741 results about "Micro arc oxidation" patented technology

The invention belongs to the technical field of metal material surface treatment, and provides a self-hole-sealing and self-healing aluminum alloy corrosion-resistant coating and a preparation method thereof. The aluminum alloy is subjected to micro-arc oxidation treatment in the phosphate electrolyte containing cerium ions, the self-hole-sealing and self-healing micro-arc oxidation coating is prepared on the surface of the aluminum alloy, and the technical problems that in the prior art, an aluminum alloy micro-arc oxidation coating is poor in hole sealing effect and complex in process are solved. The beneficial effects of providing long-term active corrosion protection for the aluminum alloy and simplifying the process are achieved.

The invention relates to the technical field of high-corrosion-resistance stainless steel pipe processing, and discloses a high-corrosion-resistance high-molybdenum stainless steel pipe processing technology based on gradient carbide design, which comprises the following steps: applying an axial gradient magnetic field in a stainless steel pipe rolling process, and combining with dynamic strain rate matching rolling to promote molybdenum atom grain boundary migration and inhibit carbide coarsening, so as to obtain a high-molybdenum-resistance stainless steel pipe. Nano carbide smaller than or equal to 50 nm is formed on the surface layer, and submicron carbide of 200-500 nm is formed on the core part; after rolling, micro-arc oxidation and phosphonic acid group silane dipping are immediately carried out to form a self-repairing passivation film; and finally, an alternating magnetic field and pulse current are adopted for cooperative annealing, and a grain boundary molybdenum-poor region and residual stress are eliminated. Through magnetic field-chemical-thermal multi-field coupling, the material has erosion corrosion resistance of a gradient carbide structure, dynamic passive film self-repairing and low-temperature high toughness, and is suitable for long-acting protection of deep sea oil and gas pipelines.

The invention belongs to the technical field of metal material surface oxidation, and particularly relates to a gradient micro-arc oxidation preparation system and method. The system comprises a pretreatment device, an electrolyte batching device and a micro-arc oxidation device, and the pretreatment device is used for removing oil stains and oxide layers on the surfaces of workpieces and mechanically polishing the surfaces of the workpieces; the electrolyte batching device is used for mixing and preparing electrolyte used for workpiece micro-arc oxidation; the micro-arc oxidation device comprises a reactor containing electrolyte, and a workpiece is subjected to micro-arc oxidation in the reactor; the pretreatment device, the electrolyte batching device and the micro-arc oxidation device are sequentially connected according to an industrial production sequence. In addition, the invention further discloses a gradient micro-arc oxidation preparation method. The uniform and smooth color gradient effect on the surface of the metal material is achieved by accurately regulating and controlling key parameters such as electrolyte components, voltage, current density, oxidation time and temperature in the oxidation process.

The invention relates to the technical field of metal material surface treatment, in particular to an antifouling and anti-drag coating for titanium alloy pipeline binding force and a preparation method and application of the antifouling and anti-drag coating. The preparation method comprises the following steps: carrying out micro-arc oxidation treatment on a titanium alloy to form a ceramic film on the surface of the titanium alloy; the titanium alloy subjected to micro-arc oxidation treatment is subjected to a hydrothermal reaction, and a nanoscale porous thorn microstructure and hydroxyl are introduced to the surface of a ceramic membrane; coating the pre-polymerization liquid on the titanium alloy subjected to hydrothermal treatment, and performing irradiation reaction under ultraviolet light to obtain first network gel; the first network gel is soaked in a beta-sodium glycerophosphate solution, and the ion-covalent double network p (SBMA-co-AAc) / CS-beta-GP DN hydrogel is formed. The stability and durability of the coating prepared by the preparation method provided by the invention are improved, and the coating has long-term stable anti-fouling performance, is strongly combined with a titanium alloy substrate, and has excellent anti-fouling effect and anti-drag effect when being applied to the titanium alloy substrate.

The invention discloses a production process of a high-strength anti-corrosion power transmission pole cross arm. The production process comprises the following steps that 1, an anti-SCC aluminum alloy is selected; a trace amount of Sc is added to refine grains, so that the corrosion resistance is improved; cold machining is avoided, and a warm forming process is adopted; 2, aluminum alloy ingot smelting and hot extrusion forming are carried out; 3, T6 solid solution treatment is carried out to improve the strength; 4, the five-axis CNC machining center conducts structural topology optimization cutting; the surface roughness Ra of a key bearing part is less than or equal to 0.8 mu m; an ultrasonic-assisted drilling technology is adopted; step 5, micro-arc oxidation; and step 6, ultrasonic flaw detection and infrared thermal imaging. The 5083-H116 aluminum alloy is combined with Sc microalloying, precision machining and micro-arc oxidation technologies, so that the stress corrosion resistance is improved by 3 times, the fatigue life is prolonged by 2-3 times while the tensile strength of the power transmission pole cross arm is kept to be larger than or equal to 350 MPa, 5000-hour salt mist protection and 30-year maintenance-free are achieved, and the service life of the power transmission pole cross arm is prolonged. The problems of corrosion cracking, short fatigue life and insufficient durability of a traditional product in a harsh environment are comprehensively solved.

The invention discloses a biomedical magnesium alloy and a preparation method thereof, and belongs to the technical field of magnesium alloy materials. The biomedical magnesium alloy comprises a magnesium alloy matrix, a micro-arc oxidation film layer is arranged on the surface of the magnesium alloy matrix, and a PLGA-HA composite coating is arranged on the surface of the micro-arc oxidation film layer. The micro-arc oxidation film serves as a magnesium alloy surface modification base layer, provides a good adhesion interface for the composite coating and enhances the corrosion resistance of a base body. By introducing the PLGA-HA composite coating on the micro-arc oxidation film on the surface of the magnesium alloy, the PLGA coats and stabilizes HA particles, so that the HA particles are distributed more uniformly, meanwhile, the bonding strength of the HA and the micro-arc oxidation film is improved, the stripping phenomenon of the coating is reduced, and the long-term stability of the coating is ensured. In addition, the composite coating further fills up pores and cracks of the micro-arc oxidation film, and the overall compactness and corrosion resistance are remarkably improved, so that the degradation rate of the magnesium alloy is effectively delayed.

The invention provides a preparation method and application of a corrosion-resistant micro-arc oxidation film layer. The method comprises the following steps: pretreating valve metal and / or an alloy matrix thereof; and the pretreated valve metal and / or an alloy matrix of the valve metal are / is immersed in electrolyte of a bipolar superaudio frequency pulse micro-arc oxidation system, micro-arc oxidation parameters are set as follows: the voltage ranges from-50 V to 600 V, the power output pulse frequency ranges from 1 kHz to 150 kHz, the duty ratio ranges from 0.1 to 0.5, micro-arc oxidation is conducted for a preset duration, and the metal matrix with the corrosion-resistant micro-arc oxidation film layer is obtained. According to the method, the high-corrosion-resistance micro-arc oxidation film layer can be obtained.

The invention belongs to the technical field of biological material surface modification, and discloses a medical titanium alloy surface bionic multifunctional composite coating and a preparation method thereof. According to the method, the medical titanium alloy is sequentially subjected to micro-arc oxidation and anodic oxidation, and then the bionic multifunctional composite coating on the surface of the medical titanium alloy is prepared. The purpose of micro-arc oxidation is to prepare a micron porous coating on the surface of the medical titanium alloy. According to anodic oxidation, a series of nano-coatings are synthesized on the surface of the micro-arc oxidation coating, the nano-coatings can be composed of discontinuous cauliflower-shaped nano-particles or can be of a continuous film-forming cauliflower-shaped structure, and the thickness of the nano-coatings can be from the nanometer level to the micrometer level. According to the coating, the biological function is further improved through the nano coating while the mechanical anchoring effect of the micron porous structure on new bone tissue is maintained. Even if the coating is damaged by external force, the high binding force of the coating does not cause the failure of the coating, and the coating also has good wear resistance and corrosion resistance.

The invention provides a biological magnesium alloy micro-arc oxidation coating supercritical hole sealing method based on a thermodynamic sedimentary phase diagram, which comprises the following steps: establishing deposition-dissolution balance of metal ion phosphide and hydroxide of a phosphate conversion film in a supercritical carbon dioxide environment at different pH values to obtain the thermodynamic sedimentary phase diagram; selecting a NaH2PO4 solution according to a thermodynamic sedimentary phase diagram, and adding NaHCO3 to obtain a hole sealing solution; the hole sealing solution is injected into a reaction kettle to be heated, and then a refrigerator is started to convert generated carbon dioxide gas into supercritical carbon dioxide; and the biological magnesium alloy subjected to micro-arc oxidation is placed in the hole sealing solution in the reaction kettle to be pressurized, and holes of the micro-arc oxidation coating on the surface of the biological magnesium alloy are sealed. The invention provides a supercritical hole sealing method for a biological magnesium alloy micro-arc oxidation coating based on a thermodynamic sedimentary phase diagram. And the hole sealing effect is good.

The invention discloses an anode material for adipic acid monoester electrolysis and a preparation method of the anode material, the electrode solves the key problems that a platinum layer is easy to fall off, the catalytic activity is low, the organic matter poisoning resistance is poor and the like of a traditional titanium platinum-plated electrode through multi-scale interface strengthening and nano structure regulation and control; the preparation method comprises the following core steps: constructing a porous ZrO2-TiO2 composite oxide layer on the surface of a titanium substrate by adopting a micro-arc oxidation-hydrothermal composite process, and generating platinum nanoparticles in situ to pre-fill pores, so that the anchoring effect of a platinum layer is remarkably enhanced; depositing a platinum / carbon nano tube (Pt / CNT) composite catalyst layer on the surface of the oxide layer through a pulse-ultrasonic synergistic electroplating technology, wherein the carbon nano tube is used as a conductive framework to inhibit platinum agglomeration; through vacuum annealing and electrochemical activation treatment, the interface bonding force and active site exposure are further optimized; the electrode shows excellent performance in an adipic acid monoester electrolysis system, and efficient electrocatalytic conversion from adipic acid monomethyl ester to dimethyl sebacate is achieved.

The invention discloses a coating with in-situ plugging and active protection functions as well as a preparation method and application thereof, and belongs to the technical field of metal material surface treatment. An innovative electrolyte design scheme is provided, the commercial 5083 aluminum alloy is subjected to micro-arc oxidation in a phosphate system containing specific cerium salt and a complexing agent, film layer growth and in-situ chemical blocking of micropores are completed in one step, the process is simple, and the obtained coating has excellent blocking firmness and corrosion resistance, has an active protection function and is suitable for large-scale industrial production. And a new solution is provided for improving the durability of the 5083 aluminum alloy in a harsh marine environment.

The invention discloses an integrated preparation method of a large-thickness high-density electrical insulation-corrosion-resistant ceramic coating on the surface of a heat dissipation substrate for a high-power device, and relates to the technical field of surface treatment of aluminum alloys and composite materials thereof. The method comprises the following steps: placing a pretreated substrate as an anode and a stainless steel plate as a cathode in a basic arc suppression type electrolyte, and performing low-temperature soft plasma electrolytic oxidation on the surface of the pretreated substrate by using an asymmetric bipolar pulse micro-arc oxidation technology to grow a large-thickness high-density ceramic layer in situ; specifically, low-temperature soft spark discharge is induced by inserting additional negative pulse voltage, the plasma temperature and energy are stabilized, spark discharge is uniform, and the density is increased by an order of magnitude, so that continuous bombardment with no damage to the surface flatness as the plasma intensity upper limit is carried out on a passive film on the surface of a substrate; and the defects such as pores and cracks are continuously healed and repaired, and the densification of the coating is promoted, so that the aluminum oxide coating with large thickness, high density, high electrical insulation and corrosion resistance is obtained.

The invention relates to the technical field of metal-based composite materials, and discloses a preparation method of a silicon carbide reinforced aluminum-based composite material for electronic packaging, the method that pre-oxidation is conducted on the surfaces of silicon carbide particles first and then vacuum micro-evaporation titanium plating is conducted is adopted, the wettability with an Al matrix is obviously improved, generation of an interface reaction brittle product Al4C3 is inhibited, and the performance of the silicon carbide reinforced aluminum-based composite material is improved. Defects such as gaps in the composite material are reduced, and the mechanical property of the composite material is improved; the silicon carbide reinforced aluminum-based composite material is prepared by adopting a non-pressure infiltration method, so that the production time is obviously shortened, infiltration can be successful by taking a small amount of time, and the process is stable; the interface phase TiC / Ti5Si3-Al coating not only improves the electrical conductivity and thermal conductivity of the silicon carbide powder, but also enhances the adhesive force of the silicon carbide powder and an aluminum base; al2O3 is gradually adsorbed and deposited on the surface of the material by adopting a micro-arc oxidation process, so that the corrosion resistance of the aluminum silicon carbide composite material is enhanced, and the requirements of a contemporary packaging material on high heat dissipation and corrosion resistance can be met.

The invention relates to the technical field of lamps, in particular to a plating forming process of a lamp. The problems that the interface bonding force of the coating and the matrix is insufficient and the corrosion resistance of the coating is poor are solved. According to the method, micro-arc oxidation is carried out in the pretreatment stage, a compact Al-Si-O ceramic layer is generated on the surface of a high-aluminum matrix in situ, and in combination with deep diffusion of plasma siliconizing, a transition area with gradient Si distribution is constructed; the pitting corrosion resistance of the coating is optimized through the component gradient design of the inner-layer coating, the middle-layer coating and the outer-layer coating; the surface of the coating lamp is subjected to checkerboard scanning by using short pulse laser, so that the porosity and microdefects of the surface of the coating are improved, and the corrosion resistance of the coating is enhanced; a uniform oxynitride passivation film is generated on the surface of the coating in situ through low-temperature plasma post-oxidation-nitridation treatment, the defect that a film layer is easy to strip in a traditional passivation process is avoided, and the corrosion resistance of the material in long-term service can be stably maintained.

The invention relates to the technical field of coating materials, and discloses a pure titanium micro-arc oxidation coating for a vacuum cup and a preparation method thereof.The preparation method comprises the following steps that surface pretreatment is conducted, specifically, a pure titanium vacuum cup inner container workpiece is sequentially subjected to degreasing, acid pickling and ultrasonic cleaning; preparing an electrolyte, namely adding 15-25 parts by weight of a silicon-containing compound, 5-12 parts by weight of metal salt, 3-8 parts by weight of an antibacterial agent and 1-5 parts by weight of a stabilizer into deionized water, and controlling the pH value to be 8.5-10.5; and performing micro-arc oxidation treatment. According to the invention, a silane compound in the micro-arc oxidation electrolyte contains a high-activity silanol group which is subjected to condensation reaction with titanium hydroxyl on the surface of a pure titanium substrate under the action of an electric field to form stable covalent bonding, so that the bonding strength of the coating and the substrate is enhanced; metal ions generated by metal salt electrolysis are co-deposited with titanium ions through plasma discharge, a composite oxide structure is constructed, and micro defects on the surface of a titanium substrate are sealed.

The invention relates to the technical field of aluminum alloy heat treatment, and discloses a high-power tooth radiator aluminum alloy strengthening and toughening heat treatment method. Gradient temperature control solution treatment including at least two different temperature stages; step 2; carrying out electromagnetic auxiliary shape correction treatment, and applying an alternating magnetic field in the cooling process; step 3; the two-stage aging treatment comprises high-temperature first-stage aging and low-temperature second-stage aging; step 4; carrying out pulse type aging strengthening by adopting a periodic temperature fluctuation mode; step 5; and performing micro-arc oxidation surface treatment to generate an aluminum oxide layer in the electrolyte. Gradient temperature control solution treatment is adopted, a beta phase is fully dissolved, abnormal growth of crystal grains is inhibited, meanwhile, uniform nucleation of a GP region and dispersed distribution of a theta'phase are promoted through two-stage aging treatment, the strength and toughness of the alloy are improved, in addition, electromagnetic auxiliary shape correction and a composite residual stress elimination technology are combined, thermal stress deformation is effectively inhibited, residual stress is eliminated, and the performance of the alloy is improved. The size stability and the fatigue life are improved.

The preparation method of the aluminum oxide hydrogen-resistant coating on the zirconium hydride surface disclosed by the embodiment of the invention comprises the following steps: S1, plating aluminum on the surface of a zirconium hydride matrix in a magnetron sputtering manner, and forming an aluminum film on the surface of the zirconium hydride matrix; and S2, the aluminum film formed on the surface of the zirconium hydride matrix is subjected to micro-arc oxidation to obtain aluminum oxide, and the aluminum oxide hydrogen-resistant coating is obtained. Wherein an aluminum oxide film layer formed on the surface of zirconium hydride is tightly combined with a zirconium hydride matrix, and the thickness of the film layer is 5-80 microns; the aluminum oxide film layer is composed of an inner compact layer with a non-porous structure and an outer loose layer with a closed pore structure, the thickness of the compact layer is 2-15 microns, and the compact layer has a good hydrogen permeation resistance effect; the aluminum oxide film layer on the surface of zirconium hydride can serve as an aluminum oxide hydrogen-resistant coating, the hydrogen-resistant capacity of the zirconium hydride moderator is improved, and the service life of the zirconium hydride moderator is prolonged.

The invention belongs to the technical field of magnesium-zinc magnesium alloy surface treatment, and particularly relates to a method for in-situ growth of different blue ceramic film layers on the surface of a magnesium-zinc magnesium alloy. Comprising the following steps that the surface of a magnesium-zinc magnesium alloy sample is polished and cleaned, and then the surface of the sample is sequentially subjected to primary alkali washing, primary water washing, primary acid pickling, secondary water washing, secondary acid pickling, tertiary water washing and secondary alkali washing, so that the pretreated magnesium alloy is obtained; the pretreated magnesium alloy is placed in electrolyte for micro-arc oxidation treatment, and a blue ceramic film layer is generated on the surface of the magnesium alloy in situ; the electrolyte is formed by adding potassium fluotitanate and cobaltous sulfate into a silicate and phosphate composite electrolyte system; or the electrolyte is obtained by adding potassium fluotitanate into a phosphate electrolyte system. Different blue ceramic film layers are prepared, the ornamental value of the magnesium-zinc magnesium alloy component can be improved, and the visual effect is improved.

The invention discloses a titanium-based implant with antibacterial and osteogenesis-promoting properties as well as a preparation method and application thereof, and belongs to the technical field of crossing of biomedical materials and biomedicine. The selective laser melting porous titanium alloy is used as a matrix, micro-arc oxidation and hydro-thermal treatment are utilized, and the multifunctional composite coating with the antibacterial function and the osteogenesis promoting function is constructed on the surface of the selective laser melting porous titanium alloy; the microstructure and the biological performance of the coating are regulated and controlled by doping functional elements, so that the antibacterial performance and the osteogenesis promoting performance of the coating are optimized.

The invention discloses a high-temperature-resistant and corrosion-resistant aluminum alloy material and a preparation process thereof, and relates to the technical field of aluminum alloy materials. The high-temperature-resistant and corrosion-resistant aluminum alloy material is prepared by carrying out micro-arc oxidation treatment on aluminum alloy, carrying out plasma spraying on a corrosion-resistant spray coating and carrying out heat treatment. The aluminum alloy comprises the following raw material components in percentage by weight: 0.05%-0.15% of silicon, 0.1%-0.2% of iron, 1.2%-1.5% of copper, 0.7%-0.9% of manganese, 2.5%-3.8% of magnesium, 10.2%-12.4% of zinc, 0.02%-0.04% of titanium, 0.08%-0.15% of zirconium, 0.2%-0.4% of scandium, 0.5%-0.8% of silicon nitride whiskers, 0.5%-1% of an aluminum-coated graphene material and the balance of aluminum.

The invention belongs to the technical field of metal material surface modification, and particularly relates to a magnesium alloy surface conductive corrosion-resistant coating and a preparation method, the conductive corrosion-resistant coating comprises a three-layer structure, the total coating thickness is 33-50 microns, the bottom coating is a low-porosity MAO coating prepared through a micro-arc oxidation method, and the thickness is 20-35 microns; the middle coating is a conductive nano-particle layer prepared by adopting a negative pressure mode; and the top coating is a zinc aluminum oxide conductive layer prepared by adopting a vapor-phase hydrothermal deposition method, and the thickness of the top coating is 13-15 microns. In addition, the invention provides the modified magnesium alloy with the conductive corrosion-resistant coating prepared on the surface, the self-corrosion current density of the modified magnesium alloy is 0.18-1.8 * 10 <-7 > A / cm < 2 >, and the volume resistivity of the modified magnesium alloy is 1.30-5.21 * 10 < 4 > omega.m.

The invention discloses a high-temperature-corrosion-resistant stainless steel gas distribution disc and a preparation method thereof, and relates to the technical field of stainless steel machining, stainless steel is subjected to micro-arc oxidation treatment, the high temperature resistance and wear resistance of the surface of the stainless steel are improved, but the corrosion resistance of the stainless steel subjected to micropore treatment needs to be improved. Stainless steel subjected to micro-arc oxidation treatment is subjected to titanium dioxide layer plating treatment, micro-arc oxidation holes provide additional anchoring points, titanium dioxide layer plating treatment is carried out on the basis, the corrosion resistance of the stainless steel is improved, micro-arc oxidation treatment is firstly carried out on the surface of the stainless steel, then titanium dioxide is plated on the surface of the stainless steel, and the corrosion resistance of the stainless steel is improved. And the binding force between the titanium dioxide layer and the stainless steel substrate can be obviously improved. The graphene oxide-titanium dioxide composite sol is added into the electroplating solution, invasion of corrosive media is effectively blocked, the diffusion path of the corrosive media is prolonged through the graphene sheet layer, and the corrosion resistance of the stainless steel is further improved.

Disclosed are a corrosion-resistant film for a magnesium alloy wheel and a preparation method thereof, The corrosion-resistant film for a magnesium alloy wheel includes: a micro-arc oxidation (MAO) coating, a chemically blocked coating, a physical vapor deposition (PVD) high-density inorganic hybrid coating, a high oxidation-resistant powder coating which are sequentially stacked from inside to outside by using the magnesium alloy wheel as a substrate. In the present disclosure, based on a micro-arc oxidation technology, zirconium, titanium, an iron salt, nano silicon, polymer resin are added into an electrolytic solution, and under a constant voltage mode of an adjustable power supply, the MAO coating is generated on the surface of the magnesium alloy wheel, followed by chemical blocking; the PVD high-density inorganic hybrid coating is obtained by coating on the chemically blocked coating, physical blocking is performed; the high oxidation-resistant powder coating is spray-coated on the PVD high-density inorganic hybrid coating.

According to the manufacturing method, through a Roll to Roll continuous production mode, traditional 19 procedures are reduced to 12 procedures, the production speed is increased to 5 m / min, the dielectric constant of a composite PI film doped with nanometer aluminum oxide is smaller than or equal to 3.2 and is reduced by 15% compared with that of a traditional PI film, a micro-arc oxidation insulating layer of copper / magnesium alloy foil is combined, the signal loss of the antenna in the frequency band of 28-300 GHz is reduced by 30%, and the antenna performance is improved. The sheet resistance of the graphene / silver nanowire composite conductive adhesive is smaller than or equal to 0.1 omega / sq, the bending life is larger than or equal to 100,000 times, the performance is improved by 10 times compared with that of traditional silver paste, the long-term dynamic use requirement of wearable equipment is met, no chemical etching liquid is used in the whole process, waste is subjected to magnetic separation and low-temperature pyrolysis, waste discharge is reduced by 90% compared with a traditional process, and the graphene / silver nanowire composite conductive adhesive is environmentally friendly. The carbon-based particles generated through pyrolysis meet the RoHS standard and can be directly used for 3D printing consumables, the antenna produced through the method can adapt to the leading-edge fields of 6G base stations, flexible intelligent watches, implantable medical sensors and the like, and the technology of the Internet of Things and high-frequency communication is promoted.

The invention relates to the field of preparation of lubricating materials, in particular to a preparation method of composite phase change lubricating gel based on temperature-friction force synergistic response. The lubricating gel adopts a sandwich layered structure; the bottom layer is a porous ceramic layer formed by micro-arc oxidation, is filled with a disulfide bond dynamic network polymer and is anchored on a metal substrate; the middle layer comprises a microencapsulated phase change material which is dispersed in a polyurethane network containing dynamic disulfide bonds and is wetted with ionic liquid; the surface layer is an epoxy resin coating rich in boron nitride nanosheets, and a rapid heat conduction channel is constructed. Compared with the prior art, the lubricating state can be automatically adjusted in the friction process without external energy input, and the method has the advantages of being sensitive in multi-field coupling response, capable of achieving automatic antifriction protection, high in extreme working condition adaptability and the like.

Methods for producing durable oxide coatings on various substrates are provided. The method involves depositing an oxidizable metal layer, such as zirconium, aluminum, titanium, magnesium, or niobium, onto a substrate using physical vapor deposition techniques, including sputtering, evaporation, or cathodic arc deposition. The oxidizable metal layer is subsequently treated using anodization or micro-arc oxidation (MAO) to convert at least a portion of the layer into a robust oxide coating. The MAO process employs high voltages and current densities in an electrolytic bath containing water, salts, and additives to enhance surface properties. The resulting oxide layer provides exceptional hardness, corrosion resistance, thermal stability, and aesthetic finishes, including a black appearance. The method is compatible with diverse substrates, including metals, alloys, and plastics, enabling applications in aerospace, automotive, consumer electronics, and decorative industries. This approach overcomes limitations of traditional coatings by delivering tailored, high-performance surfaces.

The invention discloses an anti-corrosion magnesium alloy and a preparation method and a micro-arc oxidation treatment process thereof, relates to the technical field of magnesium alloys, and solves the problem of poor corrosion resistance of magnesium alloys in the prior art. The anti-corrosion magnesium alloy prepared by the method comprises the following chemical components in percentage by mass: 4-8 wt% of aluminum, 2-5 wt% of lanthanum, 1-3 wt% of samarium, 0.5-1.0 wt% of gadolinium, 0.3-0.6 wt% of yttrium, 0.2-0.5 wt% of manganese, magnesium and inevitable impurities, wherein the total mass fraction of the inevitable impurities is less than 0.03%. The anti-corrosion magnesium alloy is prepared by introducing rare earth elements (lanthanum, samarium, gadolinium and yttrium), the micro-arc oxidation ceramic film layer is prepared on the surface of the anti-corrosion magnesium alloy by adopting a low-voltage, low-duty-ratio and low-concentration electrolyte micro-arc oxidation treatment process, the electrochemical corrosion reaction is effectively inhibited, the corrosion resistance of the alloy is improved, the cost is low, and the application range is wide. Good industrial application prospects are realized.

The invention relates to a multifunctional magnesium alloy coating with high biocompatibility and a preparation method and application thereof. Comprising the following steps: (1) carrying out surface treatment on a magnesium alloy substrate; (2) micro-arc oxidation treatment; (3) after preparing a coating solution, carrying out double-sided ultrasonic atomization spraying; and (4) drying, soaking and cleaning. According to the preparation method, a micro-arc oxidation treatment technology and a double-sided ultrasonic atomization spraying technology are combined for the first time, pores and cracks of the MAO coating serve as binding sites, effective loads are provided for the silk fibroin / nano-hydroxyapatite particle coating, the MAO coating and the SF / nHAp coating are fully combined, and the composite coating is prepared. According to the coating, the MAO coating and the SF / nHAp coating are combined for the first time, the defect of rapid degradation when the magnesium alloy serves as an in-vivo implant is effectively overcome, the corrosion resistance of the magnesium alloy is remarkably improved, the release rate of hydrogen after implantation is reduced, and rising of the pH value around the implant is slowed down.

The invention discloses a preparation process of a high-strength corrosion-resistant stainless steel fastener. The preparation process comprises the steps of material modification, warm upsetting forming, stabilizing treatment, cryogenic strengthening, gradient aging, surface treatment, post-treatment and the like. According to the process, the alloy component proportion is optimized, a thermal mechanical treatment technology of warm upsetting forming, subzero treatment and gradient aging is combined, a nano-composite coating and micro-arc oxidation sealing process is innovatively introduced, and the process comprises vacuum melting and controlled rolling of customized high-nitrogen stainless steel wires, deformation-induced martensite regulation in warm upsetting forming, low-temperature hot rolling, high-temperature hot rolling, high-temperature hot rolling, high-temperature hot rolling, high-temperature hot rolling and high-temperature hot rolling. The tensile strength and the salt spray corrosion resistance of the fastener are remarkably improved through deep cooling-medium temperature aging synergistic strengthening, double-layer nano TiN / CrN composite coating deposition and micro-arc oxidation micropore sealing treatment, the problem that a traditional stainless steel fastener is insufficient in strength and low in stress corrosion sensitivity is solved through the technology, and the technology is particularly suitable for the extreme environments such as aerospace and ocean engineering.

The invention discloses a method for preparing a non-polymer coating of a pure magnesium intravascular stent, and relates to the technical field of medical instruments, and the method comprises the following steps: pretreatment: immersing the pure magnesium intravascular stent into a diluted hydrochloric acid solution for ultrasonic cleaning, removing a surface oxidation film and impurities, then washing the pure magnesium intravascular stent with deionized water until the pure magnesium intravascular stent is neutral, and drying the pure magnesium intravascular stent for later use; micro-arc oxidation: taking the pretreated bracket as an anode, taking a stainless steel plate as a cathode, putting the bracket and the stainless steel plate in electrolyte, applying pulse voltage for treatment, and generating a ceramic oxide layer with the thickness of 5-20 microns on the surface of the bracket; and bioactive coating: immersing the stent subjected to micro-arc oxidation into the suspension, and depositing by adopting an electrophoretic deposition method to form a hydroxyapatite coating with the thickness of 1-5 microns. According to the non-polymer coating method for the pure magnesium intravascular stent, no polymer is used in the whole coating process, inflammatory reaction possibly caused by the polymer and degradation products of the polymer is avoided, and the biological safety of the stent is improved.