682results about How to "Small heat affected zone" patented technology

The present invention provides a laser repaired power generator and turbine rotor shaft, on its matrix surface on alloy covering layer which can be mutually merged with matrix surface and is different from matrix completely in components is formed, and on the surface where the matrix and alloy layer are connected a micromolten layer whose thickness is 0.05-0.1 mm is formed, and said alloy covering layer is nickel base, cobalt base or iron base alloy. Said invention also provides a laser repairing method of the described power generator and turbine rotor shaft. It adopts a pre-set laser melt-covering mode, and its technological parameters are: laser power 1200-2000 W, spot diameter 2-6 mm and spot moving speed 2-20 mm/s.

The invention discloses a laser welding method for a thick plate. A gap is reserved on the thick plate or a divided edge with a blunted edge is performed, a laser autogenous welding is adopted at the welding bead part for welding a pass for bottoming, then, the laser wire filling welding is carried out, a welding wire and a laser beam maintain an included angle being 15 degrees to 75 degrees, the welding wire extends into the divided edge gap from the front of the laser beam, when the filling wire welding cannot fully fill the divided edge gap, the laser-GMAW (gas metal arc welding) composite welding is finally carried out, and the welding of the thick plate is completed. The preserved gap value is respectively smaller than or equal to 0.5mm, the width of the performed welding bead used for the wire filling welding is smaller than or equal to 2.5mm, and the width of the performed welding bead used for the composite welding is smaller than or equal to 10mm. The laser welding method has the advantages that the problem of high-efficiency and high-quality welding of the thick plate is solved, so high-quality and efficient thick plate welding joints with small welding deformation and high gap bridging capability are obtained.

The invention relates to a method for machining micro holes in a ceramic matrix composite through femtosecond lasers. According to the method, the silicon carbide ceramic matrix composite sample is placed on a working table and machined layer by layer in a spiral line mode through the femtosecond lasers or machined in a linear scanning mode, wherein the thickness of the sample is smaller than 3 mm; in the micro-machining process, the wave length of femtosecond laser machining ranges from 400 nm-1500 nm, the pulse width ranges from 80 fs to 500 fs, the output power of the lasers is determined according to the requirements of micro-machining and ranges from 20 mW to 20 W, and the repetition frequency of the lasers is determined according to the requirements of micro-machining and ranges from 50 K to 25 MHz; the sample is machined in a layer-by-layer removal mode, wherein the rotation speed of a machining head is 2400 rev/s. In the machining process, the method has the advantages that machining damage is small, and because material around the damage region is still in a cold state after machining, the heat effect is small; machining precision is high, energy of the femtosecond lasers is in Gaussian distribution, absorption and action of the energy in the machining process are limited within the size of which the focus center is quite small, and the machining dimension is expressed from a micro form to a sub-micro form.

The invention discloses a laser-induced oxidation auxiliary micro milling method and a device thereof. According to oxidable characteristics of a material to be machined, a low-power laser device is used for heating the material in the to-be-machined area, auxiliary oxidizing gas is led to serves as an oxidizing agent, instant high temperature generated by the laser is used for enabling the material in the to-be-machined area and the oxidizing agent to have the rapid controllable oxidizing reaction, through adjusting of laser and oxidizing agent parameters, the oxidizing reaction rate, the oxide microstructure and the structure are controlled, an oxidizing layer is formed on the surface of a workpiece to be machined, the micro milling removing mechanism of the material is changed, the cutting load is reduced, a micro milling cutter is used for rapidly removing the oxide layer and the small number of subsurface stratum materials, and the high-precision machined surface is formed; the higher machining efficiency and the better surface integrality are obtained, and the processing controllability is high; the machining method is used for achieving efficient and high-quality machining of high depth-to-width ratio microstructures of titanium alloy, hard alloy and other materials hard to machine.

The invention relates to a laser micro-processing device and method. The laser micro-processing device comprises a rotating table and a container located on the rotating table, a lower ultrasonic vibrating table is installed at the bottom of the container, an upper ultrasonic vibrating table is fixed to the lower ultrasonic vibrating table, a workpiece is placed on the upper ultrasonic vibrating table, a laser source and a lens are arranged above the upper ultrasonic vibrating table, laser beams penetrate through the lens and reach the surface of the workpiece, an ultrasonic horn is arranged on the upper side of the upper ultrasonic vibrating table and sends ultrasonic waves to the surface of the workpiece, an outer container is connected with the container through a liquid inflow pipe and a liquid outflow pipe, and a spraying nozzle on the liquid inflow pipe faces the surface of the workpiece. When the surface of the workpiece in liquid is immersed in laser irradiation, the ultrasonic horn irradiates the surface of the workpiece or the workpiece is made to generate ultrasonic vibration in the vertical direction and the horizontal direction. Laser and the ultrasonic waves ideally act on the first surface of the workpiece at the same time, different processing effects are achieved, the ultrasonic cavitation phenomenon and the water jetting phenomenon can be intensified, the surface of the workpiece can be cleaned again, and heat-affected zones of processing, cracks and deposition of chippings are reduced.

An in-situ laser repairing method for the rotor shaft of electric generator or turbine includes such steps as nondestructive inspection and cleaning, laser smelting for repairing, and mechanical shaping. It features that after the alloy powder is attached to the rotating rotor shaft, the laser beam is used to radiate the rotor shaft and the water is used as cooling medium, the stepless speed regulator is cooperating with the winder of in-situ electric generator set, and when it is mached, the rotor shaft is static and the cutting tool is moving around it.

The invention relates to a welding technique in equipment manufacture industry, which is a welding speciality technique of a welding casing of an MCL-typed horizontal cutting centrifugal compressor, in particular to a welding process of the welding casing of the centrifugal compressor with low-temperature steel 09MnNiDR material at -70 DEG C. The gas protection welding is adopted; the welding wire grade is HS09MnNiDR and the diameter of the welding wire is Phi1.2mm; the polarity of the power supply is reversed DC power. The invention comprises a processing before welding, a welding process and a processing after welding; wherein, the process parameters in the welding process are that the welding current ranges from 150A to 200A, the welding voltage ranges from 24V to 28V, the protection gas is the mixed gas with 80% of Ar and 20% of CO2 according to the volume percentage, the welding speed ranges from 250mm/min to 280mm/min, the dry elongation ranges from 10mm to 15mm, and the gas flux ranges from 20L/min to 25L/min. The welding wire of the gas protection welding of the invention is not required to be dried, the welding wire is automatically fed in the welding process, and a welding rod is not required to be replaced; as the heat of the MAG melting polar gas protection welding is concentrated, the invention has the advantages of narrow thermal effect area, little deformation, beautiful forming, good quality, low cost, fast welding speed, high welding efficiency, etc.

The present invention discloses a laser processing head and a multi-light source, multi-function and multi-axis processing apparatus comprising the same. The laser processing head includes a shell, an optical path system, a locating conical disk-shaped connecting mechanism, a laser range finder, a motor driving mechanism and a dust collection protection cover. The laser processing head has the advantages of a plurality of processing modes, flexibility in laser selection and easiness in replacement. The multi-light source, multi-function and multi-axis processing apparatus includes an apparatus control and operation system platform, a multi-axis linkage numerically-controlled machine tool and the laser processing head; the laser processing head is fixed on a high-precision multi-axis linkage machine tool through a blade handle type positioning cone device; and large-breadth and cross-scale laser fine processing only requires the switching of a laser light source, a laser optical path and the laser processing head, so that at least three kinds of large complex component fine surface processing application can be realized. The multi-light source, multi-function and multi-axis processing apparatus is especially for the aerospace field. The laser processing head and the multi-light source, multi-function and multi-axis processing apparatus comprising the same of the invention have the advantages of low manufacturing cost, wide application range, convenience in mass production and the like.

The invention discloses a method for engraving a character or a graphics on a metal mold. The method comprises the following steps: firstly, placing the metal mold on a three-dimensional work table ofa laser engraving machine, and adjusting the metal mould to a corresponding engraving position; secondly, making a character or a graphics to be engraved and adjusting the parameters of the laser engraving machine; and thirdly, scanning layer by layer to reach a required depth. The method for engraving the character or the graphics on the metal mold can solve the problems of the complex flow of the conventional CNC or EDM and liquid medicine corrosion process, simplify the structure design of the mould without generating mechanical extrusion or stress in the process and has the advantages ofsmall heat-affected region, fine process, no deformation of a workpiece, high processing efficiency, low cost and easy operation without pollution.

The invention discloses a butt-jointing and welding method of plates. The bases of the grooves of two plates which need to be welded are butt-jointed closely and are fixed in the groove through spot welding. A ceramic pad is stuck at the bottom of the butt-jointing place by an aluminum foil. Two parallel and separated thin welding wires are used to treat welding seam by submerged arc-welding. The butt-jointing and welding method effectively shunts the welding current to the two thin welding wires, not only improves the melting efficiency of the welding wire, but also avoids the excessive concentration of the active force of electric arc, not only has high welding efficiency, but also is easier to achieve a balance state to form the welding seam under the support of surface tension and the ceramic pad.

The invention relates to a laser-electric arc composite heat source high-speed welding method of ultrahigh strength steel, belonging to the technical field of high-strength steel welding. The traditional laser-electric arc composite heat source high-speed welding method of the high-strength or ultrahigh strength steel has overhigh welding linear energy due to low welding speed and large energy input so as to cause the deformation of a welding workpiece; in addition, chevilled silk spacing is overlarge, and stabilization action realized by a laser is reduced because the laser is adopted firstly and the electric arc is adopted subsequently so that a welding process is unstable and easy to generate splashing. The invention adopts laser-electric arc composite heat source welding; the welding workpiece is the high-strength steel or the ultrahigh strength steel; an electric arc welding gun is used for welding firstly and a laser nozzle is used for welding subsequently during welding; the current of electric arc welding is 140-180A, and the voltage of the electric arc welding is 23-25V; an included angle theta between the electric arc welding gun and the surface of the workpiece is 60-65 degrees; the laser power is 3-5kW; the welding speed v is 1-3m/minute; and the chevilled silk spacing h between a laser beam and a welding stick is determined within a range of 1-3mm. The invention realizes the welding of the ultrahigh strength steel without preheating, cold cracks or deformation.

The invention relates to an ultraviolet laser drilling device. The output end of an ultraviolet Q-switched solid laser is provided with a beam expander; the output end of the beam expander is sequentially provided with a first reflecting mirror and a second reflecting mirror; the output end of the second reflecting mirror is provided with a beam shaping device; the output end of the beam shaping device is provided with a scanning galvanometer; the output end of the scanning galvanometer is connected with a focus lens; a three-dimension moving platform is arranged below the focus lens; light beams emitted from the ultraviolet Q-switched solid laser enter the beam expander; the beam expander outputs collimated light beams; the collimated light beams enter the beam shaping device through the first reflecting mirror and the second reflecting mirror; the shaped light beams enter the focus lens through the scanning galvanometer; focusing light spots, of which the energy is in a flat top distribution, are obtained at a focus position; the focus of the focused light beams is positioned on a processing workpiece of the three-dimensional moving platform. During the action of ultraviolet laser and materials, molecules are stripped off by breaking chemical bonds of the materials, a heat affected area is greatly reduced, and a good effect of processing edges is achieved.

The invention relates to a laser and electric arc combined welding method for thick high-strength steel plates and a clamp for the method. A 45-mm thick high-strength steel is welded with a 6-KW fiber laser and through a double-sided welding forming method, small double-sided grooves are opened, and a 1mm-1.5mm gap is reserved, accordingly, the 45-mm thick high-strength steel can be completely welded. Compared with traditional multi-layer multi-pass welding which requires at least 20 passes of welding, the combined welding method has the advantages that the progress is apparent, preheating processes are simplified, preheating time is shortened, and welded joint performances reach client required indexes; the production efficiency is improved apparently, consumption of base metal and welding wires is reduced, energy consumption is decreased, the mechanical property of welded joints is improved, the residual stress and the deformation are reduced, automation of production can be easily achieved, and the like. The special clamp is a combined clamp with four pressing plates arranged on the upper portion and a base plate used on the lower portion during welding so as to improve the efficiency and quality of the welding method. By means of the clamp, a workpiece can be positioned and fixed, the welding quality is guaranteed, and the workpiece cannot be abraded.

The invention relates to a device and a method for making metal film group holes by using ultra-short pulse laser. An optical shutter is arranged at the output end of a high-frequency ultra-short pulse laser device, a beam expander is arranged at the output end of the optical shutter, a 45-degree total reflector is arranged at the output end of the beam expander, a vibrating mirror and a scanning field mirror are sequentially arranged at the output end of the 45-degree total reflector, the scanning field mirror is opposite to a working platform, a charge coupled device (CCD) alignment observation system is arranged above the working platform, a group of clamping cylinders are arranged on the working platform, an air blowing system is arranged at one side of the working platform, a dust collecting system is arranged at the other side of the working platform, and a dust collecting system is also arranged below the working platform. By optical focusing of the ultra-short pulse laser device, the focal point is positioned on a metal film material, so that energy of the laser device is efficiently utilized; and by controlling the pulse number and the pulse duration of the ultra-short pulse laser device, the pulse number and the pulse time for forming each metal film aperture are modulated, so that required apertures on each metal film are sequentially machined.

The invention discloses a laser high-frequency alternating-current pulse tungsten inert gas (TIG) hybrid welding process. The process comprises the following steps of: constructing a laser high-frequency alternating-current pulse TIG hybrid welding system, and gathering an TIG arc and a semiconductor laser beam on the same welding position of a welded workpiece 8 in the same welding direction, to form a molten bath, wherein an inclined angle alpha of 10-40 degrees is formed between the TIG arc tungsten electrode tip end and a vertical direction, the semiconductor laser beam forms an included angle beta of 10-30 degrees with the vertical direction, the TIG arc tungsten electrode tip end keeps a vertical distance H of 2-4mm with the surface of the welded workpiece 8, and the TIG arc tungsten electrode tip end and the semiconductor laser beam keep a horizontal distance D of 2-5mm with an action point of the surface of the welded workpiece 8. The process disclosed by the invention can refine weld microstructure, remarkably reduce or eliminate pores in melting area and effectively improve mechanical performance and anti-stress corrosion performance of a high-strength aluminous alloy welding joint, and the process is quite practical.

The invention discloses an iron-based nanocrystalline composite coating for protecting a boiler tail heating surface and a laser-cladding forming process of the iron-based nanocrystalline composite coating. The iron-based nanocrystalline composite coating comprises the following components in percentage by weight: 49.9-62.8% of Fe, 14.2-20.4% of Cr, 9.0-16.3% of Mo, 2.9-4.1% of B, 0.6-1.3% of C, 1.0-2.4% of Mn, 3.4-8.0% of W, 1.0-1.9% of Si and 0-3.9% of RE, wherein RE is a rare earth element. The forming process comprises the following steps: preparing alloy powder of the iron-based nanocrystalline composite coating; treating the surface of the boiler tail heating surface; preparing the iron-based nanocrystalline composite coating through a simultaneous powder feeding method and a laser-cladding method, wherein the laser cladding is performed for multiple times. The formed iron-based nanocrystalline composite coating is 1 mm above in thickness. The iron-based nanocrystalline composite coating can obviously enhance the wear resistance and corrosion resistance of the boiler tail heating surface, and reduce maintenance costs of worn and corroded parts and consumption of raw materials of a power plant.

The invention provides a method for T-shaped magnesium alloy section friction stir welding. The method specifically comprises the following steps: alcohol is used for cleaning oil greasy dirt on alloy sections to be welded before welding; on the two sides of a magnesium alloy rib plate, a pair of auxiliary cushion blocks with a shape which is consistent with the shape of the plate is assembled; two magnesium alloy blocks with same geometric size are installed on the auxiliary cushion blocks of the rib plate as wallboards, and auxiliary cushion blocks are assembled on the two sides of the wallboards; by using a tooling, the auxiliary cushion blocks of the wallboards, three magnesium alloy sections to be welded and the auxiliary cushion blocks of the rib plates are transversely clamped on a welding bench; a main shaft of a friction stir welding machine rotates, is gradually inserted into one butting surface of the wallboards and the rib plate sections, is stopped for a while and horizontally moves to start welding, the welding is ended after the main shaft reaches an end point, and a stirring head is drawn out; parallel welding is conducted to the other butting surface, wherein the center spacing between the two weld seams is the thickness of the rib plate.

The invention discloses a Cr12MoV cold stamping mold laser repair technology using cobalt-based tungsten carbide as fusion covering alloy. The Cr12MoV cold stamping mold laser repair technology comprises the following steps: (1) cleaning defects on the surface of a cold stamping mold, and removing grinding racks, oil stains and microcracks on the surface; (2) using Fe316 alloy powder as a bottoming layer, and carrying out laser bottoming fusion covering; (3) using Co06+WC alloy powder as a covering layer, and after cooling the mold to 300-600 DEG C, carrying out laser fusion covering on the covering layer; and (4) carrying out mechanical machining on the surface of the fusion covering layer. According to the technology, the fusion covering layer with high interface bonding strength and compact structure and without cracks is obtained without preheating, the microhardness of the fusion covering layer reaches 58-62HRC9.8N, particularly the fusion covering layer has good abrasive resistance and can meet the production requirements, and the service life of the cold stamping mold can be prolonged.

The invention belongs to the technical field of 4D printing additive manufacturing, and discloses a 4D printing method of a nickel-titanium-based ternary shape memory alloy. The 4D printing method ischaracterized in that a selective laser melting technology is adopted for printing gas atomized prefabricated NiTiZr ternary alloy powder, and a component obtained through printing has the shape memory function; and the laser energy density is changed by changing the technological parameters adopted in the selective laser melting technology, and therefore the changes of the structure and performance of the printed piece are regulated and controlled. According to the 4D printing method, the ternary component Zr is introduced into an existing nickel-titanium binary alloy, the martensite phase transformation temperature is obviously increased, the selective laser melting technology is adopted for forming, and complex parts uniform in structure and high in density can be obtained while the excellent shape memory performance and mechanical performance are guaranteed.

The invention provides a laser processing method and laser processing equipment. The laser processing method comprises the steps as follows: radiating the laser through an incident surface of a material to be processed, and colleting the light on the initial cutting surface of or close to the material to be processed so as to gasify and/or melt the material to be processed at a light collecting point and/or in an area close to the light collecting point; forming an initial thermal removing area on the initial cutting surface; continuously distributing the initial thermal removing areas on the initial cutting face along a preset path so as to form an initial thermal removing line; irradiating the laser to collect the light on the surface of or close to the material to be processed formed in the thermal removing step so as to gasify and/or melt the material to be processed at the light collecting point and/or the area close to the light collecting point, thereby forming a follow-up thermal removing area; and continuously distributing the follow-up thermal removing areas along the preset path so as to form a follow-up thermal removing line.

The invention discloses a preparation method of a metal protective coating for the inner wall surface of an inner bore part and belongs to the technical field of surface engineering. The metal protective coating is mainly applied to perform protective treatment on the inner wall surface of a mechanical inner bore part. The preparation method comprises the following steps: the inner wall surface of the part is subjected to cleaning, presetting a powder/binder coating, drying, high-frequency induction heating cladding, cooling and the like, and then a high-frequency induction cladding coating is prepared on the inner wall surface. The metal protective coating is not only applicable to parts made of iron, cobalt and nickel, but also applicable to ti-based, aluminium-based, copper-based and other conductive inner bore metal parts. The metal protective coating prepared on the inner wall surface of the part has the following advantages: metallurgical bonding is formed between a matrix and the coating; a heat affected zone is narrow, and thermal damage and deformation are not caused for the matrix; a cladding coating and an interface texture are compact, a crystal grain is fine and small, and defects like holes, slag inclusion and cracks are avoided; different metals or alloy powder can be selected as coating materials for preparing a wearproof, antifriction or anticorrosion coating according to the actual working condition demands of the inner wall of the part.