.

Abstract: A thermal processing apparatus and method in which a first laser source, for example, a CO2 emitting at 10.6 ?m is focused onto a silicon wafer as a line beam and a second laser source, for example, a GaAs laser bar emitting at 808 nm is focused onto the wafer as a larger beam surrounding the line beam. The two beams are scanned in synchronism in the direction of the narrow dimension of the line beam to create a narrow heating pulse from the line beam when activated by the larger beam. The energy of GaAs radiation is greater than the silicon bandgap energy and creates free carriers. The energy of the CO2 radiation is less than the silicon bandgap energy so silicon is otherwise transparent to it, but the long wavelength radiation is absorbed by the free carriers.

Abstract: A method of additively manufacturing a three-dimensional object may include allocating irradiation of respective ones of a plurality of sequential layers of construction material between a first region and a second region based at least in part on a first irradiation time and/or a second irradiation time. Irradiation of the first region is allocated to a first scanner and the first irradiation time is indicative of a time required for the first scanner to irradiate the first region with respect to at least one of the plurality of sequential layers of construction material. Irradiation of the second region is allocated to a second scanner and the second irradiation time is indicative of a time required for the second scanner to irradiate the second region with respect to at least one of the plurality of sequential layers of construction material. The first irradiation time and the second irradiation time may be at least approximately the same.

Abstract: This disclosure describes various methods and apparatus for characterizing an additive manufacturing process. A method for characterizing the additive manufacturing process can include generating scans of an energy source across a build plane; measuring an amount of energy radiated from the build plane during each of the scans using an optical sensor; determining an area of the build plane traversed during the scans; determining a thermal energy density for the area of the build plane traversed by the scans based upon the amount of energy radiated and the area of the build plane traversed by the scans; mapping the thermal energy density to one or more location of the build plane; determining that the thermal energy density is characterized by a density outside a range of density values; and thereafter, adjusting subsequent scans of the energy source across or proximate the one or more locations of the build plane.

Abstract: Method for producing an object by means of additive manufacturing, wherein said method comprises the steps of: receiving, in a process chamber, a bath of material, wherein a surface level of said bath of material defines an object working area; solidifying, by a solidifying device, a selective layer-part of said material on said surface level; controlled oxidisation, of waste particles originating from said solidifying of said material, by controlling an oxygen level, such that oxidised waste particles are obtained and ignition of said waste particles is avoided. Apparatus for producing an object by means of additive manufacturing.

Abstract: Device and method for laser welding around a circumference of a workpiece. A fixed, non-movable unitary optical reflector has a pair of optical reflecting surface portions on a first side surface and a second side surface, respectively, arranged at an obtuse angle relative to each other. A workpiece is fixed in an assembly having the reflector. During setup, the vertical distance is adjusted between the reflector and workpiece along an axis that is transverse to a longitudinal axis thereof without any adjustment of the reflecting surfaces. The first and second side surfaces define a curve that is transverse to the longitudinal axis. Once setup has been completed, a laser beam is directed so that it moves along the optical reflector to thereby produce a 360 degree circumferential weld around the workpiece. Another assembly is provided to change the laser beam direction multiple times to irradiate a circumference of a fixed workpiece from a fixed laser source.

Abstract: Provided are a laser cutting device and a laser cutting method. The laser cutting device comprises a beam expanding element provided with a plurality of lens sets, wherein optical axes of the plurality of lens sets are located in the same line and each lens set comprises at least one lens; the beam expanding element is configured to convert an incident beam into a first beam; and a spectroscopic element arranged on a light path of an emitted light of the beam expanding element, and wherein the spectroscopic element is configured to convert the first beam into multiple second beams that are annular and spaced apart from each other.

Abstract: Embodiments of systems and methods in pulsed arc welding. A robotic welding system, having a welding torch with a contact tip, is configured to perform the following method: (a) generate and output a series of a determined number of welding output pulses as a welding wire electrode is fed toward a workpiece; (b) stop generating welding output pulses while allowing the welding wire electrode to continue to be fed toward the workpiece in an attempt to electrically short to the workpiece; (c) attempt to confirm that the welding wire electrode has electrically shorted to the workpiece within a determined error time period; and (d) repeat steps (a) through (c) if electrical shorting of the welding wire electrode has been confirmed within the determined error time period, else, shut down the robotic welding system to avoid damaging the welding torch.

Abstract: The present disclosure generally relates to a system for heating a bulk medium includes two or more electrodes spaced apart from one another and coupled to the bulk medium; and a power control system coupled to the electrodes, the power control system configured to heat the bulk medium by shaping a density of the current along a current path between the electrodes, thereby, producing an effective resistance along the current path in the bulk medium that is greater than the resistance of the bulk medium to a DC current, in which the power control system shapes the density of the current within a depth of the bulk medium by tuning a skin-depth of the current, and in which the power control system shapes the density of the current in a direction across the current path by the power control system by tuning a proximity effect of the current.

Abstract: A laser welding apparatus is equipped with a laser head that emits a laser beam and an airflow forming unit that forms sheet-shaped airflows, in which the airflows formed by the airflow forming unit traverse an optical path of the laser beam emitted from the laser head, the airflows traversing the optical path at multiple positions which are spaced from each other in a direction along the optical path in a same direction. The airflow forming unit has an opening between the airflows at the multiple positions, the opening penetrating in a direction in which the airflows traverse the optical path.

Abstract: EDM assemblies mount on a machining surface and discharge rotating sub-electrodes against the surface. The sub-electrodes can also revolve about another shared axis while discharging. Rotation and revolution may be achieved with planetary gears fixed with the sub-electrodes and meshing with a stationary sun gear. Several sub-electrodes can be used in a single assembly. Downward movement of the sub-electrodes from a central shaft on the mount allows several inches of the surface to be machined. Assemblies are usable in a nuclear reactor during a maintenance period to machine a hole for a replacement manway cover underwater in the flooded reactor. The differing rotational movements and vertical movement can be independently controlled with separate motors in the assembly. Power and controls may be provided remotely through an underwater connection.

Abstract: Laser processing head (20) of the present disclosure includes housing (30), transparent protector (40), and temperature sensor (70). Housing (30) includes an optical path of processing laser light (LB). Transparent protector (40) is detachably fixed to housing (30), passes processing laser light (LB), and suppresses dust of work material (W) entering into housing (30). Here, the dust is generated from the work material (W) irradiated with processing laser light (LB). Temperature sensor (70) detects the temperature of transparent protector (40).

Abstract: A high-speed reciprocating wire cutting process in which a wire electrode is transported and precisely guided across a machining area by means of a wire traveling circuit, whereas the cutting process is conducted by repeatedly: (a) running the wire electrode in a first direction until a first reciprocation position, (b) stopping and inverting the traveling direction of the wire electrode, (c) running the wire electrode in a second direction until a second reciprocation position, and (d) stopping and inverting the traveling direction of the wire electrode.

Abstract: A gas metal arc welding system for a robotic arm includes a j-arm, a power block, and a bolt. The j-arm has a first end and a second end each having a through hole. The power block has a first opening defining a first passageway along a longitudinal axis and a second opening defining a second passageway substantially along an axis perpendicular to the longitudinal axis. The bolt has a threaded portion configured to extend through the first opening of the j-arm and into the second passageway of the power block, wherein the bolt retains the j-arm to the power block. The threaded portion of the bolt comprises an internal passageway that extends through a longitudinal axis of the bolt, wherein the internal passageway of the bolt and the first and second passageways of the power block are in fluid communication with each other.

Abstract: An example contact tip for a welding torch includes: a first body section having a first diameter and exterior threads, the first body section having channels extending longitudinally along an exterior surface of the first body section to permit gas flow from a first end of the contact tip to a second end of the contact tip through the channels; a first bore portion having a first inner diameter; and a second bore portion having a second inner diameter configured to contact an electrode wire traveling through the second bore portion, the first inner diameter being larger than the second inner diameter.

Abstract: The present application provides a double-beam laser polishing device and a double-beam laser polishing method for an aluminum alloy, which includes a frame; a rotary workbench and an optical path system, which are arranged on the frame. The optical path system includes: a first fiber laser, a second fiber laser, a first three-dimensional galvanometer, and a second three-dimensional galvanometer. The first three-dimensional galvanometer is connected with the first fiber laser through an optical fiber, and the second three-dimensional galvanometer is connected with the second fiber laser through an optical fiber. The first three-dimensional galvanometer and the second three-dimensional galvanometer are arranged side by side above the rotary workbench in a horizontal direction.

Abstract: The object of the present invention is to make it possible to maintain a stable electric discharge and to achieve a stable quality and machining performance even when a work having a non-uniform composition is machined. A wire electric discharge machining device performs electric discharge machining on a work while controlling an inter-electrode distance between a wire and the work based on an inter-electrode voltage between the wire and the work so as to match a set target voltage. The wire electric discharge machining device includes an inter-electrode voltage measuring unit that measures the inter-electrode voltage, an actual amplitude calculating unit that calculates an amplitude of the measured inter-electrode voltage, and a target voltage correcting unit that corrects the target voltage in such a way that the calculated amplitude approaches the target amplitude that is set to a value larger than zero.