Abstract: A plasma arc-laser hybrid welding method for a high-sealing aluminum alloy thick plate rectangular chamber is provided. A length, height and width of the rectangular chamber of the high-sealing aluminum alloy thick plate are all ?350 mm. The aluminum alloy tensile plate material for the chamber is AL6061-T6, the plate thickness is 20 mm-25 mm, and the adjacent plates are in accordance with T The welding wire material is 4043, the diameter of the welding wire is ?1.2 mm, the height and width of the welding seam are required to be greater than 5 mm, the welding seam quality meets GB\12469-1990, and the ultimate vacuum degree of the chamber reaches 1 Pa. It greatly improves the material utilization rate and processing efficiency, and reduces the material and cycle cost. Using hybrid welding technology, compared with single laser welding and plasma welding, the welding quality is effectively improved.

Abstract: The present invention provides a device and method for electromagnetic induction heating-assisted laser additive manufacturing of a titanium matrix composite and belongs to the technical field of laser additive manufacturing. The device includes a coaxial-powder feeding laser deposition system and an electromagnetic induction heating synchronous auxiliary system. The coaxial-powder feeding laser deposition system includes a substrate, a deposition sample, a laser head and an infrared thermometer. The electromagnetic induction heating synchronous auxiliary system includes an electromagnetic induction power supply auxiliary unit, a coil, a steering heightening mechanism, a driven shaft and a transverse sliding groove. The coil is connected to an output end of the electromagnetic induction power supply auxiliary unit. The coil and the laser head do synchronous movement to implement small-area real-time preheating and slow cooling on the deposition sample.

Abstract: The present invention provides a device and method for electromagnetic induction heating-assisted laser additive manufacturing of a titanium matrix composite and belongs to the technical field of laser additive manufacturing. The device includes a coaxial-powder feeding laser deposition system and an electromagnetic induction heating synchronous auxiliary system. The coaxial-powder feeding laser deposition system includes a substrate, a deposition sample, a laser head and an infrared thermometer. The electromagnetic induction heating synchronous auxiliary system includes an electromagnetic induction power supply auxiliary unit, a coil, a steering heightening mechanism, a driven shaft and a transverse sliding groove. The coil is connected to an output end of the electromagnetic induction power supply auxiliary unit. The coil and the laser head do synchronous movement to implement small-area real-time preheating and slow cooling on the deposition sample.

Abstract: The present invention provides a device and method for forming a ceramic-reinforced metal matrix composite (MMC) by follow-up ultrasonic-assisted direct laser deposition (DLD), and belongs to the technical field of additive manufacturing (AM). A positioning and clamping device is used to keep an ultrasonic impact gun to follow a coaxial powder feeding nozzle. During the DLD process of the ceramic-reinforced MMC, the cavitation, acoustic flow and mechanical and thermal effects of an ultrasound are used to intervene in a solidification behavior of a molten pool in real time, and a localized strengthening effect of an ultrasonic impact is used to adjust a stress in real time. Compared with a DLD forming method without follow-up ultrasound application, the method of the present invention effectively reduces the voids inside a workpiece, and ensures the consistency of a solidified structure and the evenness of stress distribution.

Abstract: A method and apparatus for directly forming periodic structures on a substrate by laser irradiation comprises directing a linearly polarized laser beam onto a first location of the substrate; irradiating the substrate for a sustained duration using the linearly polarized laser beam for melting the substrate at the first location to induce a surface wave thereon; the melted substrate having a plurality of ridges corresponding to the wavelengths of the surface wave. The linearly polarized laser beam scans the substrate along a first path to propagate the surface wave on the substrate; and thereafter, substrate is cooled down following scanning of the linearly polarized laser for solidifying the plurality of ridges to form a first group of periodic structure on the substrate. Periodic structures formed according to the invention may be optical gratings such as diffraction or reflective gratings.