104 results about "Pitting corrosion" patented technology

The invention relates to the technical field of alloy processing, and discloses a high-performance corrosion-resistant nickel-based alloy plate and a preparation method thereof, and the method comprises the following steps: raw material preparation, smelting treatment, casting treatment, hot rolling treatment, solution treatment, aging treatment and surface passivation treatment. According to the invention, when a composite acid system is adopted for passivation treatment, the concentration of chromium / molybdenum atoms in a passivation film is optimized and balanced due to the specific ratio of nitric acid to chromic acid, a chromium oxide provides a compact passivation barrier, and a molybdenum oxide endows the film layer with a self-repairing characteristic to synergistically inhibit pitting nucleation; meanwhile, nano titanium dioxide particles pretreated by silane are embedded into the passivation film in situ under the action of ultrasonic oscillation, organic pollutants adsorbed on a film layer can be decomposed by the photocatalytic characteristic of the nano titanium dioxide particles, the local corrosion effect of a battery caused by dirt coverage is avoided, and the performance of the battery is improved through double upgrading of components and the structure of the passivation film. And the alloy plate has excellent pitting corrosion resistance and fouling resistance in a chloride ion-containing medium.

The invention discloses a high-robustness multi-scale defect detection method for a metal matrix surface, and relates to the technical field of machine vision and surface defect detection. In order to solve the problems of large scale difference of metal matrix surface defects, strong background noise and easy missing detection of tiny targets in a complex service environment, an EMA-YOLO deep network proposed by the invention is characterized in that an efficient multi-scale attention (EMA) mechanism is introduced into a YOLOv8 backbone network, and the influence of background interferences such as surface water stains and oil stains on defect identification is inhibited through a cross-space learning strategy; a P2 layer-based high-resolution tiny target detection head is constructed, and shallow geometric details are reserved to accurately capture early pitting corrosion and microcracks; a Shape-IoU loss function is introduced, and through shape perception and adaptive weight adjustment, the positioning precision of cracks and irregular spalling defects with extreme length-width ratios is optimized. The EMA-YOLO deep network provided by the invention can effectively improve the accuracy, stability and robustness of multi-scale defect detection under a complex texture background.

The invention discloses an aluminum pipe, a heat exchanger and application thereof, and belongs to the technical field of heat exchange materials. The aluminum pipe comprises an aluminum pipe base material layer and a zinc impregnation layer arranged on the surface of the aluminum pipe base material layer. The zinc impregnation layer has a zinc concentration gradient which is gradually reduced from outside to inside; the maximum zinc concentration of the zinc impregnation layer is 0.01 to 10 weight percent; the thickness of the zinc impregnation layer is larger than 0 and smaller than or equal to 400 micrometers. The zinc impregnation layer is formed on the surface of the aluminum pipe base material layer, corrosion can be limited from expanding to the inner layer, longitudinal expansion of corrosion is avoided, pitting corrosion is inhibited, the zinc content distribution of the zinc impregnation layer at different zinc impregnation depths can be controlled by controlling the maximum zinc concentration and thickness of the zinc impregnation layer, and the corrosion resistance of the aluminum pipe is improved. The zinc impregnation layer has a good anodic protection effect on the aluminum pipe, pitting corrosion extension is effectively inhibited, the corrosion resistance of the aluminum pipe is improved, and the service life of the aluminum pipe is prolonged.

The invention relates to the technical field of corrosion monitoring, and provides a titanium equipment pitting early warning method and system based on electrochemical impedance spectroscopy analysis, and the method comprises the steps: collecting an electrochemical impedance spectroscopy original response signal, and carrying out the spectroscopic normalization of the electrochemical impedance spectroscopy original response signal to obtain an effective characteristic segment; performing decoupling analysis on the real part and the imaginary part of the effective feature segment to obtain decoupling component data, and performing phase correction on the decoupling component data to obtain a calibrated component; constructing an impedance characteristic spectrum by taking the capacitive reactance characteristic in the calibrated component as a center and the impedance characteristic in the calibrated component as an edge; performing precursor targeted identification on the impedance characteristic spectrum to obtain pitting precursor characteristics; performing development gradient deduction on the pitting precursor features to obtain pitting evolution data; performing hierarchy judgment on the pitting evolution data to obtain a risk hierarchy, and generating early warning information according to the risk hierarchy; according to the method, the pitting early warning efficiency of the titanium equipment can be improved.

According to the anodic oxidation technology suitable for the 6061 aluminum alloy, multi-component silica sol is adopted for conducting room-temperature dipping hole sealing and low-temperature curing on a 6061 aluminum alloy anodic oxidation film, and technology energy consumption and equipment requirements are reduced. The dense silicon network seals the membrane holes, prolongs the diffusion path of a corrosive medium and prevents the corrosive medium from invading the substrate, thereby greatly improving the corrosion resistance of the membrane layer and inhibiting pitting corrosion.

A multi-element microcouple adaptive selective corrosion dynamic expansion simulation method, belonging to the field of electro-corrosion simulation technology, is disclosed. The method includes: constructing a geometric model of compound particles and meshing the model; constructing the compound particle transport control equations and establishing the coupling relationship between potential, particle concentration, current density, boundary coverage, and reaction rate; adaptively selecting the anode and cathode among the multi-element microcouples of the compound particles and performing fixed-value processing on the geometric model; setting boundary conditions and initial values, including setting insulating boundaries, electrode surface boundaries, and initial particle concentrations; re-meshing the mesh, calculating the movement velocity of the corrosion interface, and constraining and controlling boundaries that do not corrode or undergo geometric deformation to complete the construction of the finite element model; solving the finite element model and outputting relevant physicochemical parameters during the corrosion process. This application clarifies the driving mechanism of pitting corrosion under open-circuit conditions and the existence state of corrosion products.

The invention discloses an anti-corrosion composite coating for an ammonia gas engine, relates to an anti-corrosion technology for an ammonia gas fusion engine, and solves the technical problem that the reliability, durability and commercialization process of an ammonia fuel engine are restricted by the existing engine material system and protection technology. The composite coating comprises a base material arranged on the surface of the ammonia gas engine component; the base material layer is adjacent to the base material layer, is arranged on the surface of the base material and is used for resisting ammonia-alkali corrosion; the middle transition layer is arranged on the surface of the adjacent base material layer and is used for component gradient transition and stress relief; and the outermost surface layer is arranged on the surface of the middle transition layer and is used for resisting acid corrosion and pitting corrosion. The invention further discloses an intelligent corrosion prevention system and method for the ammonia gas engine. The invention solves the problem of limited protection performance of the traditional single coating.

The invention relates to a method and a product for regenerating and repairing duplex stainless steel, the duplex stainless steel is used for a nuclear-grade main pipeline, pulse current with optimized parameters is adopted to treat the duplex stainless steel in the nuclear-grade main pipeline with pitting corrosion or intergranular corrosion generated in the service process, the corrosion resistance of the duplex stainless steel is recovered, and dynamic self-repairing of a passive film is achieved. According to the method, pulse current in-situ / near-in-situ treatment is carried out on the duplex stainless steel for the nuclear-grade main pipeline under the electric-thermal coupling condition, components do not need to be disassembled or large-volume furnace heating does not need to be carried out, and the structure and geometric accuracy of a casting are not changed; by selecting matched parameters such as pulse frequency, pulse width, current density and treatment time, an amplitude-modulated decomposed structure in a ferrite phase and a phase interface precipitated phase are promoted to be re-dissolved, the formation dynamics and stability of a passive film are improved, and the corrosion resistance and toughness of an aged material are recovered or close to an unaged state.

The invention discloses a welding and heat treatment method for improving corrosion resistance of a 2205 duplex stainless steel welded joint, and belongs to the field of heat treatment of metal materials. The problem that in the prior art, a 2205 duplex stainless steel welded joint is insufficient in corrosion resistance in a severe marine corrosion environment is solved. The method comprises the steps that the surface of a to-be-welded 2205 duplex stainless steel plate is pretreated, and assembling is conducted in a butt joint mode; then, under the protection of inert gas, direct current positive connection and pulsed argon arc welding methods are adopted for welding; and then carrying out heat treatment, and cooling in an air cooling manner. According to the method, the microstructure of the joint can be effectively optimized, so that the pitting corrosion resistance, the stress corrosion resistance and the like of the joint are remarkably improved. The method disclosed by the invention is particularly suitable for a welded component serving in a marine harsh corrosion environment.

The invention relates to the technical field of coating material preparation, in particular to a microbead modified corrosion-resistant dry plating metal powder coating material and a preparation method thereof, and the material comprises carboxyl polyester resin, epoxy resin, a curing accelerator, a flatting agent, a degassing agent, a pigment filler, brush polymer modified microbeads, a metal pigment, a dry plating binder and a charge adjusting aid. According to the powder coating material, the corrosion resistance and durability are remarkably improved while the metal appearance and the construction stability are maintained, the coating film interface bonding is high, pore channels are few, and foaming, pitting corrosion and corrosion medium permeation along the interface in the salt mist environment can be effectively inhibited; after scratches or micro-cracks are formed, the coating film has micro-crack sealing / self-passivation capability, the corrosion rate extending along the scratches can be reduced, and the service life can be prolonged; and meanwhile, the powder is electrified uniformly, the powdering rate is high, the film thickness distribution is more uniform, the metal dry plating effect is stable, the color difference fluctuation in recycling is small, and the powder coating is suitable for metal base material protective coating with the requirements for appearance and corrosion resistance at the same time.

The invention discloses a bronze ware model casting parting design method and system based on Boolean modeling, particularly relates to the field of digital model casting modeling and simulation verification, is used for solving the problems of parting cutting error accumulation and model block seepage stability loss under the complex morphology of a bronze ware, and provides a model casting parting design method and system based on Boolean modeling by constructing a morphology noise mapping and semantic slicing linkage mechanism. Early recognition of pitting corrosion and back-off areas is achieved, Boolean segmentation is driven through curvature constraint, and a flexible buffer surface is introduced into a danger area to achieve transition; a cross-domain parameter evaluation and adjustment mechanism is formed in combination with multi-scale displacement optimization and physical simulation feedback, high-response parameter write-back is realized through local disturbance search, a full-link linkage path from modeling to casting is constructed, and parting integrity and model block stability are improved.

This invention relates to a high-temperature corrosion-resistant Fe-Cr-Mo-Ni alloy, its preparation method, and its applications. The alloy composition is 37%–40% Ni, 19%–29% Cr, and 5%–10.27% Mo, with the balance being Fe and trace impurities. X-ray diffraction of the alloy reveals a single-phase face-centered cubic structure. After holding at 800℃ for 400 hours, the area fraction of the σ phase in the microstructure does not exceed 5%. The breakdown potential in 3.5% NaCl solution is as high as 1.029 V, and its pitting corrosion resistance is superior to commercial 904L stainless steel. This alloy shows great promise for industrial application in the preparation of high-temperature resistant structural components operating under high corrosion conditions above 400–900℃, especially in service environments containing chloride ions, fluoride ions, or sulfides.

Provided is a stainless steel material having excellent general corrosion resistance and pitting corrosion resistance even in a supercritical corrosive environment. A stainless steel material according to the present disclosure has a chemical composition described in the description, results in Fn1 being at least 32.0 as defined by formula (1), and has a microstructure including, in volume fraction, 35-70% of ferrite and 0-15% of residual austenite, the balance being tempered martensite. In the stainless steel material, the total number density of coarse Mn sulfides having an equivalent circle diameter of at least 1.0 µm and coarse Ca sulfides having an equivalent circle diameter of at least 2.0 µm is 0.60 particles / mm2 or less. The total number density NDF particles / mm2 of coarse Mn sulfides and coarse Ca sulfides in ferrite and the total number density NDO particles / mm2 of coarse Mn sulfides and coarse Ca sulfides in phases other than ferrite satisfy formula (2).　(1): Fn1=Cr+3.3(Mo+0.5W)+16N+2Ni+Cu+2Co+10Sn (2): NDO / NDF<0.60

This invention discloses a metal flux-cored welding wire for wind turbines, comprising flux powder and a welding sheath. The flux powder is composed of the following components: Ni: 58%-80%, Cr: 10%-16%, Mo: 4%-12%, Nb: 1%-3%, Fe: 2%-14%, C: 0.1%-0.2%, Mn: 0.2%-0.5%, Si: 0.2%-0.5%, with the sum of the mass percentages of the above components being 100%. The welding sheath is made of Inconel 718 alloy strip. This invention also discloses a method for preparing and applying the metal flux-cored welding wire for wind turbines. This invention solves the problem of pitting corrosion and abrasive wear on the surface of high-speed gears in existing wind turbines, particularly in environments with high corrosion resistance requirements, such as offshore and desert environments with high wear resistance requirements, resulting in corrosion pits and wear microcracks.

This invention relates to the field of stainless steel materials technology, specifically to a nickel-chromium-molybdenum-containing marine splash zone-resistant and corrosion-inhibiting stainless steel material and its preparation process. The chemical composition of the stainless steel material, by mass percentage, includes: carbon ≤0.04%, silicon 0.5%-0.8%, manganese ≤0.8%, phosphorus ≤0.02%, sulfur ≤0.0015%, chromium 22%, nickel 10%-11%, molybdenum 3.0%-3.5%, copper 1.2%-1.5%, titanium 0.2%-0.25%, niobium 0.1%-0.15%, with the remainder being iron. This invention's stainless steel material, through scientific chemical composition design, constructs a stable basic corrosion-resistant system. Simultaneously, the introduction of specific elements exerts a synergistic effect, effectively enhancing the stability and density of the passivation film on the material surface. This significantly improves the material's resistance to pitting corrosion in marine splash zones, reduces the risk of chloride ion damage to the passivation film, effectively inhibits intergranular corrosion, greatly improves the material's corrosion resistance stability, and extends its service life in harsh marine environments.

The invention discloses superaustenitic stainless steel based on the synergistic effect of Mo and N and a preparation method of the superaustenitic stainless steel, and belongs to the technical field of high-performance metal materials. The stainless steel comprises the following components in percentage by mass: 26.0%-26.5% of Cr, 3.48%-4.52% of Mo, 0.29%-0.51% of N, 23.0%-25.0% of Ni, less than or equal to 0.01% of C, 0.40%-0.65% of Mn and the balance of Fe and inevitable impurities. According to the method, on the premise that the PREN value is kept basically unchanged, the point corrosion resistance of the stainless steel in a chloride ion-containing medium is remarkably improved by synergistically reducing the Mo content and increasing the N content and utilizing the interaction effect of Mo and N. The synergistic effect is embodied in inhibiting pitting initiation, slowing down pitting extension, promoting repassivation and forming a more protective passive film structure. The material is especially suitable for harsh corrosive environments such as offshore oil and gas exploitation and seawater desalination.

The invention belongs to the technical field of metal material surface corrosion prevention, and discloses a pitting-resistant corrosion inhibitor coated GO-Al-based composite coating as well as a preparation method and application of the pitting-resistant corrosion inhibitor coated GO-Al-based composite coating. The method comprises the following steps: adding aluminum powder into a GO aqueous solution and a corrosion inhibitor aqueous solution for ultrasonic dispersion; carrying out static settlement, filtering, washing and vacuum drying to obtain modified aluminum powder, and mixing the modified aluminum powder with alumina powder to obtain mixed powder; under the pressure of 0.6-0.8 MPa, carrying out sand blasting treatment on the magnesium alloy matrix by adopting silicon carbide to enable the surface roughness of the magnesium alloy matrix to be 1-3 microns, so as to obtain a pretreated magnesium alloy matrix; and the mixed powder is sprayed on the surface of the pretreated magnesium alloy matrix, and the corrosion inhibitor coated GO-Al-based composite coating is prepared. The composite coating releases a corrosion inhibitor at the crack defect position, a hydrophobic adsorption film is generated, invasion of a corrosion medium and pitting corrosion of the Al coating can be effectively blocked through cooperation with graphene oxide, the corrosion resistance of the Al-based coating is enhanced, and the composite coating can be applied to the field of metal surface corrosion resistance.

The invention belongs to the technical field of metal materials, and particularly relates to rare earth-antimony synergistic alloying corrosion-resistant steel special for photovoltaic and a preparation method of the corrosion-resistant steel. The corrosion-resistant steel special for photovoltaic is prepared from, by weight, 0.04%-0.08% of C, 0.20%-0.50% of Si, 0.80%-1.50% of Mn, smaller than or equal to 0.015% of P, smaller than or equal to 0.003% of S, 1.50%-3.00% of Cr, 0.20%-0.50% of Mo, 0.10%-0.40% of Ni, 0.010%-0.030% of RE, 0.05%-0.20% of Sb, 0.02%-0.05% of Als, smaller than or equal to 0.0050% of N and the balance Fe and inevitable impurities. Wherein RE / S satisfies 3.5 < = RE / S < = 5.0, and Sb / Cr satisfies 0.03 < = Sb / Cr < = 0.08; and through a two-stage controlled rolling and controlled cooling process, a core-shell structure with rare earth sulfur oxide as a core and an antimony atom enrichment layer as a shell is formed on the ferrite grain boundary. By the adoption of the technical scheme, the grain boundary electrochemical stability can be improved, pitting corrosion resistance and intergranular corrosion resistance are remarkably enhanced, and meanwhile the excellent comprehensive performance of high strength and high toughness is obtained.

The application discloses a kind of stainless steel composite plate pitting test determination method, belong to corrosion detection technical field.The application measures the weight, length, width and thickness of pretreated sample, obtains sample original weight, sample length, sample width and sample thickness;Sample is soaked in closed environment, specified temperature ferric chloride solution, and is soaked to reach test time, after sample is removed and cleaned, obtain post-test sample;Measure the weight of post-test sample, obtain sample post-test weight;Calculate weight loss rate.The application pretreats sample before test, so that it is not completely exposed in ferric chloride solution, avoids the reaction of base layer and solution caused thereby, so that measurement result is more accurate;Weight loss rate is used to reflect the pitting resistance of stainless steel composite plate material with uniform corrosion not obvious, to evaluate pitting resistance, realizes accurately evaluating the pitting performance of stainless steel composite plate.

The application relates to the technical field of alloy materials, in particular to a magnesium alloy and a preparation method and application thereof. The magnesium alloy contains, in percentage by mass, Al: 0.05%-0.12%, Zn: 0.005%-0.02%, Mn: 0.005%-0.03%, Fe: <=0.015%, Cu: <=0.005%, Ni: 0.15%-0.25%, Si: <=0.01%, Gd: 2.5%-3.2%, and the balance is magnesium and inevitable impurities. The first manganese source, the second manganese source and the pretreated manganese powder without the controlled release layer are constructed to have different controlled release layer structures, and are added in stages when the base melt is cooled to the semi-solid window, so that the manganese element is released in sequence, the obtained magnesium alloy has high compressive strength, excellent early pitting corrosion resistance and stable late dissolution rate, and is suitable for preparing the center tube or the cone of the soluble segmented fracturing bridge plug, and effectively solves the technical problem that the existing soluble magnesium alloy cannot simultaneously have stable pressure resistance in the early stage and uniform dissolution in the late stage.

This invention relates to the field of metal corrosion detection and three-dimensional morphology analysis technology, specifically disclosing a method for identifying pitting corrosion based on three-dimensional morphology reference surface correction and fusion domain segmentation. The method includes: S1: acquiring three-dimensional morphology data of the metal surface; S2: obtaining potential pitting regions based on the three-dimensional morphology data; S3: dividing the potential pitting regions into pitting and fusion pits based on their area and average area, and further subdividing fusion pits into multiple pitting pits using distance transformation and watershed algorithms to obtain a set of pitting pits; S4: calculating the geometric parameters of the pits based on the set of pitting pits; S5: generating a parameter table and a visualization annotation map based on the set of pitting pits and their geometric parameters. This invention can automatically identify all target defects, including shallow pits and fusion pits, improving detection efficiency while ensuring modeling accuracy. It is applicable to the detection of pitting defects and mechanical property analysis of metal components of different sizes and operating conditions.

The invention is suitable for the technical field of computer vision and artificial intelligence, and provides an improved YOLOv8-based ship plate steel corrosion detection model and method, and the model is improved on the basis of a YOLOv8 architecture: in a backbone network, a C2f-Star module is used to replace an original C2f module, and the C2f-Star module is connected with the original C2f module through a star-shaped branch structure comprising a plurality of parallel convolution paths. The multi-scale extraction capability of small-scale corrosion characteristics is enhanced; a CAA attention module is embedded between a backbone network and a neck network, and the CAA attention module adaptively focuses a corrosion area and inhibits complex background interference through serially connected channels and a space attention mechanism. According to the model, the detection rate of small-scale pitting corrosion in a ship plate steel corrosion detection task is remarkably increased, the false detection rate under the background of oil contamination, coating falling and the like is effectively reduced, meanwhile, the high reasoning speed is kept, and the model is suitable for real-time automatic detection in the field of ship maintenance.

The invention discloses a corrosion-resistant centrifugal pump impeller and a preparation method thereof. According to the impeller, stainless steel or nickel-based alloy serves as a base body, a composite corrosion-resistant layer sequentially comprising a solid diffusion barrier layer, a Ni-Cr-Mo series metal bonding layer, an iron-based metal amorphous corrosion-resistant layer and a sol-gel sealing layer from inside to outside is constructed on the surface, making contact with a medium, of a flow channel, and pores are filled with the sealing layer so that the apparent porosity can be smaller than or equal to 1.5%. The composite layer is subjected to thickness gradient distribution along the radial direction, so that the total thickness of the corrosion sensitive area is 1.2-3.0 times of that of the middle area; a hub shaft hole is provided with an electric insulation sleeve, so that the wet insulation resistance is larger than or equal to 1 megohm. According to the scheme, synergistic improvement of interface protection, pore blocking, sensitive area reinforcement and galvanic couple isolation is achieved, pitting corrosion resistance and durability of the impeller are remarkably improved, and the impeller is suitable for working conditions such as seawater and chlorine-containing circulating water.

The invention discloses a bevel gear pair time-varying meshing stiffness calculation method considering tooth surface pitting corrosion and gluing damage, and aims to solve the problems that a straight bevel gear pair time-varying meshing stiffness calculation method does not consider the real section shape of a gear and neglects the influence of tooth surface pitting corrosion and gluing damage on the contact state of a gear pair. And the calculation precision of the time-varying meshing stiffness of the straight bevel gear pair is low. According to the method, a cantilever beam model of the straight bevel gear is established, the influence of friction force between tooth surfaces in the gear meshing process is considered, the straight bevel gear is sliced to obtain equivalent straight gears, and the time-varying meshing stiffness of the straight bevel gear pair is defined as the sum of the meshing stiffness of all the equivalent straight gears. The meshing rigidity of the equivalent spur gear is determined by calculating the stress, geometric dimension parameters, rotational inertia and cross sectional area of the equivalent spur gear, the oil film thickness, the oil film pressure, the normal oil film rigidity and the normal contact rigidity of the multi-ellipsoidal micro-convex bodies on the tooth surface of the equivalent spur gear, so that the time-varying meshing rigidity of the straight bevel gear pair is obtained.

This invention discloses a high-martensite-content, pitting-resistant NiTi alloy and its laser powder bed melting preparation method and application, belonging to the technical fields of nickel-titanium shape memory alloys, additive manufacturing, and material corrosion protection. The method involves: under inert gas protection, LPBF forming is performed using a laser with a power of 180–220 W, a scanning speed of 1085–1325 mm / s, and a scanning spacing of 80–100 μm to form an austenitic structure with orientation characteristics; subsequently, a medium-temperature annealing treatment is performed at 500–550 °C for 180–240 min to induce the austenite to transform into martensite and inherit the orientation characteristics, achieving a martensite content of 42–55%, while simultaneously promoting the uniform distribution of nano-precipitates. The prepared alloy can effectively reduce electrochemical inhomogeneity, significantly improve pitting corrosion resistance in chlorine-containing environments, and has an overpassivation potential of 1300–1600 mV, exhibiting both good functional properties and promising engineering applications.

To estimate the properties of a metallic material having a specified composition. [Solution] An estimation method comprising: a first learning process that acquires first trained model information by a learning process using training data that includes condition information about metal materials and characteristic information indicating the pitting corrosion resistance of metal materials according to the condition information; a second learning process that extracts only those characteristic information from the training data in which it is judged that pitting corrosion can occur based on predetermined criteria, and acquires second trained model information by a learning process using the extracted training data; a first estimation process that uses the first trained model information and the condition information of the metal material to be estimated to estimate to estimate information on whether or not pitting corrosion can occur according to the condition information; and a second estimation process that extracts only those estimated to be capable of pitting corrosion as a result of the first estimation process, and estimates information indicating the pitting corrosion resistance of metal materials according to the condition information of the estimated target using the condition information of the extracted estimated target and the second trained model information.

To provide a stainless steel material that has excellent overall corrosion resistance and pitting corrosion resistance in supercritical corrosion environments, and excellent low-temperature toughness in cryogenic environments. [Solution] The stainless steel material according to this disclosure has the chemical composition described in the specification, satisfies formula (1), has a yield strength of 758 MPa or less, and its microstructure consists of retained austenite of 5-30% by volume, ferrite of 0-5.0%, and the remainder being martensite, and the elemental content, yield strength, and volume fraction of the microstructure satisfy formula (2). 0.10 ≤ Cu + W ≤ 2.20 (1) 0.01YS×(Ni+12Co) / (Vγ+3.3Vα′)≧0.0036 (2) In equations (1) and (2), the elemental symbols are substituted with the content of the corresponding element in units of mass%, in equation (2), YS is substituted with the yield strength in units of MPa, Vγ is substituted with the volume fraction of retained austenite, and Vα′ is substituted with the volume fraction of martensite in units of %.

The invention relates to a method for establishing a finite element model of cold-formed thin-walled steel with comprehensive corrosion coupled with pitting corrosion. According to the method, the corrosion field is constructed through the combination of the power spectral density constraint and the pitting statistical distribution function based on the corrosion index parameters and the corrosion random field theory, so that the comprehensive corrosion trend and the overall thinning characteristic of the component can be described, and the scale change and the space randomness of the local pitting pit can be represented; and the cold-formed thin-walled steel rusted surface topography conforming to the statistical law can be generated in batches in a computer environment. And on the basis of the generated corrosion surface topography data, continuous mapping and entity reconstruction from a corrosion disturbance field to a component geometric domain are achieved through a Python program, and a three-dimensional entity model containing corrosion fluctuation and pitting depression is formed. According to the method, the problem that the random corrosion morphology is difficult to accurately generate on the component scale and is difficult to automatically convert into the finite element geometric model in the existing research is solved.

The application discloses a processing method of a high-entropy alloy, which comprises first laser action, second laser action, electric field action and He + ion irradiation, coupling of the three means, and can realize improvement of the corrosion resistance of the high-entropy alloy, and through accurate matching and regulation of multiple process parameters, a synergistic effect is realized. Specifically, a certain amount of He + ion irradiation can improve the residual stress distribution and mechanical properties of the surface layer of the high-entropy alloy, the electric field action can improve the diffusion of the composition of the high-entropy alloy, and the laser action can optimize the microstructure, so that the pitting corrosion resistance, the crevice corrosion resistance and the stress corrosion resistance of the high-entropy alloy can be significantly improved as a whole, the comprehensive corrosion resistance of the high-entropy alloy is significantly enhanced, and the market application value of the high-entropy alloy is increased, so as to meet the demand of nuclear power plants for corrosion-resistant materials.

The invention discloses a design method of a seal ring sleeve tooth-shaped chain, and belongs to the technical field of tooth-shaped chains. A tooth-shaped design thought of combining a transition arc structure and an inner-outer composite meshing mechanism is adopted, and the tooth-shaped included angle is reduced by optimizing the arc of a tooth part of a chain plate; continuous abrasion caused by top cutting interference between the tooth top of the chain wheel and the tooth bottom of the chain plate in the actual transmission process is avoided, and stress pitting corrosion and aggravation of abrasion caused by too small instant contact face of meshing of the chain wheel and the chain are also avoided. The sheet type designed by adding a transition circular arc and an inner-outer composite meshing mechanism has better meshing performance in actual transmission, so that the phenomena of continuous wear, aggravated wear, tooth skipping, chain falling, loud noise and the like on a non-pavement bad road surface are fundamentally solved, and further chain system model selection is provided for the majority of motorcycle users.