Aspects described herein relate to additive manufacturing systems and related methods. An additive manufacturing system may include two or more laser energy sources and associated optical fibers. An optics assembly may be constructed and arranged to form a rectangular laser energy pixel associated with each laser energy source. Each pixel may have a substantially uniform power density, and the pixels may be arranged to form a linear array of laser energy pixels on a build surface with no spacing between the pixels. Exposure of a portion of a layer of material on the build surface to the linear array of laser energy pixels may melt the portion of the layer.

A method for machining a tool includes applying compressive residual stress to the tool by laser peening using a pulsed laser. The tool includes a base material and a coating layer that covers at least a portion of a surface of the base material. In the applying, the compressive residual stress is applied to the tool such that a difference in compressive residual stress at an interface between the base material and the coating layer is at most 100 MPa.

A thermal processing apparatus and method in which a first laser source, for example, a CO.sub.2 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 CO.sub.2 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.

A method of laser welding a workpiece stack-up (10) that includes at least two overlapping metal workpieces (12, 14) comprises advancing a laser beam (24) relative to a plane of a top surface (20) of the workpiece stack-up (10) from a start point (84) to an end point (86) along a beam travel pattern (78) at a high laser beam travel speed of greater than 8 meters per minute. The two or more overlapping metal workpieces (12, 14) may be steel workpieces or they may be aluminum workpieces, and at least one of the metal workpieces (12, 14) includes a surface coating (40). Advancing the laser beam (24) along the beam travel pattern (78) forms a weld joint (76), which includes resolidified composite workpiece material derived from each of the metal workpieces (12, 14) penetrated by a molten weld pool (80), that fusion welds the metal workpieces (12, 14) together. The relatively high laser beam travel speed contributes to improve strength properties of the weld joint (76).

A laser processing apparatus includes: a chuck table that holds a workpiece; a laser beam applying unit that applies a pulsed laser beam having a predetermined line width to the workpiece held by the chuck table; and a processing feeding unit that performs relative processing feeding of the chuck table and the laser beam applying unit. The laser beam applying unit includes: a laser oscillator that oscillates the pulsed laser beam; a focusing device that focuses the pulsed laser beam oscillated by the laser oscillator; and a pulse width adjustment unit that is disposed between the laser oscillator and the focusing device and that generates a time difference in a wavelength region of the pulsed laser beam in the predetermined line width, thereby adjusting the pulse width.

The present invention is characterized in that by laser beam being slantly incident to the convex lens, an aberration such as astigmatism or the like is occurred, and the shape of the laser beam is made linear on the irradiation surface or in its neighborhood. Since the present invention has a very simple configuration, the optical adjustment is easier, and the device becomes compact in size. Furthermore, since the beam is slantly incident with respect to the irradiated body, the return beam can be prevented.

An additive manufacturing device includes: an inner light beam radiation device of radiating an inner light beam; an outer light beam radiation device of radiating an outer light beam; and a control device. when a molten pool is irradiated with the outer light beam, the control device controls a power density of the outer light beam representing an output per unit area such that a cooling rate of the molten pool representing a temperature drop per unit time is 540 C./s or less at a freezing point of a carbide binder included in the molten pool, the molten pool being formed by irradiating a material including a hard material and a carbide binder with the inner light beam to melt the material. According to the present disclosure, the additive manufacturing device can prevent cracking and additively manufacture a high-quality shaped object with a simple configuration.

The device comprises a welding unit with a tube (3), a laser radiation unit (1) radiating in direction of the tube axis (3.0), and a mandrel (4) which is connected to the tube (3) via a holding unit which is formed, e.g., by two spacer elements (5.1) and which is coaxially arranged relative to and in the tube (3). The tube (3) and the circumferential surface of the mandrel (4) are reflective of the laser radiation of the laser radiation unit (1) such that through multiple reflections between the tube (3) and the mandrel (4) the laser radiation is deflected toward the beam output-side tube end (3.2) and is shaped annularly.

A profile selector includes at least one beam-forming lens refracting a laser beam to be incident so as to convert a beam profile and emits a laser beam having a beam profile selected from a plurality of beam profiles. A collimating lens converts a laser beam of a divergent beam to be incident into collimated light. A focusing lens focuses the collimated light emitted from the collimating lens and irradiates the focused beam to a sheet metal of a processing target. A moving mechanism moves the collimating lens along an optical axis such that a deviation of a focal point is reduced caused when the beam profile of the focused beam emitted from the focusing lens is selected by the profile selector.

A laser-arc hybrid welding apparatus includes a laser torch and a welding torch. The laser torch includes a DOE. The DOE enlarges a laser irradiated region in a direction of width of welding as compared with irradiation without the DOE and adjusts a shape of the irradiated region to allow a distribution in the width direction, of a quantity of heat input by laser to exhibit a prescribed profile. The prescribed profile refers to such a profile that a central portion in the width direction is not larger in quantity of heat input than an end in the width direction.