This disclosure relates to methods and apparatuses for piercing workpieces at a piercing point using a laser beam, which exits from a laser processing nozzle with a process gas, whereby a bulge is formed on the workpiece surface around the piercing point during the piercing. A distance between the laser processing nozzle and the bulge is determined during the piercing and at least one piercing parameter is changed in dependence on the distance determined.

A mechanism for detecting the inside of a workpiece includes a wavelength delaying unit for outputting each pulse of a pulsed laser beam emitted from a laser oscillator with time differences imparted to respective wavelengths, and a ring generating unit for generating a ring-shaped pulsed laser beam from the pulsed laser beam with the time differences imparted to the respective wavelengths and diffracting the ring-shaped pulsed laser beam into ring-shaped laser beams ranging from small to large at the respective wavelengths. When the ring-shaped laser beams with the time differences imparted to the respective wavelengths are applied to the workpiece, they produce an interference wave of ultrasonic waves in the workpiece, and vibrations are produced at a position where the interference wave of the ultrasonic waves is converged. A laser beam is applied to an upper surface of the workpiece at a position aligned with the center of the vibrations.

A system and method for removing a protective shield from an electrical cable using an ablation process is disclosed. The circumference of the protective shield may not be perfectly circular. To compensate, a measurement, such as a distance measurement to a point on a surface of the electrical cable, is performed. Based on the distance measurement, the system performs a compensation operation, such as moving the lens in the laser system in order to compensate. Thereby, the focus of the laser radiation may be placed consistently at a predetermined position relative to the surface of the protective shield, thereby sufficiently ablating the protective shield without harming interior layers of the electrical cable. Further, the protective shield may be wrapped so that there is an overlap. To account for this, the protective shield on both sides of the ablated groove is held and twisted in order to shear along the groove.

A method for measuring the depth of the vapour cavity during an industrial machining process employs a high-energy beam. An optical measuring beam is directed towards the base of a vapour cavity. An optical coherence tomograph generates interference factors or other raw measurement data from reflections of the measurement beam. An evaluation device generates undisturbed measurement data, wherein raw measurement data that is generated at different times is processed together in the course of a mathematical operation. This operation can be a subtraction or a division. Slowly changing interference factors can thus be eliminated. An end value for the distance to the base of the vapour cavity is calculated from the undisturbed measurement data using a filter. As a result, the depth of the vapour cavity can be determined, in the knowledge of the distance at a part of the surface of the work piece that is not exposed to the high-energy beam.

A continuous welding method and device for a hybrid welding, a welded finished product and a train body. The method comprises: performing hybrid welding on a groove of a welding piece by coupling a laser and a variable polarity arc; wherein the defocusing distance of the laser is not less than a Rayleigh length of the laser. According to the method of the present disclosure, the power density of the laser on the surface of the welding piece is effectively reduced and the height-width-ratio of the weld seam is decreased, the diameter of the welding melted pore is increased, the voids caused by the collapse of the small pore in the welding melted pore can be effectively reduced, thereby solving the problem that the weld porosity is difficult to escape in the prior art, and reducing the generation of the pores, effectively improving welding stability and reliability, and improving the mechanical properties of the weld seams.

Apparatus for distance gauging in laser material processing includes a source of laser-radiation, an electrically-conductive focusing assembly, a constant-current source, and a voltmeter. The focusing assembly focuses laser-radiation towards an electrically conductive workpiece being processed. The focusing assembly and the workpiece form a capacitive sensor. The constant current source provides a constant electrical current to the focusing assembly for a constant time. The focusing assembly and the workpiece are separated by a distance that is proportional to a change in voltage measured on the focusing assembly during the constant time.

An SiC substrate processing method for producing an SiC substrate from an SiC ingot. The SiC substrate processing method includes a separation layer forming step of setting a focal point of a laser beam having a transmission wavelength to SiC inside the SiC ingot at a predetermined depth from the upper surface of the SiC ingot and next applying the laser beam LB to the SiC ingot to thereby form a separation layer for separating the SiC substrate from the SiC ingot, a substrate attaching step of attaching a substrate to the upper surface of the SiC ingot, and a separating step of applying an external force to the separation layer to thereby separate the SiC substrate with the substrate from the SiC ingot along the separation layer.

Methods of determining at least one parameter of an irradiation device of an apparatus for additively manufacturing three-dimensional objects may include generating an energy beam and guiding the energy beam across a structured test surface, generating a signal by detecting radiation that is emitted from the test surface, and determining the at least one parameter based on a frequency spectrum of the signal.

A side trimming device according to an embodiment of the present invention may comprise: a cutting unit for mechanically cutting a transferred steel plate; a groove forming unit for forming a groove in a cutting-scheduled area in front of the cutting unit with reference to the steel plate transfer direction; and a washing unit arranged adjacent to the groove forming unit so as to suction molten material accumulating in the groove in the side direction of the steel plate.

A method and system for detecting an operating condition of an optical element along a propagation path of a power laser beam in a laser processing machine head are based on a first signal of a back-propagating optical radiation at the wavelength of the laser beam; a second signal of a back-propagating optical radiation having a wavelength in the near infrared; a third signal of an optical radiation emitted by the optical element in the infrared in proximity to its surface; a fourth signal which is a function of the time-of-flight of an acoustic wave launched through the volume of the optical element.