A laser shock and supersonic vibration extrusion co-strengthening device and method. The device comprises a laser assembly, a vibration assembly, a hydraulic assembly and a connecting assembly. The method strengthens a hole (7) formed in a metal sheet (5) simultaneously by laser shock strengthening and supersonic vibration extrusion strengthening; a mandrel (1) is in clearance fit with the hole to constrain the hole, so as to avoid distortion of the hole and a hole angle when the laser shock is performed on an outer surface of a workpiece and to improve the strengthening effect of a hole wall; when the laser shock is performed on the outer surface of the metal sheet, supersonic vibration is applied by the mandrel in the hole; and a three-dimensional pressure stress distribution nearby the hole wall at a certain depth is formed under an interaction produced by power ultrasound and laser shock waves having a certain frequency, amplitude and modality, so that an inner surface having higher anti-fatigue performance and being smoother is provided to the hole. Defects of a traditional strengthening process are overcome, and the problem in strengthening the hole separately through the laser shock or supersonic vibration extrusion is solved.

A 3-D printing method and a 3-D printout are provided. In an embodiment, the 3-D printing method includes laser-scanning a printing material according to a 3-D printing model so that the printing material starts to be sintered into a printout in a shape, layer by layer from the bottom up; and feeding a treatment gas into a 3-D printing device and laser-scan a local area of the printout so that the treatment gas reacts with the surface of the local area of the printout and a hardened layer is formed. The laser scanning and the feeding of the treatment gas are performed alternately until a printout with local hardened layers is formed. By adjusting the gas environment, the components can be manufactured by selective laser melting equipment to have a wear- and corrosion-resistant nitrided surface layer and keep the expected ductility of the central area.

A machine component, made of steel or cast iron and having a circular hole that opens in a first surface, includes a plurality of first quench-hardened regions that include the first surface and are arranged apart from each other along a first circle surrounding the hole when viewed in a plane in a direction perpendicular to the first surface, and a base region that is a region other than the first quench-hardened regions.

A method is provided for laser hardening a substantially cylindrical surface of a workpiece, e.g. the wheel rim of the wheel disk of a track-guided railway wheel, at least with a partial width of its wheel tread and/or of the side of its flange facing the wheel tread, which are subjected to abrasion. The method includes projecting a laser spot, by means of a laser source, onto the surface of the wheel disk which is to be processed, producing relative movement between the surface and the laser source by rotating the wheel disk about its axis of rotation, scanning the laser beam with respect to the surface which is to be processed, during the rotational movement, and modulating the laser beam in accordance with various criteria, for example with respect to its power and/or its scanning speed and/or its laser spot size and/or its scanning pattern.

A method is provided for laser hardening a substantially cylindrical surface of a workpiece, e.g. the wheel rim of the wheel disk of a track-guided railway wheel, at least with a partial width of its wheel tread and/or of the side of its flange facing the wheel tread, which are subjected to abrasion. The method includes projecting a laser spot, by means of a laser source, onto the surface of the wheel disk which is to be processed, producing relative movement between the surface and the laser source by rotating the wheel disk about its axis of rotation, scanning the laser beam with respect to the surface which is to be processed, during the rotational movement, and modulating the laser beam in accordance with various criteria, for example with respect to its power and/or its scanning speed and/or its laser spot size and/or its scanning pattern.

Hot rolling stock (1) made of metal which is rolled in at least one roll stand (2) and then cooled in a cooling section (5) arranged downstream of the at least one roll stand (2). Sound generated by means of a sound generator arrangement (8) is coupled into the rolling stock (1) by a coupling device (1) so that a standing sound wave is formed at least in the region of the rolling stock (1) which is located in the vicinity of the coupling device (10).

A method for processing corrosion resistant austenitic stainless steel includes: preparing a workpiece made of austenitic stainless steel; and applying compressive residual stress to a surface layer of the workpiece without subjecting the surface layer to plastic working.

A delivery device that is usable in a laser peening operation emits a columnar flow of a fluid that contains therein a beam of electromagnetic energy. The beam is retained within the interior of the flow of fluid since the total internal reflectivity of the flow is sufficient to do so. The flow of fluid that serves as a conduit for the beam also itself impinges on a workpiece and thus contains and washes away the plasma that forms from a laser peening operation, and this resists the plasma from reaching and possibly damaging the delivery device. The carrying of the beam in the columnar flow of fluid avoids the need to maintain a fixed distance between the delivery device and the workpiece, which simplifies the movement by a robotic manipulator of the delivery device along a non-planar surface of a workpiece during a laser peening operation.

A delivery device that is usable in a laser peening operation emits a columnar flow of a fluid that contains therein a beam of electromagnetic energy. The beam is retained within the interior of the flow of fluid since the total internal reflectivity of the flow is sufficient to do so. The flow of fluid that serves as a conduit for the beam also itself impinges on a workpiece and thus contains and washes away the plasma that forms from a laser peening operation, and this resists the plasma from reaching and possibly damaging the delivery device. The carrying of the beam in the columnar flow of fluid avoids the need to maintain a fixed distance between the delivery device and the workpiece, which simplifies the movement by a robotic manipulator of the delivery device along a non-planar surface of a workpiece during a laser peening operation.

A multi-track laser beam process for surface hardening a low-carbon and low manganese steel. The process includes providing cold rolled close annealed (CRCA) steel sheets having in weight percentage, C: 0.03-0.07, Mn: 0.15-0.25 or 1.4, S: 0.005-0.009, P: 0.009-0.014, Si: 0.005-0.02, Al: 0.04, V: 0.001, Nb: 0.001, and Ti: 0.002 and heating the surface of the steel sheet to an austenizing temperature using a multi-track laser beam, where, upon cooling, phase transformation of the initial microstructure to a harder dual phase structure occurs. The surface temperature of the steel sheet may be controlled based on a comparison of the on-line surface temperature effect with pre-stored data representing the desired surface temperature effect to eliminate any possibility of melting the sheet. The development of the desired microstructure of the sheet, including measurement of the hardness level and the fraction of different phases, may be periodically reviewed.