594 results about "Fusion welding" patented technology

The invention belongs to the technical field of fusion welding, and particularly relates to a method for planning multi-layer and multi-welding-seam welding parameters according to welding seam feature information, which comprises the following steps: 1) laser emitted by a 3D visual sensor is perpendicular to a welding seam and scans along the direction of the welding seam, and the 3D visual sensor scans welding seam data and transmits the data to a robot controller in real time; (2) the robot controller processes the weld joint data, the whole weld joint is subjected to multi-layer and multi-pass planning calculation, and the number of welding layers and the number of welding passes of each layer are planned; (3) the robot controller calculates the layer number and the channel number of a welding channel needing to be welded currently, a welding gun track coordinate set on a welding path and welding parameters corresponding to welding path points; and (4) the robot controller adjusts the welding track and the welding parameters in real time according to the step (1) to the step (3) in the current welding bead welding process, so that the purpose of multi-layer and multi-pass planning self-adaptive welding of the medium-thickness plate is achieved.

The invention provides a multi-sensor fusion welding temperature monitoring method and a related device, and the method comprises the steps: dividing a welding region into a plurality of sub-regions according to the spatial distribution of the welding region, and obtaining the initial temperature data corresponding to each sub-region according to various temperature sensors; performing time alignment on the initial temperature data through difference resampling of different sampling points to generate a time sequence temperature matrix; performing real-time quality detection on the time sequence temperature matrix to generate a real-time quality score, and performing weighted combination on the real-time quality score and a preset confidence coefficient parameter table to obtain a dynamic confidence coefficient result set; fusing the effective temperature data exceeding a preset confidence threshold in the dynamic confidence result set according to a fusion rule corresponding to each sub-region to obtain a fused temperature result; and the fusion temperature results of the sub-regions are subjected to time sequence splicing to obtain a global temperature curve of the welding process, so that the accuracy of temperature detection in the welding process can be effectively improved.

The invention relates to the technical field of nuclear fusion devices, and discloses a fusion device cooling pipe welding method and welding device.The fusion device cooling pipe welding method comprises the following steps that two cooling pipes to be welded are prepared; an adapter is welded to the welding face of one cooling pipe, and the nickel content of the adapter is higher than that of the cooling pipe; the radial interior of the adapter and the to-be-welded face of the adapter are polished; the two cooling pipes are assembled, so that the welding face of the other cooling pipe is in butt joint with the to-be-welded face of the adapter; and carrying out self-fusion welding on the adapter and the other cooling pipe. According to the welding method for the cooling pipe of the fusion device, the problem that the magnetic conductivity of the cooling pipe exceeds the standard is solved, and meanwhile the welding quality and the welding qualification rate of the cooling pipe are improved.

The invention relates to the technical field of angle valve manufacturing, in particular to angle valve welding equipment and a working method thereof. According to the equipment, through cooperative operation of the integrated assembling device, the welding device, the gas testing device and the transferring device, automatic assembling, rotary type all-round welding, multi-station circulating detection and closed-loop material circulation of the valve body piece and the connector piece are achieved; wherein the assembling device ensures that a connector piece precisely slides to a valve body piece connecting hole by utilizing the height difference design of a transition groove and a first guide groove, and the welding device rotates relative to a welding gun through a rotating seat to complete the full-circumference fusion welding of a seam between the valve body piece and the connector piece. The gas testing device drives the fixing assembly to circularly flow through the cooling station, the testing station and the discharging station through the rotating disc to achieve seamless connection of detection procedures, and the transferring device executes transverse and longitudinal composite motion to guarantee efficient transferring of materials among the procedures. The whole set of system forms a continuous production line, and the assembly precision, the welding sealing performance and the airtightness detection efficiency of welded finished products are remarkably improved.

The invention discloses a temperature sensing element for an aviation temperature sensor and a packaging method, and belongs to the technical field of aero-engine temperature detection.The temperature sensing element for the aviation temperature sensor comprises a shell, a cavity is formed in the shell in the axial direction, a step face is formed at one end of the cavity, and a plurality of shell through holes are formed in the step face; the platinum resistor unit comprises a ceramic column, a platinum wire wound on the periphery of the ceramic column and a leading-out wire welded with the platinum wire, the ceramic column is provided with an even number of through holes in the axial direction, and the leading-out wire penetrates through the through holes and then extends out of the cavity; the insulating tube is sleeved outside the outgoing line and is matched with the through hole of the shell; the end cover is arranged at the end where the step surface C of the shell is located and is in fusion welding sealing with the end surface of the shell; and the sheath is coaxially fixed at one end, opposite to the end cover, of the shell. The temperature sensing element can solve the technical problems of insulation degradation between the outgoing line and the shell of the existing temperature sensing element and lead series fatigue fracture failure.

The invention discloses a laser-assisted helium arc penetration fusion welding method, and belongs to the technical field of welding. The problems that according to an existing paraxial laser-electric arc composite structure, the welding track is difficult to control, the energy coupling efficiency is low due to laser energy loss, and weld joint partial melting and undercut defects are caused due to uneven distribution of a welding temperature field due to a generated asymmetric heat source are solved. The welding method comprises the steps of 1, pretreatment; 2, after being focused by a focus lens, the laser is divided into three laser beams through a spectroscope, then the three laser beams are converged again through a plurality of reflectors, three fan-shaped light spots are formed on the surface of the to-be-welded plate after convergence, and finally the focal plane position of the laser is adjusted to be located on the surface of the to-be-welded plate; 3, setting welding current and arc voltage; and fourthly, laser is used for assisting helium arc penetration fusion welding. The method is used for laser-assisted helium arc penetration fusion welding.

The invention discloses a multi-gear adjusting rotary switch, which comprises a base, a shell cover, a rotary handle and a contact assembly, and is characterized in that the rotary handle is rotationally arranged between the base and the shell cover and is provided with a driving rod extending along the radial direction of the rotary handle; the contact assembly comprises a plurality of moving contact bridges which are annularly arranged in the mounting cavity with the axis of the rotating handle as the center and are of elastic structures, and a plurality of static contact pieces which are arranged on the base and are opposite to the plurality of moving contact bridges, and the plurality of moving contact bridges are connected and are located on the moving path of the driving rod. According to the technical scheme, the driving rod drives the multiple movable contact bridges to make contact with the multiple static contact pieces in the process of rotating along with the rotating handle, operation pressure is remarkably dispersed through an in-turn contact mechanism formed by the driving rod and the multiple movable contact bridges, continuous stress of a single movable contact bridge is avoided, the mechanical load and the fatigue degree of the movable contact bridges are greatly reduced, and the service life of the movable contact bridges is prolonged. The heating probability is reduced, abrasion and fusion welding risks are reduced, and the mechanical service life is prolonged.

The invention discloses a natural gas pipeline fusion welding seam crack nondestructive testing device, and relates to the technical field of welding seam crack detection. The device comprises a supporting frame, the interior of the supporting frame is semicircular, and an arc-shaped frame is fixedly connected to the interior of the supporting frame. According to the device, the stabilizing assembly and the detection assembly are arranged, the stabilizing assembly is shifted firstly, so that the supporting frame can be stabilized on the natural gas pipeline, the situation that the device deviates from the weld joint due to looseness in the detection process is reduced, then the detection assembly in the arc-shaped frame is started to operate, and an ultrasonic probe is driven to circularly detect the weld joint; through the operation, full-automatic detection of the weld joint of the natural gas pipeline is realized, a worker does not need to hold an ultrasonic instrument by hand to manually rotate along the weld joint of the pipeline, the detection efficiency is greatly improved, and the subjectivity and accuracy of a detection result are effectively improved; and the detection process is more convenient.

The invention belongs to the technical field of fusion welding, and particularly relates to a method for adaptively correcting the track of a welding robot and adjusting welding parameters, which comprises the following steps of: scanning a welding seam through a sensor to obtain a current welding seam section image; the robot controller processes the weld joint section image to obtain coordinates of a middle point of a bottom-layer gap of a weld joint butt joint position; in the welding process of the welding robot, the stored welding track coordinates are repeatedly matched, the track coordinate closest to the current position of the welding robot is found, and the coordinate is judged to be the actual position of a welding seam; the welding robot obtains X-axis offset, Y-axis offset and Z-axis offset according to the current coordinates of the movement position of the robot and the matched welding track coordinates, and the movement track of the robot is corrected through the DPM dynamic path correction technology; and the welding parameters of the welding robot in the swing welding process or the welding process are modified or adjusted in real time.

The invention relates to the technical field of laser welding, and provides a high-speed laser welding wire box process based on multi-beam synergy, which comprises the following steps: step 1, at least three laser beams are adopted as a synergy composite heat source, a main laser beam is responsible for penetration fusion welding, and an auxiliary laser beam is responsible for preheating, post-heating or molten pool stabilization; when the copper-aluminum dissimilar material is welded, an auxiliary laser beam is switched into a green laser; and 2, assembling a multi-beam optical regulation and control unit comprising a diffractive optical element, a quartz field lens and a galvanometer scanning module, splitting a main beam into one main beam and two auxiliary beams through the diffractive optical element, controlling focal depth fluctuation by the quartz field lens, and realizing accurate movement positioning of a laser beam by the galvanometer scanning module. Through integration of multi-beam collaborative design and an intelligent control unit, remarkable breakthroughs are achieved in the aspects of welding efficiency, quality consistency and process adaptability, firstly, in the aspect of efficiency and process, the welding speed is greatly increased, multi-station synchronous operation of an automatic welding unit is matched, and the welding period of a single-line box is remarkably shortened.

The invention belongs to the technical field of non-woven materials and membrane separation, and particularly relates to a separation membrane supporting body with an interlocking structure and a preparation method thereof.The method comprises the steps that firstly, low-crystallinity and sulfonation-modified superfine polyester fibers are introduced into compact layer slurry, and framework polyester fibers and polyester heat bonding fibers are introduced into framework layer slurry; then forming a double-layer wet net by utilizing a double-flow-channel wet-process net forming device, applying gradient increasing negative pressure on one side of the skeleton layer, and enabling the superfine fibers to migrate from the compact layer to pores of the skeleton layer in a controlled manner by virtue of a viscous dragging effect of directional high-speed water flow on the superfine fibers, so as to form a gradient transition interlocking interface layer; finally, plastic deformation of the low-crystallinity fibers and fusion welding of the bonding fibers are utilized, an interlayer structure is locked through segmented hot pressing of a rough pressing section and a fine pressing section, and then cooling shaping is conducted. The prepared separation membrane support has the advantages of excellent interlayer peel strength, ultralow surface roughness, high air permeability, wide adaptability and high safety of the preparation process.

The invention discloses a method for determining the offset distance of a welding gun of a metal plate welding case lock bottom welding seam and a welding method, and belongs to the technical field of fusion welding technologies. The method for determining the offset distance of the welding gun comprises the steps that the machining side welding thickness L1, the metal plate side welding thickness L2 and the bottom locking thickness L3 of the metal plate welding case are obtained, and the axis offset P of a welding gun tungsten electrode and the center of a welding connector is calculated; based on the axis offset P, the opposite position of a welding gun tungsten electrode is determined, the offset angle theta over a welding bead and the diameter phi A of the welding bead are obtained, and the offset distance L between the opposite position of the welding gun tungsten electrode and the position over the welding bead is calculated; and based on the axis offset P of the welding gun tungsten electrode and the center of the welding joint and the offset distance L between the position right opposite to the welding gun tungsten electrode and the position right above the welding bead, the alignment position line of the tip end of the welding gun tungsten electrode is determined at the workpiece welding joint. The welding method comprises the steps that the position of the circumferential automatic welding gun mechanism is adjusted based on the alignment position line, and a welding gun is located in the welding bead upslope direction in the circumferential direction.

The invention discloses a construction method for prefabricating a concrete steel shell combined section in a factory, and relates to the technical field of bridge construction, and the construction method comprises the following steps: S1, manufacturing a wallboard unit; s2, the inner wall plate units are positioned, then the outer wall plate units are positioned, and then welding is conducted to manufacture steel shell segments; s3, annular structure concrete between the inner wall plate unit and the outer wall plate unit is poured, and steel shell concrete segments are formed; s4, secondary machining is conducted on the steel shell concrete segments; s5, vertical position continuous matching pre-assembly is carried out, after pre-assembly is completed, matching parts are installed, and marker lines are marked; s6, bridge site hoisting and positioning are conducted on the steel shell concrete sections; s7, outer wall plates of the steel shell concrete sections are subjected to butt-joint penetration welding, and then inner wall plates are welded; and S8, concrete pouring is conducted on bridge site ring openings of the steel shell concrete sections, and machining is completed. The technical problem that the construction period is prolonged due to prefabrication of the steel shell sections of the steel shell concrete tower in the prior art is solved.

The invention provides an automatic production line for collaborative operation of continuous vacuum laser deep penetration welding and workpiece surface oxidation pretreatment, and relates to the technical field of laser welding, the automatic production line comprises a grinding box, a laser processing box is arranged on one side of the grinding box, and inlets and outlets are formed in the two sides of the grinding box and the two sides of the laser processing box; a connecting channel is fixed to an inlet and outlet between the grinding box and the laser processing box, a sending-out channel is fixed to an inlet and outlet in the outer side of the laser processing box, and compared with the prior art, the grinding box communicates with the laser processing box through the connecting channel, and an extending-out plate and a containing plate for clamping plates are arranged in the connecting channel and the sending-out channel; the clamping distance suitable for plates can be adjusted through the conveying assembly, the plates are driven to be intermittently fed into the grinding box and the laser machining box in a clamping traction mode, air in the laser machining box is pumped out in cooperation with the air storage cylinder, the relative vacuum environment is kept, the effect of laser deep penetration welding is prevented from being affected, assembly line machining is achieved, and efficiency is higher.

The utility model relates to an optical fiber welding protection tube. The optical fiber welding protection tube comprises a heat shrink tube, a hot melting tube and a supporting tube, the periphery of the supporting tube is sleeved with the hot melting tube, the periphery of the hot melting tube is sleeved with the heat shrink tube, and a plurality of liquid injection through holes are formed in the supporting tube. Compared with an optical fiber fusion welding protection tube in the prior art, the supporting tube in the optical fiber fusion welding protection tube is like a protection cage, an exclusive space is provided for the optical fiber, only flowing liquid substances are allowed to enter the exclusive space, the protection cage can protect damage from any direction in 360 degrees of the circumference, and the optical fiber fusion welding protection tube has the advantages of being simple in structure and convenient to use. And more reliable and more symmetrical supporting and protecting performance is achieved. Meanwhile, when the heat shrink tube is heated and shrunk, the heat shrink tube only wraps the outer side of the supporting tube, pressure cannot be directly conducted to the optical fiber, and the optical fiber is prevented from being bent and fractured. Compared with the scheme of a thinner supporting rod and a flat sheet in the prior art, the distributed supporting tubes are used for protecting the optical fiber on the periphery of the optical fiber, and the size after welding is smaller.

The invention discloses a copper-chromium contact with high fusion welding resistance and a preparation method thereof, and belongs to the technical field of contact materials. The preparation method comprises the steps that high-purity electrolytic chromium powder and electrolytic copper powder serve as raw materials, after acoustic resonance powder mixing is conducted, powder upsetting and cold isostatic pressing are conducted in sequence, and a green body is obtained; carrying out gradient sintering and finish machining treatment on the green body to obtain a copper-chromium electrode bar; the copper-chromium electrode bar is subjected to atomization powder making, and copper-chromium alloy powder is obtained; after the copper-chromium alloy powder is sequentially subjected to sheathing, heat treatment, seal welding and hot isostatic pressing sintering, a sheath is removed, and a prefabricated body is obtained; and after the prefabricated body is processed, the surface is remelted by green laser, and the copper-chromium contact with high welding resistance is prepared. According to the method, by improving the purity of the copper-chromium contact and optimizing the morphology and distribution of the chromium particles, the prepared contact is high in purity, the chromium particles are fine and uniform in distribution, the welding resistance and the breaking performance are excellent, and the method is suitable for a high-voltage-grade arc extinguish chamber.

The utility model provides a battery packaging structure and a battery, the battery packaging structure comprises a shell and a cover plate, the contact surface between the shell and the cover plate is an inclined surface, and the inclined surface and the shell form a certain inclination angle, so that during laser welding, the laser welding angle and the shell also form a certain inclination angle, the incident path of a laser beam and the shell form a certain inclination angle, and the laser welding efficiency is improved. Therefore, the incident path and the reflection path of the laser beam are not perpendicular to the shell any more, reflection of the laser beam is greatly reduced, meanwhile, the reflected laser beam cannot be reflected along the incident path, the laser lens cannot be damaged, and the service life of the laser lens is prolonged. The shell and the cover plate are fixed by welding and form the fusion welding structure, and the fusion welding structure extends along the inclined direction of the contact surface, so that the fusion welding structure at least partially covers the contact surface, the stable welding of the shell and the cover plate is ensured, and the structural stability and rigidity of the battery packaging structure are improved.

The invention provides a friction solid-phase additive manufacturing method for improving the bonding strength of dissimilar alloys through interlayer interface texturing. The method comprises the following steps that an aluminum alloy or magnesium alloy plate serves as a base body; depositing a first metal layer on the polished to-be-added area by adopting a friction solid-phase additive process; processing a preset micron-sized three-dimensional texture on the surface of the first metal layer by adopting a laser scanning system so as to form a textured interface, and meanwhile, removing new oxides on the surface of the first metal layer; on the textured interface, a second metal layer which is made of a material different from that of the first metal layer is deposited again through the friction solid-phase additive process, so that a bonding interface which is characterized by micromechanical interlocking is formed between the first metal layer and the second metal layer; layer-by-layer additive manufacturing of a stacked dissimilar alloy having a plurality of dissimilar metal bonding interfaces. According to the method, the interlayer bonding mode of the dissimilar alloy is changed, and the problems of layering and cracking of dissimilar alloy fusion welding additive manufacturing components are effectively solved.

The invention discloses a platinum-iridium series electric contact material, and belongs to the technical field of platinum-iridium series electric contact materials. According to the platinum-iridium alloy, alloy elements of Nb, Ru and Re are added into the platinum-iridium alloy, expensive precious metal raw materials of Pt and Ir can be saved, a platinum-iridium alloy ingot blank is prepared through the high-flux electric arc melting technology, and then the platinum-iridium alloy ingot blank is subjected to the machining processes of rolling, drawing, heat treatment and the like to finally form finished products of sheets, wires and the like. The prepared platinum-iridium electric contact material has the characteristics of high melting point, high density, high hardness, wear resistance, high resistivity, stable contact resistance, fusion welding resistance, arc ablation resistance and the like, and can be applied to materials of components such as igniters, spark plugs, relay contacts, transmitting tube filaments and the like.

The invention discloses an ultrasonic-annular water cooling synergetic thermosetting composite material repairing method and equipment, on the basis of coaxial annular water cooling, an annular cooling cavity with a variable contour and a structural design of a closed ring with a plane contour which can be circular, elliptical, waist-circular or polygonal are introduced, so that the inner side contour of a cooling ring can be more attached to a welding area. For a large-size or irregularly-shaped thermosetting matrix component repaired by adopting ultrasonic local fusion welding, the cooling zone can be tightly attached to the outline of a welding interface in the circumferential direction through the design, heat is effectively prevented from overflowing along a complex boundary, compared with a fixed circular or linear cooling structure, the range of a heat affected zone can be further narrowed, and the service life of the component is prolonged. And a high-temperature area in the thermosetting matrix is more limited near a welding interface, so that the overall temperature of the thermosetting matrix is always lower than the glass-transition temperature while sufficient melting and flowing of the thermoplastic patch are ensured, and resin degradation and interface strength attenuation caused by local overheating are avoided.

Provided is a panel type radiator with reinforcing ribs and cooling fins in lintel welding, which includes multiple cooling fins, two oil collecting tubes, multiple reinforcing ribs and multiple welding seams. Each cooling fin is formed by welding two cooling sub-fins oppositely arranged. An edge of a long side of the cooling fin intersects with an outer surface of the reinforcing rib, and a gap suitable for a lintel-shaped weld is provided at an intersection. A welding material droplet weld is formed between an outer edge at an attached position of the long side of the cooling fin and the outer surface of the reinforcing rib, and the shape of the weld is lintel-shaped. The lintel-shaped weld is divided into three regions. The welding material fusion welding connection lintel region is self-fusion welding metal of the welding material.

A method and apparatus for cooperatively preparing a multi-level heterostructure of a weld seam by using dual laser beams. Said preparation apparatus comprises an optical fiber laser (1) provided with a galvanometer system, a short-wave laser (2), a dual-band hybrid wobble welding head (4), an optical path system (3), a robot control system (5), a cooling system (6), and a protection apparatus (7). Said method comprises: using an optical fiber laser (1) to perform wobble filling welding, using an Al-Si-Mg-Cu-Zn-Sn-based alloy as a filling material for a weld seam, and obtaining a weld seam having a heterogeneous crystalline structure; at the same time, using a short-wave laser for on-line baking the weld seam, which promotes complex precipitation of various nano-phases and a gradient distribution in the depth direction of the weld seam. According to said apparatus and method, a weld seam made of an aluminum alloy provided with a combination of multi-level heterostructures can be prepared, the comprehensive performance of the weld joint is cooperatively improved, and thus the problem of unmatched strength and plasticity of a fusion weld seam of a heat-treatable reinforced aluminum alloy is solved.

The invention belongs to the technical field of laser welding, and discloses a thin plate laser lap joint welding method and laser welding equipment. The power of the laser acting on the surface of the upper plate and the power of the laser acting on the lower plate are both smaller than the power of the laser acting on the center of the weld joint, that is, the laser power is in a low-high-low change trend in the direction from the upper plate to the center of the weld joint to the lower plate, and it is ensured that the laser in the center of the weld joint can penetrate through the upper plate; laser on the two sides of the center of the welding seam is controlled in the state that the laser cannot penetrate through the plate, so that energy input in different subareas of the welding seam is accurately controlled, it is guaranteed that the penetration depths of all the subareas are controllable and different, the problems that the penetration depths are unstable, the contour of a molten pool is discontinuous, and a lower plate is prone to penetrating are solved, the welding seam is good in consistency and free of inward concave or outward convex, and continuous smooth transition is achieved; the size measurement of the molten pool meets the standard requirements, the welding quality and the welding efficiency are effectively improved, welding wires are not needed, and the cost is effectively reduced.

The invention belongs to the technical field of dissimilar metal welding, and particularly relates to a laser welding-brazing method for titanium steel dissimilar metal connection. According to the laser welding-brazing method, the laser is adopted as a welding heat source, and laser welding combining brazing and fusion welding is achieved by comprehensively regulating and controlling the filling material, the laser beam position and welding parameters. By the adoption of the welding mode, metallurgical regulation and control of welding seams can be effectively achieved, generation of brittle intermetallic compounds is restrained, a high-quality welding joint with excellent strength and plasticity is obtained, the tensile strength of the welded joint is 317.6 MPa and reaches 82.71% of that of steel base metal and 75.44% of that of titanium base metal, the joint coefficient is 0.83, equal-strength matching is basically achieved, and the welding quality is improved. The welding problem of the titanium steel dissimilar metal is effectively solved, technical support can be provided for matched use of titanium alloy and traditional steel and iron materials, and development of the transportation tool lightweight technology is further promoted.

The invention discloses a high-strength weldable aluminum alloy cold pressure welding connection and heat treatment method. The method comprises the steps of material preparation, cold pressure welding connection, subsequent heat treatment and the like. According to the method, room-temperature cold-pressing butt welding and overall heat treatment are combined and applied to the 7000-series high-strength weldable aluminum alloy, heat input and component deformation in the connection stage are reduced, the welding coefficient of a connection joint can reach 89%-99%, and the method is remarkably superior to fusion welding and other solid-phase welding methods. And a melting solidification structure is not formed in the joint area, so that the structure state and the mechanical performance of the joint area are closer to those of the base material area through a subsequent process, and good overall consistency can be kept under the scenes of long material splicing, component extension and the like. Meanwhile, the process route has certain combination flexibility, and compared with the process only depending on single fusion welding or friction stir welding, the multiple cold pressure welding and heat treatment combination routes are provided to adapt to wires and bars of different specifications and different production rhythms.

The invention belongs to the technical field of welding, and particularly discloses a solid welding wire fusion repair welding method which comprises the steps that a to-be-fusion repair area is cleaned; the extending length of a tungsten needle on the argon tungsten-arc welding gun is adjusted not to exceed the inner diameter of a nozzle of the argon tungsten-arc welding gun; the height from the tungsten needle to the to-be-repaired area is adjusted to be a preset height, so that the electric arc does not deviate; the fusion repair included angle is adjusted to be within a first preset angle on the two sides of the weld toe included angle bisector; welding toes and plates around the welding toes are molten again through an electric arc, molten metal on the two sides of the welding toes is drained to the middle area through the surface tension of a molten pool after melting, and the surface of the solid welding wire welding seam is made to be smooth. By means of the method, a smooth transition area can be formed on the surface of the weld toe, the effect of stress concentration of the weld toe can be remarkably reduced, the weld bead shape can be finished by replacing a grinding machine with the method of weld toe fusion repair between layers, the incomplete fusion condition is reduced, and therefore the internal quality of the weld is improved.

The invention discloses a bimetallic sliding bearing and an additive preparation method thereof. The preparation method comprises the following steps: surfacing a welding wire A and a welding wire B on the surface of a steel substrate in a double-wire welding alternate arcing manner; during alternate arcing, the welding wire A is melted firstly, then the welding wire B is melted, the welding wire A and the welding wire B are arranged in an inclined and crossed mode, and the center lines of the two welding wires are focused on the same point of the surface of the steel base body; the welding wire A comprises any one of a pure tin wire, a tin-nickel alloy wire and a nickel-tin plated welding wire; and the welding wire B comprises a pure copper wire or a copper alloy wire. Two molten pools are mixed by controlling double-wire components, wire feeding angles and welding parameters, so that in-situ synthesis of high-tin bronze is realized, and the problem that the high-tin bronze welding wire is difficult to prepare is solved; an iron-tin phase formed by the tin-melting welding wire firstly can effectively prevent liquid copper from permeating into a carbon steel substrate, and permeation cracks can be reduced or avoided; and a variable polarity technology is introduced, so that the heat input of a matrix is greatly reduced, the propagation of permeation cracks is inhibited, and the bonding strength of heterogeneous additive materials is improved.

The invention belongs to the field of repair of high-temperature alloy hot-end components, and particularly relates to a high-strength fusion welding repair method for a difficult-to-weld gas turbine hot-end component. The method comprises the following steps: (1) removing defects of the hot end component of the gas turbine; (2) degreasing the repairing area; (3) carrying out fusion welding repair on the defects by adopting a body welding wire; (4) a surfacing sheath is prepared on the outer surface of the repaired area through solution-strengthened nickel-based alloy welding filler; (5) carrying out hot isostatic pressing treatment on the hot end component; (6) machining and coping a repair area of the hot end component; (7) carrying out nondestructive flaw detection on a hot end component repair area; (8) carrying out standard heat treatment on the hot-end component; and (9) carrying out nondestructive inspection on the hot-end component. The method is used for fusion welding repair of casting defects of the high-temperature alloy hot-end component with high Al + Ti content and difficult to weld and service damage generated after service of the blade, and crack-free high-strength fusion welding repair of the gas turbine hot-end component with poor weldability can be achieved.

The invention belongs to the technical field of laser welding, and discloses a thin plate laser lap joint welding method, a laser device and laser welding equipment. The power of the laser acting on the surface of the upper plate and the power of the laser acting on the lower plate are both smaller than the power of the laser acting on the center of the weld joint, the laser power is in a low-high-low change trend in the direction from the upper plate to the center of the weld joint to the lower plate, and it is ensured that the laser in the center of the weld joint can penetrate through the upper plate. Laser on the two sides of the center of the welding seam is controlled in a state of not penetrating through the plate, so that energy input in different subareas of the welding seam is accurately controlled, the controllable and different fusion depths of all the subareas are ensured, the problems that the fusion depths are unstable, the contour of a molten pool is discontinuous and the lower plate is easy to penetrate are solved, the welding seam is good in consistency and free of inward concave or outward convex, and continuous smooth transition is achieved; the size measurement of the molten pool meets the standard requirements, the welding quality and the welding efficiency are effectively improved, welding wires are not needed, and the cost is effectively reduced.

The invention relates to the technical field of copper alloy contacts, in particular to a method for modifying the surface of a copper-chromium contact by adopting a surface laser remelting technology. Comprising the following steps: S1, carrying out sand blasting treatment on the copper-chromium contact; s2, carrying out laser remelting on the copper-chromium contact subjected to sand blasting treatment; and S3, the copper-chromium contact obtained after laser remelting is placed in magnetic grinding equipment, grinding treatment is conducted for 8-12 min, and the modified copper-chromium contact is obtained. The surface of the copper-chromium contact is modified through the laser remelting technology, refining of chromium phase particles can be effectively promoted, and a continuous and compact fine grain strengthening layer with a certain thickness is constructed on the surface layer of the alloy, so that the voltage resistance strength, the breaking capacity and the fusion welding resistance of the copper-chromium contact are comprehensively enhanced.