18results about How to "Low dilution rate" patented technology

The invention provides a mold surface repairing method and system based on laser cladding, and relates to the technical field of laser cladding, the method comprises the following steps: selecting a matrix material with a proper size, and pretreating the surface of the matrix material; according to the actual process requirements, the value range of laser cladding process parameters is determined, and a response curved surface model of the microhardness and the dilution rate is established; optimizing the response curved surface model, and obtaining an optimized process parameter combination by taking maximization of microhardness and minimization of dilution rate as targets; according to the optimized technological parameter combination, the laser cladding process is carried out, and a cladding layer is formed on the pretreated base material; and performing performance detection on the formed cladding layer, and adjusting process parameters according to a performance detection result until an optimal process parameter combination is determined. By means of the method, it can be guaranteed that the hardness of the cladding layer is stabilized within the ideal range, the mold repairing quality is remarkably improved, and the service life of the mold is remarkably prolonged.

The embodiment of the invention provides a preparation method of a sliding bearing composite coating and the sliding bearing composite coating, and relates to the technical field of surface engineering.The method comprises the steps that nickel-based base coat alloy powder and copper-based alloy surface layer powder are dried; a cladding head is aligned with a to-be-cladded area of the sliding bearing, nickel-based priming layer alloy powder is evenly fed into the surface, aligned with the cladding head, of the sliding bearing through a scraping disc type pressure powder feeder on the basis of first technological parameters, the nickel-based priming layer alloy powder is molten into molten drops, and the molten drops and the surface of the sliding bearing form a micro molten pool; carrying out continuous cladding to form a nickel-based bottoming layer; and after the sliding bearing with the surface cladded with the nickel-based bottom layer is cooled, the nickel-based bottom layer is polished to be smooth, copper-based alloy surface layer powder is evenly fed into the surface of the nickel-based bottom layer through a scraping disc type pressure powder feeder on the basis of second technological parameters, and the copper-based alloy surface layer is formed on the surface of the nickel-based bottom layer through continuous cladding. And the sliding bearing clad with the composite coating is obtained. The quality can be improved.

The invention discloses a welding method for a nickel-based alloy composite board. The nickel-based alloy composite board comprises a base material layer and a nickel-based alloy composite material layer, and a transition layer is arranged at the bonding interface of the base material layer and the nickel-based alloy composite material layer. Wherein a trapezoidal groove is machined in the position, corresponding to the base material layer, of the welding section of the nickel-based alloy composite board; a U-shaped groove is machined in the position, corresponding to the transition layer, of the welding section of the nickel base alloy; a groove is not machined in the position, corresponding to the nickel-based alloy composite material layer, of the welding section of the nickel-based alloy composite plate; a nickel-based alloy welding wire matched with the nickel-based alloy composite material layer is used, single argon tungsten-arc welding is adopted for welding the nickel-based alloy composite material layer, and a composite material layer welding seam is formed; a nickel-based alloy welding wire matched with the nickel-based alloy composite material layer is used, the transition layer is welded through single argon tungsten-arc welding, and a transition layer welding seam is formed; and the base material layer is welded to form a base material layer welding seam, and double-tungsten-electrode argon arc welding is adopted for welding the first welding bead of the base material layer.

The invention discloses a welding gun for argon arc welding, and belongs to the technical field of welding guns for surfacing, the welding gun comprises a welding torch, an electrode mounted in the welding torch and a welding wire conveying device synchronously moving with the electrode, a first through hole is formed in the electrode, and the first through hole extends in the axial direction of the electrode and penetrates through the two ends of the electrode; the welding wire conveying device comprises two wire feeding pipes used for conveying welding wires, all the wire feeding pipes are located on the same side of the welding direction, the two wire feeding pipes are symmetrically arranged relative to the electrode, and the tail ends of all the wire feeding pipes point to the electrode; compared with a double-tungsten-electrode welding gun, the size of the welding gun can be reduced, and the welding gun is suitable for welding small-pipe-diameter workpieces; compared with a solid tungsten electrode, the hollow tungsten electrode can reduce the arc pressure in the welding process in the same large-current welding process so as to reduce the forming probability of a hump weld bead; the welding efficiency can be improved, the dilution rate can be reduced, interference to welding arcs can be reduced, and the welding stability is improved through double-path wire feeding.

The invention discloses a welding material for preparing an aluminum-steel gradient structure. The welding material comprises alloy powder for laser cladding and an aluminum-based welding wire for CMT welding. The alloy powder for laser cladding comprises the following components in percentage by mass: 20.0%-30.0% of Zn powder, 20.0%-30.0% of Cu powder, 5.0%-10.0% of Si powder, 5.0%-10.0% of Sn powder and the balance of Al, the aluminum-based welding wire for CMT welding comprises powder and a welding skin, and the powder comprises, by mass, 20.0%-30.0% of Zn powder, 20.0%-30.0% of Ag powder, 10.0%-20.0% of Cu powder, 5.0%-10.0% of Si powder, 5.0%-9.0% of Mg powder and the balance Al powder. The structure solves the problems of cracking and poor performance caused by mismatching of thermal physical properties and brittle phases of an aluminum-steel dissimilar structure. The invention further provides a laser and CMT composite preparation method of the aluminum-steel gradient structure.

The invention provides a boride reinforced light refractory high-entropy alloy coating, and belongs to the technical field of alloy surface coating modification. The preparation method comprises the following steps: (1) preparing the following components in atomic percent: 24.39-25% of Al; the content of Nb is 24.39 to 25 percent; ti: 24.39%-25%; v: 24.39% to 25%; b, weighing 0-2.44% of each powder, mixing, and carrying out ball milling to obtain mixed alloy powder; (2) the surface of the titanium alloy matrix is pretreated; and (3) the mixed alloy powder is dried and then preset on the surface of a pretreated titanium alloy matrix to form a prefabricated layer, then laser cladding is conducted to obtain the boride reinforced light refractory high-entropy alloy coating, metallurgical bonding is formed between the coating and the matrix, obvious cracks and holes do not exist, the macroscopic morphology is good, the microstructure is mainly a dendritic structure, and the heat conductivity is high. The above shows that an expected effect is achieved. The high-entropy alloy coating obtained by the process improves the strength and wear resistance of the titanium alloy, so that the high-entropy alloy coating can be applied to aerospace, rail transit or marine ships and has a wider application prospect.

The invention provides a collaborative optimization method for a magnetic-thermal composite field assisted laser cladding process. According to the method, a magnetic-thermal composite field-assisted laser cladding device is designed based on an energy field-assisted laser cladding process principle and is used for improving the structure and performance of a coating; the method comprises the following steps: generating a quadratic polynomial regression model on the basis of an RSM method, magnetic-thermal composite field assisted laser cladding process parameters and nickel-based composite coating quality evaluation indexes, performing multi-target optimization on the coating quality evaluation indexes on the basis of the quadratic polynomial regression model and an IMOGWO algorithm, determining a magnetic-thermal composite field assisted laser cladding target process parameter combination, and determining the quality of the nickel-based composite coating. And score calculation is carried out on the target process parameter combination based on an EWM-TOPSIS method to obtain a comprehensive evaluation sequence of the target process parameter combination, so that collaborative optimization of the magnetic-thermal composite field assisted laser cladding process is realized, and the performance optimization efficiency and quality of the nickel-based composite coating are improved.

According to the wear-resistant and corrosion-resistant CoCrFeNiMoTi high-entropy alloy coating, commercial CoCrFeNiMo high-entropy alloy powder with the equal atomic ratio serves as a powder raw material, TA15 titanium alloy serves as a base material, and the wear-resistant and corrosion-resistant CoCrFeNiMoTi high-entropy alloy coating is printed on the surface of the base material in a snakelike reciprocating single-layer printing mode by means of laser melting deposition and base material preheating. The prepared high-entropy alloy coating is good in metallurgical bonding with a TA15 titanium alloy base material, has no defects such as cracks and air holes, has high hardness and excellent wear resistance and corrosion resistance, and has a wide application prospect.

The present invention provides a method for manufacturing a cylinder inner hole by high-speed laser cladding, comprising the following steps: the first part: processing before cladding: the key part is not processing the inner surface of the threaded section, keeping the threaded section consistent with the scraping surface, turning the first chamfer on the left end face of the threaded section to transition to the first step, and then continuing to turn the second chamfer to transition to the scraping surface; the second part: high-speed laser cladding of the inner hole: setting the cladding path to: scraping surface, the second chamfer on the right side of the scraping surface, the first step, the first chamfer, the inner surface of the threaded section, the stop and the chamfer on the right end of the stop to clad one layer; remelting one layer at each chamfer; the third part: finishing after high-speed laser cladding; the fourth part: welding the cylinder bottom. The high-speed laser cladding manufacturing method for the inner hole of the oil cylinder meets the requirements of the inner hole cladding of the oil cylinder, has small deformation and high precision.

This invention discloses a method for in-situ laser-arc composite cladding of boiler heating surfaces, relating to the field of laser beam processing technology. The method includes: removing the corrosion layer and oxide film from the area to be repaired using dry ice blasting and laser; maintaining water cooling on the back side of the area to be repaired; pausing after each cladding section to allow the interlayer temperature to drop to 200℃-250℃; sequentially cladding the underlayer, transition layer, and wear-resistant layer; after each cladding layer is completed, the surface is treated with laser shock peening; when an abnormal enhancement of the Fe I spectral line at 435.2 nm is observed, it is determined to be "excessive dilution"; when a high-frequency burst signal of 80kHz-120kHz appears in the acoustic emission signal, it is determined to be "microcrack formation". This invention enables rapid repair of large-area heating surfaces with high bonding strength, low heat input, and no cracks, under in-situ boiler conditions without disassembly, overall preheating, and with a cooling medium on the back side.

The invention discloses a welding strip preheating device of a strip surfacing welding gun. The device comprises a strip surfacing machine head, flux hoppers, a welding strip and a contact tube, a preheating device is arranged below the strip surfacing machine head, the welding strip vertically and downwards enters a gap between a fixed heat insulation plate and an adjustable heat insulation plate of the preheating device along the contact tube of the strip surfacing machine head, and the flux hoppers are arranged on the two sides of the lower end of the preheating device; a connecting plate, a fixed thermal insulation plate, an adjustable thermal insulation plate and a cover plate of the preheating device are sequentially arranged in the transverse direction. And the connecting plate and the cover plate are fixedly connected with the strip surfacing machine head. The device has the beneficial effects that the structural design is reasonable, the operation is easy, the dry extension length of the welding strip can be effectively increased, the welding strip is effectively preheated by utilizing resistance heat of the dry extension part of the welding strip, the cladding speed of the welding strip in unit current is obviously improved, and the surfacing speed is improved; the purposes of reducing welding line energy, increasing the cooling speed of a surfacing layer, reducing the dilution rate of base metal and improving the mechanical properties and metallographic structures of the surfacing layer and a heat affected zone are achieved.

The invention belongs to the technical field of welding, and particularly relates to a single-tungsten high-current high-frequency double-pulse double-hot-wire surfacing method. The high-frequency double-pulse current is adopted as the main welding current for welding, meanwhile, the pulse frequency of the large pulse current stage and the pulse frequency of the small pulse current stage are limited to be larger than or equal to 5000 Hz, the arc pressure can be reduced along with increase of the pulse current frequency, and therefore large-current welding can be carried out when the arc voltage is controlled to be smaller than or equal to 25 V; therefore, the occurrence of hump welding beads in high-speed welding is reduced. According to the method, high-frequency double-pulse current is adopted, the distance between molten pools can be effectively reduced, and therefore the incomplete fusion defect is not prone to occurring; and meanwhile, the high-frequency double-pulse current can cause molten pool oscillation, and the effects of refining crystal grains and reducing air holes are achieved. Compared with single-path wire feeding, two-path wire feeding is adopted, the cladding rate is higher, the dilution rate is lower, and practical significance is achieved for surfacing application.

The utility model discloses an underwater grouting head and grouting device, underwater grouting head includes inner casing, outer casing and apron, the inner casing has a grouting chamber, and the grouting chamber is provided with grout inlet and grout outlet on it and communicates, the outer casing is covered on the lateral wall of inner casing, and the medium cavity is formed between the inner lateral wall and the lateral wall of inner casing, and the medium inlet and medium outlet that communicate with the medium cavity are arranged on it, and the medium outlet ring is arranged in the side of grout outlet, the apron is the horn -like structure, and has deformability. The utility model has the advantages of: this underwater grouting head is isolated from the water flow through air curtain or water curtain barrier and apron, reduces the slurry dilution rate, makes the slurry coagulation in low disturbance environment, improves the grouting body compactness and the bonding strength, promotes the construction quality, and the whole underwater grouting head has no electronic component, is suitable for deep water environment, and the manufacturing cost is low.

The preparation method comprises the following steps that S1, a base pipe is polished, oxide skin on the surface of the base pipe is removed, the surface of the base pipe is cleaned with absolute ethyl alcohol to remove stains, and the base pipe is dried with cold air; and S2, circulating cooling water is conveyed into the base tube, and meanwhile, under the action of a heat source laser beam, Ni-based alloy powder is cladded to the surface of the base tube. According to the composite pipe prepared through the method, the high-temperature molten salt corrosion resistance is effectively improved and is about 5 times that of a base pipe, the service life of a furnace pipe is prolonged, the operation rate of a generator set is increased, and the power generation cost of a waste incineration power plant is greatly reduced.

The application discloses a DPF regeneration control method and device, comprising the following steps: obtaining engine speed, fuel injection quantity and fuel injection pressure; determining the maximum limited fuel injection quantity of post-injection 1 according to the engine speed and fuel injection quantity by inquiring a first inquiry table, wherein the first inquiry table stores engine speed, fuel injection quantity and corresponding maximum limited fuel injection quantity of post-injection 1; determining the post-injection 1 segmentation times according to the maximum limited fuel injection quantity of post-injection 1 and the fuel injection pressure by inquiring a second inquiry table, wherein the second inquiry table records the maximum limited fuel injection quantity of post-injection 1, fuel injection pressure and corresponding post-injection 1 segmentation times; and calculating the single post-injection 1 fuel injection quantity according to the maximum limited fuel injection quantity of post-injection 1 and the post-injection 1 segmentation times. The method of the application divides the post-injection 1 fuel injection quantity, which not only ensures that the DPF regeneration temperature meets the requirements, but also reduces the diesel engine oil dilution rate.

The utility model relates to welding equipment, in particular to a welding gun device with a double-tungsten-electrode double-wire mechanism. The welding gun device with the double-tungsten-electrode double-wire mechanism is good in welding stability, high in welding efficiency and low in dilution rate. The welding gun device with the double-tungsten-electrode and double-wire mechanism comprises an insulating holder and a hot wire support, a first welding gun and a second welding gun are arranged in the insulating holder, a first tungsten electrode is arranged in the first welding gun, a second tungsten electrode is arranged in the second welding gun, and gas protection channels are arranged on the outer sides of the tungsten electrodes. A water-cooling gas protection plate and a water-cooling gas protection cover are arranged below the insulation retainer, a tungsten electrode penetrates through the water-cooling gas protection plate and the water-cooling gas protection cover, a first wire feeding mechanism and a second wire feeding mechanism are arranged on the hot wire support, and a first welding wire and a second welding wire are arranged on the first wire feeding mechanism and the second wire feeding mechanism respectively. The head of the first welding wire and the head of the second welding wire are opposite and located below the first tungsten electrode and the second tungsten electrode.

The present application relates to a kind of full amorphous no crack iron-based amorphous coating of ultra-high speed laser cladding and preparation method.To be cladded workpiece is preheated, and the workpiece to be cladded that is preheated is clamped with chuck, and is placed on rotating carrier;Adjust the powder feeding speed of cladding device, carrier gas flow, shielding gas flow;Adjust the distance between cladding head and the workpiece to be cladded, laser focal point, powder flow focal point, set the moving speed of cladding head;Rotating carrier drives the workpiece to be cladded to rotate, and from outside to inside, laser cladding is started, and the full amorphous no crack iron-based amorphous coating of ultra-high speed laser cladding is formed on the surface of the workpiece to be cladded.The present application controls the process parameters of ultra-high speed laser cladding, and selects the parameters suitable for processing amorphous coating, realizes the rapid cooling of coating and defect-free preparation while ensuring the complete amorphous of coating.The coating has high corrosion resistance and excellent mechanical properties.

The present invention discloses a balancing device for a multi-stage pump and a surface additive manufacturing method, wherein the balancing device comprises a balancing disk; the balancing disk comprises a cylindrical shaft barrel portion and a disc portion axially perpendicular to the shaft barrel portion; the shaft barrel portion and the disc portion are axially connected; the outer peripheral surface of the shaft barrel portion is a matching A surface; a matching B surface surrounding the matching A surface is relatively arranged in the outer clearance of the matching A surface; a circular matching C surface is arranged on the disc surface of the disc portion; a matching D surface parallel to and opposite to the matching C surface is arranged on the balancing device; and a laser cladding layer is laser clad on the matching A surface, the matching B surface, the matching C surface and the matching D surface. The present invention meets the working condition requirements of the surface of the balancing device parts through material changes and process changes, realizes various hardening, corrosion and wear resistance requirements of the surface of the stainless steel substrate, and realizes low-cost high-tech product manufacturing.