731 results about "Alloy surface" patented technology

The invention provides an aluminum alloy surface oxidation spot defect identification method and device based on machine vision, and relates to the field of intelligent manufacturing and industrial automation, and the method comprises the steps: obtaining an aluminum alloy surface color image, and carrying out the preprocessing of the image, so as to extract a brightness component image; self-adaptive threshold segmentation of local contrast enhancement is carried out on the brightness component image, a defect area binary mask is generated, morphological connected domains are extracted according to the mask, and three basic feature indexes of the area pixel value, the contour Fourier descriptor complexity and the area gray scale standard deviation contrast of each connected domain are calculated; and extracting and marking a connected domain boundary, verifying a boundary closed topological structure, and dynamically generating a curvature-driven self-adaptive sampling point through multi-scale B-spline curvature extreme value detection. Through optical-algorithm-process three-level collaborative innovation, the curved surface reflection false alarm rate is reduced, the pinhole detection rate is increased, and the boundary precision is + / -0.2 pixel.

The invention belongs to the technical field of electroplating process optimization, and particularly discloses a titanium alloy surface electroplating control method which comprises the following steps: dynamically generating a hanger posture configuration scheme based on workpiece three-dimensional contour data acquired in real time; a bubble distribution image and electroplating liquid flow field data are synchronously collected, and a bubble-flow field coupling feature set is generated through multi-modal fusion; performing real-time linkage adjustment on the rotation speed and the swing amplitude of the workpiece according to the coupling feature set; after electroplating is completed, plating thickness, edge integrity and surface defect data are collected, and a multi-source plating data set is formed by combining workpiece position information; historical data and real-time data are integrated to carry out hanger layout adjustment judgment, and hanger spacing dynamic reconstruction optimization is started when adjustment is needed. According to the method, multi-parameter cooperative control and closed-loop quality optimization in the electroplating process are achieved, the uniformity and integrity of a titanium alloy workpiece coating are remarkably improved, and generation of bubble related defects is effectively restrained.

The invention relates to the field of three-dimensional vision measurement, in particular to an aluminum alloy CNC product defect detection method and system based on structured light scanning. The aluminum alloy CNC product defect detection system based on structured light scanning comprises an image acquisition and analysis module, a self-adaptive illumination control module, a point cloud reconstruction module, a defect detection module and a report generation module. According to the method, through texture direction perception and matrix type light source dynamic angle modulation, and in combination with a light intensity-wavelength self-adaptive scheme of saturated pixel grading, mirror surface glare of the aluminum alloy high-reflection surface is greatly reduced; in cooperation with multi-exposure gray scale weighted fusion, a stripe image which is uniform in contrast and free of overexposure can be obtained in single scanning; in the same scanning time, compared with a fixed illumination scheme, the point cloud integrity rate can be improved, and a more reliable three-dimensional data basis is provided for subsequent defect detection.

The invention discloses a niobium-titanium-tungsten alloy based on 3D printing, a gradient material of the niobium-titanium-tungsten alloy and a preparation method of the niobium-titanium-tungsten alloy. Mixed powder is used as a raw material, and short-process and low-cost preparation of the niobium-titanium-tungsten alloy can be achieved through multiple additive manufacturing methods. By utilizing the ratio of the pre-alloyed powder with different impurity contents, the performance of the niobium-titanium-tungsten alloy can be effectively regulated and controlled through various additive manufacturing methods; a niobium-titanium alloy coating is cladded on the surface of the niobium-titanium-tungsten alloy to form a gradient material, and the corrosion resistance of the niobium-titanium-tungsten alloy can be improved on the premise that the performance of a niobium-titanium-tungsten matrix is not obviously changed.

The invention provides a titanium alloy-based composite coating structure, a method for inhibiting upward dilution of Ti during cladding of a wear-resistant layer on the surface of a titanium alloy and application of the titanium alloy-based composite coating structure. The method comprises the steps that an aluminum bronze barrier layer is formed on a titanium alloy substrate, the phase structure of the aluminum bronze barrier layer comprises a Cu phase and a Cu2TiAl phase, the Cu phase and the Cu2TiAl phase are each of an FCC crystal structure, and the Cu2TiAl phase is formed by reacting Ti in the titanium alloy substrate with Cu and Al; the volume ratios of a Cu phase and a Cu2TiAl phase in the aluminum bronze barrier layer are 40%-45% and 55%-60% respectively; and forming the transition alloy wear-resistant layer on the titanium alloy substrate with the aluminum bronze barrier layer by adopting a laser cladding technology. The aluminum bronze barrier layer is arranged to reduce upward dilution of Ti elements in the cladding process of the transition alloy wear-resistant layer, generation of a large number of hard brittle phases is avoided, the difference between the wear-resistant layer and a titanium alloy matrix in the thermophysical property aspect is relieved, and coating cracking is reduced.

The invention relates to the technical field of coatings, in particular to a coating suitable for niobium-silicon alloy surface high-temperature protection and a preparation method of the coating. The coating comprises the following raw materials in parts by weight: 100-120 parts of deionized water, 60-80 parts of nickel-chromium-aluminum-yttrium alloy powder, 60-80 parts of enamel glaze, 50-60 parts of filler, 20-40 parts of a binder, 10-20 parts of nano titanium dioxide and 6-10 parts of an additive. According to the invention, during preparation of the coating, through addition of the filler, the negative thermal expansion performance of zirconium tungstate in the filler and volume shrinkage of zirconium tungstate in a high-temperature state, a buffer space is provided for thermal expansion of other materials in the coating, cracks of the coating due to thermal stress are avoided, and the high-temperature resistance of the coating is improved; kH560 enhances the interfacial compatibility of zirconium tungstate, avoids agglomeration of zirconium tungstate, and enables the zirconium tungstate to be more uniformly distributed in a coating system.

The application discloses an aluminum alloy surface fine polishing polishing composition, polishing liquid and application thereof, and particularly belongs to the technical field of metal surface treatment. The polishing composition comprises the following components in mass fraction: 70-80 parts of silica sol, 1-4 parts of dispersing agent, 5-7 parts of surfactant, 5-10 parts of corrosion inhibitor, and 0.5-2 parts of water-retaining agent; and the surfactant is composed of perfluoropolyether, coconut oil alkylolamide and sodium dodecyl benzene sulfonate. The polishing composition provided by the application has high polishing efficiency, can reduce polishing cost, improve product quality, has low material surface roughness and few scratches after polishing treatment, effectively improves the polishing surface quality, improves the overall appearance and durability of the material, and the polishing liquid does not contain toxic substances such as chromium / phosphorus, and is environment-friendly.

The invention discloses a method for acquiring grain orientation characteristics based on optical and height characteristics of an alloy etching structure. The method comprises the following steps: (1) acquiring grain orientation distribution and grain size of an alloy surface structure; (2) obtaining an etching structure on the surface of the alloy; (3) acquiring optical characteristics of the etched structure on the surface of the alloy; (4) obtaining height characteristics of an alloy surface etching structure; and (5) constructing a correlation model of structure grain orientation characteristics based on alloy surface optics and height characteristics, and realizing prediction. Aiming at the test of the alloy grain orientation, the optical and height characteristics of the alloy surface etching structure are synthesized, the measurement of the centimeter-level large sample size or full-area grain orientation of the alloy is easy to realize, and compared with the existing measurement aspect, the method is more efficient and convenient; and more comprehensive and reliable tissue information can be provided for alloy optimization and new material development, and the method has important significance for high-throughput characterization and intelligent manufacturing.

The invention relates to the technical field of metal material surface strengthening and modification, in particular to a preparation method and process of a titanium alloy laser cladding cobalt-based wear-resistant coating. The invention provides a titanium alloy surface laser cladding cobalt-based wear-resistant coating which takes titanium or a titanium alloy as a base material, comprises the following components in percentage by weight: 40-50% of cobalt (Co), 30-40% of tungsten carbide (WC), 10-15% of chromium (Cr), 1-5% of lanthanum hexaboride (LaB6), 2-5% of silicon (Si) and 0.5-3% of calcium fluoride (CaF2), and has the beneficial effects of improving wear resistance, high-temperature stability, corrosion resistance, high hardness, high bonding strength, difficulty in cracking and the like.

To provide an Fe-Ni-Cr alloy that can suppress intergranular cracking (nitriding resistance) and also inhibit the formation of red scale (oxidation resistance) even in a gas atmosphere containing nitrogen and water vapor, such as ammonia combustion gas, at a medium-high temperature range of 500 to 700°C.SOLUTION: The present invention relates to an Fe-Ni-Cr alloy that has a predetermined component composition, a nitriding resistance index of 81 or higher, and 3.0 or more of fine crystalline grains with a grain size of 0.5 μm or less present in the plate thickness direction in the alloy surface layer. The Fe-Ni-Cr alloy is obtained by introducing strain (transformation) on the surface of the alloy material by polishing or the like, then performing heat treatment, and generating fine crystalline grains using the introduced strain (transformation) as a driving force. Nitriding resistance index: Cr+3Ni-10Mo≥81.SELECTED DRAWING: None

The invention discloses an aluminum alloy surface defect identification method and system. The method comprises the following steps: acquiring surface initial detection information of an aluminum alloy part; constructing an initial detection surface feature reference library based on the surface initial detection information; acquiring a reinspection image when the aluminum alloy component is reinspected; in the areas to be analyzed in a candidate mode, whether abnormal changes happen to the surface permissible area and the initial defect area in the reinspection image or not is judged, and the areas to be analyzed in the candidate mode which do not have the abnormal changes are excluded from new defect detection; and obtaining a to-be-detected new defect area, and performing structure differentiation comparison on the to-be-detected new defect area based on the global feature relationship between the redetection image and the initial detection image to identify new defect parameters. According to the embodiment of the invention, the method can effectively utilize the initial detection information, distinguishes the newly generated defects from the original surface features or allowable flaws of the part, reduces the false alarms, and improves the detection efficiency and accuracy.

The invention discloses a chemically enhanced shear thickening polishing solution suitable for a WC-Co alloy and a polishing method, and aims to solve the problem of loss of a Co phase on the surface of the WC-Co alloy in a traditional polishing method. The polishing solution comprises K3 [Fe (CN) 6], KOH, diamond abrasive particles, dispersed phase particles and deionized water, a WC phase and a Co phase of a WC-Co alloy react with [Fe (CN) 6] 3 <-> and OH <-> in the polishing solution respectively, and a soft oxidation film WO3-x and a stable Co3O4 oxidation film are generated on the surface of the alloy. Through the shear thickening effect, the polishing solution forms a particle cluster wrapping the abrasive particles when the relative speed reaches a threshold value, a surface oxidation film is removed through the micro-cutting effect of the diamond abrasive particles, and efficient, high-quality and Co-loss-free WC-Co alloy surface polishing is achieved. The method obviously inhibits the loss of the Co phase at the same time, maintains the hardness and the use performance of the alloy surface, and is especially suitable for precision machining of the hard alloy blade.

The invention discloses a method for improving the oxidation resistance of nickel-based superalloy, and belongs to the technical field of metal material surface modification. Based on the high-energy transient effect of laser shock waves, the method mainly comprises the key steps of alloy surface pretreatment, laser shock peening process implementation, post-treatment and the like. Specifically, firstly, the surface of the nickel-based single crystal alloy is subjected to pretreatment such as polishing and cleaning, surface defects and pollutants are removed, and the treatment quality is guaranteed; then, according to the material characteristics and performance requirements of the nickel-based single crystal alloy, laser parameters such as laser energy, pulse width and light spot diameter are accurately set, and proper restraint layer and absorption layer materials are selected; then, high-energy pulse laser is utilized to irradiate the absorption layer, high-temperature and high-pressure plasma is induced to be generated, the plasma expands and explodes to generate strong shock waves, the shock waves act on the alloy surface, the surface material is subjected to severe plastic deformation, a residual compressive stress layer with the depth capable of reaching hundreds of micrometers is formed, meanwhile, surface grains are refined, and the microstructure is optimized; and after the strengthening treatment is completed, simple cleaning and performance detection post-treatment are carried out. Through laser shock strengthening, a special organization structure with high density and low defect density is formed on the surface of the nickel-based single crystal alloy, diffusion and invasion of oxygen atoms are effectively hindered, and the oxidation resistance of the alloy is remarkably improved. According to the method, the controllability of technological parameters is high, the strengthening effect can be accurately regulated and controlled, the treatment process is free of pollution and high in efficiency, the obtained strengthened nickel-based single crystal alloy can be widely applied to the fields such as aerospace engine hot end parts and nuclear energy equipment which have strict requirements for high-temperature oxidation resistance, the reliability of related parts is greatly improved, and the service life of the related parts is greatly prolonged.

The invention discloses a surface defect detection method and system based on aluminum alloy for aerospace, and belongs to the technical field of aluminum alloy. The method comprises the following steps: acquiring first image data of a to-be-detected aluminum alloy, wherein the first image data is image data acquired by a depth camera; controlling a polarized light source to irradiate the to-be-detected aluminum alloy according to the first image data, and controlling a polarization camera to collect second image data; determining target fusion image data according to the first image data and the second image data; and identifying a defect detection result of the to-be-detected aluminum alloy according to the target fusion image data. The technical effect of improving the accuracy of quality detection of the aluminum alloy surface is achieved.

The invention belongs to the technical field of aluminum alloy surface treatment, and discloses an aluminum alloy micro-arc oxidation film layer with high plasma fluorination environment resistance and a preparation method thereof.The aluminum alloy serves as a matrix, the micro-arc oxidation film layer with high plasma fluorination environment resistance is formed on the surface of the matrix, the thickness of the film layer is 10-50 micrometers, the porosity is 3-5%, and the thickness of the film layer is 10-50 micrometers. The pore diameter is 0.5-1 [mu] m, and the alpha-Al2O3 accounts for 60-80%. According to the film layer, generation of more compact Al2O3 is promoted by adding zircon salt and yttrium salt, the structure and performance of the film layer are improved through introduced zirconium and yttrium elements, and the film layer has the advantages of being high in hardness, low in porosity, high in corrosion resistance and high in wear resistance.

The invention relates to the technical field of metallurgy preparation of heterogeneous materials, in particular to an efficient laser cladding preparation method of nickel-based superalloy on the surface of copper alloy, which comprises the following steps: increasing the absorptivity of the copper alloy to infrared laser through preheating, and carrying out laser cladding on GH3625 alloy on the surface of Cu-Cr-Zr alloy through regulating and controlling the components of a copper alloy / nickel alloy intermediate layer, so as to prepare the nickel-based superalloy on the surface of Cu-Cr-Zr alloy. And formation of a microstructure in the non-equilibrium solidification process is controlled, the process is optimized, and the mechanical property of the material is improved. According to the method, the intermediate layer is utilized to perform non-equilibrium state metallurgy preparation of the GH3625 alloy on the surface of the Cu-Cr-Zr base material, compared with the method without adding the intermediate layer, after the intermediate layer is added, the content of the copper element in a molten pool is increased, liquid-phase separation is promoted, a large-range Ni-Cr core shell is formed to serve as a low-energy nucleation site, crystal grains are refined, and the performance of the Cu-Cr-Zr alloy is improved. Further, a fine grain strengthening effect is achieved; the thickness of the element diffusion layer is also increased by adding the middle layer, the element uniformity is promoted, the dependence on Malangori is reduced, the heat input is reduced, the optimization of process parameters is realized, and the mechanical property of the heterogeneous material is further improved.

The invention discloses a preparation method of a double-response self-repairing super-hydrophobic coating on the surface of an aluminum alloy. The preparation method is specifically implemented according to the following steps: step 1, preparing sea urchin-shaped photo-thermal particles Fe3O4-at-TiO2; step 2, preparing self-repairing porous boron nitride; 3, preparing thermal response particles by an emulsion method; step 4, carrying out photocuring and dynamic disulfide bond crosslinking modification; and 5, preparing the double-response self-repairing super-hydrophobic coating. The invention also discloses the coating prepared by the method, the light absorption area is increased by preparing the sea urchin-shaped Fe3O4-coated TiO2, and after the two materials form a heterojunction, absorption spectrums complement each other, so that the energy of sunlight can be more efficiently utilized, and the photothermal conversion efficiency is improved. Porous boron nitride (PBN) increases the specific surface area, loads more perfluoropolyether and forms a continuous heat conduction channel through a porous framework to improve the heat conductivity, it is guaranteed that heat can be transmitted to the thermal response shell to the maximum extent, and the thermal response efficiency is improved.

The invention discloses a preparation method of a molten salt corrosion resistant coating on the surface of a TiAl alloy, relates to the technical field of surface treatment, and aims to solve the technical problems of low binding force between an existing TiAl alloy matrix and a coating interface and poor corrosion resistance of the coating. The preparation method of the molten salt corrosion resistant coating on the surface of the TiAl alloy comprises the steps that a Zr-Y alloy is infiltrated on the surface of the TiAl alloy through a double glow plasma method, and a Zr-Y infiltrated layer is formed on the surface of the TiAl alloy; the TiAl alloy is subjected to heat preservation for 1-5 hours under the condition that the temperature ranges from 850 DEG C to 900 DEG C; a Zr-Cr-Y alloy is infiltrated on the surface of the TiAl alloy, and a Zr-Y / Zr-Cr-Y infiltrated layer is formed on the surface of the TiAl alloy; the TiAl alloy is subjected to heat preservation for 2-3 hours under the condition that the temperature ranges from 900 DEG C to 950 DEG C, and is oxidized under the condition that the temperature ranges from 860 DEG C to 920 DEG C;

The invention discloses a hydrothermal passivation method for a calcium carbonate film layer on the surface of a magnesium alloy, and belongs to the technical field of magnesium alloy surface treatment.The hydrothermal method is adopted for conducting passivation treatment on the magnesium alloy coated in a water bath, a new compact layer is formed under an original calcium carbonate deposition film with defects, and internal passivation of the coated magnesium alloy is achieved. And the corrosion resistance of the coated magnesium alloy is obviously enhanced.

The invention discloses a corrosion-resistant high-entropy alloy surfacing layer for the surface of marine structural steel and a preparation method of the corrosion-resistant high-entropy alloy surfacing layer, and belongs to the technical field of structural steel. The preparation method comprises the following steps: (1) Co powder, Cr powder, Fe powder, Ni powder and Mo powder are mixed and then subjected to ball milling, and CoCrFeNiMo powder is obtained; (2) the metal matrix plate to be treated is subjected to alkali washing and then subjected to surface sand blasting roughening treatment till rough silver gray metal luster appears on the surface; and (3) a CoCrFeNiMo powder material serves as a raw material, plasma arc powder surfacing is conducted on the surface of the metal matrix plate subjected to sand blasting roughening, and the corrosion-resistant high-entropy alloy surfacing layer is obtained. The high-entropy alloy surfacing layer is high in bonding strength with a matrix, high in density, extremely low in porosity, excellent in corrosion resistance and capable of spontaneously resisting seawater corrosion, a passive film has high stability and pitting corrosion resistance, and the whole surfacing layer has good comprehensive corrosion resistance.

The invention belongs to the technical field of aluminum alloy surface treatment, and particularly relates to a composite gradient preparation method of an aluminum alloy surface wear-resistant coating, which comprises the following steps: pretreating the aluminum alloy surface, preparing an injection layer with the thickness of 0.05-0.09 mm by adopting a supersonic gas power injection technology, and preparing a transition layer with the thickness of 0.5-0.8 mm by adopting a cold spraying technology, the transition layer is subjected to post-treatment by adopting a laser diffusion technology, and finally, alloy coated powder is cladded on the surface of the transition layer by adopting an ultra-high-speed laser cladding technology, so that the wear-resistant coating with the thickness of 0.7-1.2 mm is prepared; by means of the method, the problems that in the existing aluminum alloy laser cladding layer preparation process, the laser reflectivity is high, a molten pool cannot be effectively formed, the cladding layer dilution rate is high, and air hole defects exist are solved.

The invention discloses a titanium-aluminum alloy defect detection device and method.According to the titanium-aluminum alloy defect detection device, a micro-texture film is attached to the surface of a detected workpiece in the defect detection process, so that a known interference source is introduced, and the defect detection accuracy is improved by combining a forward and reverse constant-speed scanning strategy; signal processing is carried out after the forward phase domain response signal and the reverse phase domain response signal are obtained, and a real defect signal can be accurately extracted, so that a surface roughness interference signal can be effectively eliminated on the premise that the surface of a workpiece is not damaged, the detection rate of titanium-aluminum alloy surface and near-surface defects is improved, the false detection rate is reduced, and the detection efficiency is improved. And high resolution and high signal-to-noise ratio are maintained.

The invention discloses a nickel-based alloy surface laser cladding coating and a preparation method thereof, and belongs to the technical field of alloy coating preparation. The preparation method of the nickel-based alloy surface laser cladding coating comprises the following steps that MoNiSi / La2O3 powder is subjected to ball milling, and pretreated powder is obtained; the nickel-based alloy base material is subjected to solid solution aging heat treatment, cleaned and dried, and a pretreated base material is obtained; and a binding agent and the pretreated powder are mixed and then laid on the surface of the pretreated base material for laser cladding, then aging heat treatment is conducted, and the nickel-based alloy surface laser cladding coating is obtained. According to the nickel-based alloy surface laser cladding coating, the surface hardness, wear resistance and service stability are greatly improved while the high-temperature strength and toughness of a nickel-based alloy matrix are kept, the service life of key parts such as a turbine disc tenon connection structure can be remarkably prolonged when the nickel-based alloy surface laser cladding coating is applied to the key parts, and the application prospect is wide.

The invention belongs to the technical field of alloy surface machining, and relates to a high-temperature alloy mother alloy bar surface machining method including shot blasting pretreatment. The machining method comprises the following steps that S1, shot blasting pretreatment is conducted, specifically, a high-temperature alloy mother alloy bar is fed into a shot blasting machine to be subjected to shot blasting treatment; and S2, finish turning machining is conducted, specifically, a lathe is used for directly conducting finish turning machining on the surface of the high-temperature alloy mother alloy bar subjected to shot blasting pretreatment. According to the method, the rough turning step in the traditional turning process is creatively replaced by shot blasting pretreatment, the shot blasting step and the finish turning step are combined, an economical surface machining route is achieved through a specific process system, and meanwhile the method has the advantages of being low in loss and high in cleanliness.

The invention relates to the technical field of alloy surface treatment, and particularly discloses a treating agent for zinc-aluminum-magnesium alloy surface corrosion prevention and a preparation method thereof.The treating agent for zinc-aluminum-magnesium alloy surface corrosion prevention is composed of a treating agent body component and a treating agent curing component, wherein the treating agent main body component comprises the following raw materials: bisphenol A epoxy resin, antioxidant toughening cellulose, a composite solvent, a flatting agent and a defoaming agent; the curing component of the treating agent comprises the following raw materials: a tackifying curing compound and a composite solvent; when acting on the surface of the zinc-aluminum-magnesium alloy, the treating agent prepared through the method has excellent adhesive force, toughness, oxidation resistance and anti-corrosion effect, the zinc-aluminum-magnesium alloy can be effectively protected, and the service life of the zinc-aluminum-magnesium alloy is long.

The invention discloses a high-conductivity phosphorus-copper alloy and a surface treatment process thereof, and relates to the technical field of copper alloy surface treatment.The surface treatment process comprises the specific steps that after the phosphorus-copper alloy is cleaned, sand blasting treatment is conducted, then a composite coating is coated, and pyrolysis annealing is conducted to obtain a middle layer; coating an epoxy composite coating on the surface of the middle layer, and curing at 40-45 DEG C for 20-24 hours to form a surface layer; wherein the composite coating is prepared from the following raw material components in parts by mass: 5 to 8 parts of phosphorus-copper doped molybdenum disulfide, 1 to 3 parts of copper powder, 0.2 to 3 parts of metal salt, 20 to 30 parts of aniline tripolymer derivative and 60 to 80 parts of N, N-dimethylformamide; the epoxy composite coating comprises the following raw material components in parts by mass: 80-100 parts of epoxy resin, 1-3 parts of modified MXene, 1-3 parts of phosphorus-copper doped molybdenum disulfide and 60-75 parts of a curing agent.

The invention relates to a preparation method of a high-hardness composite coating on a titanium alloy surface, which comprises the following steps: pretreating a titanium alloy base material to remove a surface oxide layer to obtain the treated titanium alloy base material; prepared high-entropy alloy powder is dried and evenly laid on the surface of the treated titanium alloy base material, and the titanium alloy base material with the powder laid is obtained; performing laser cladding treatment on the titanium alloy base material subjected to powder laying in a protective gas atmosphere to obtain a high-entropy alloy strengthened coating; the particle size of the powder is controlled to be 65-90 microns. The Al powder, the Co powder, the Ni powder, the Ti powder and the B powder with the purity higher than 99.5 wt% are selected as raw materials, the high-entropy alloy powder and the high-strength titanium alloy matrix are molten on the surface of the high-strength titanium alloy through a laser high-energy heat source, the metallurgical bonding effect is achieved, high-entropy phase strengthening is achieved, grains can be fine, and the hardness and abrasion resistance of a surface coating can be improved. The surface hardness of the coating prepared by laser cladding of the high-entropy alloy powder on the surface of the titanium alloy is not lower than 677 HV, and the wear resistance is not lower than 1.128 hmm.

The invention belongs to the field of vanadium-aluminum alloy smelting. The invention discloses a preparation method of a high-density low-defect vanadium-aluminum alloy. The method comprises the following steps: crushing raw materials; drying the raw materials; aluminum is prepared according to the amount of residual aluminum in the alloy accounting for 106%-108% of the theoretical amount of aluminum participating in the oxidation-reduction reaction, and the dried raw materials are evenly mixed; the mixed materials are put into a smelting furnace, and the composite flux is flatly laid on the materials; tiling titanium powder on the composite flux; igniting the titanium powder to carry out thermit reaction on the furnace charge in the furnace; gradient extreme cooling is conducted on the alloy, and sequential solidification from bottom to top is achieved at the temperature gradient of 50-100 DEG C / h; and after solidification, disassembling the furnace, carrying out water quenching, and cooling to obtain the vanadium-aluminum alloy. According to the method, the problems of surface oxidation, internal cracking, bottom loosening and the like of the vanadium-aluminum alloy can be synchronously solved, and the compactness and quality of the vanadium-aluminum alloy are remarkably improved.

The invention discloses a preparation method of an AAO / ZnMgAl-LDHs corrosion-resistant composite coating on an aluminum alloy surface, and belongs to the technical field of aluminum alloy surface protection treatment.The preparation method comprises the steps that firstly, an aluminum alloy base material is pretreated, then sulfuric acid and tartaric acid are mixed to prepare an anodic oxidation electrolyte, the treated aluminum alloy base material is placed in the electrolyte to be subjected to an electrified reaction to form an AAO film, and then the AAO film is subjected to heat treatment; and dissolving urea, magnesium salt and zinc salt in deionized water, adjusting the pH value to prepare an LDHs prefabricated solution, placing the aluminum alloy substrate with the AAO film in the LDHs prefabricated solution for in-situ growth, and finally washing and blow-drying to obtain the AAO / ZnMgAl-LDHs composite coating. The method is simple in preparation process, easy to operate, economical, environmentally friendly and good in hole sealing effect, the prepared AAO / ZnMgAl-LDHs composite coating is uniform and compact, the corrosion resistance of the aluminum alloy can be remarkably improved, the surface protection performance of the aluminum alloy can be effectively enhanced, and reliable guarantee is provided for application of the aluminum alloy in a complex environment.

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.