139 results about "Corrosion current density" patented technology

The invention provides a method, a device and equipment for predicting corrosion current and corrosion of steel bars in concrete in a low-pressure environment, and belongs to the technical field of engineering simulation modeling. The method comprises the following steps: establishing a coupling transmission model in concrete considering oxygen concentration, sulfate ion diffusion behavior and chloride ion diffusion behavior; building a reinforcement corrosion current density and corrosion depth prediction model for predicting the number of charges at different positions of the reinforcement in the concrete, and calculating the corrosion depth and the corrosion product content based on the corrosion current density; and establishing a linear elastic damage model for simulating concrete damage evolution caused by steel bar corrosion according to the corrosion product content output by the steel bar corrosion current density prediction model so as to realize accurate prediction of corrosion and damage. According to the method, oxygen concentration changes under low air pressure are considered, oxygen diffusion is described, output of a transmission model serves as a dynamic variable to be introduced into the corrosion current calculation process, and the accuracy of corrosion current and steel bar corrosion prediction is improved.

The invention belongs to the technical field of corrosion and protection simulation analysis, and particularly relates to a multi-physics coupling corrosion simulation method for a metal material in a seawater environment, which comprises the following steps: firstly, carrying out stress and deformation calculation on a structure, and then, carrying out analysis fitting on a polarization test result of the material according to the electrochemical corrosion condition of the structure in seawater, so as to obtain a simulation result; and finally, according to the mutual influence effect between stress and electrochemistry, establishing a coupling path, realizing multi-physics coupling simulation, and quickly calculating to obtain the corrosion potential and the corrosion current density on the surface of the structure and the corrosion rates at different positions, thereby determining the most sensitive position of corrosion. By establishing an independent simulation boundary module database, rapid calling and reading of simulation boundary parameters are achieved, rapid iterative calculation of long-period corrosion evolution is achieved, corrosion evaluation efficiency is greatly improved, and the problems that in the equipment service process, seawater corrosion prediction precision is low, and the test period is long are effectively solved.

The invention relates to the technical field of processing, testing or inspection of aircraft parts, and provides a method for detecting surface defects of an aluminum alloy plate with an epoxy coating. The method comprises the following steps: applying an epoxy coating doped with a zinc yellow pigment to an anodic oxide film to construct a coating test piece with a color difference indication function, and placing the coating test piece in a coastal atmospheric environment for exposure sampling. In the detection process, the gloss loss rate, the chromatic aberration, the contact angle, the defect area proportion and the corrosion current density are collected, a dynamic correction coefficient is calculated according to the hydrolysis degree of the zinc yellow pigment, all parameter thresholds are adjusted in a self-adaptive mode, and a threshold set is constructed. And in combination with scanning electron microscope image segmentation and Tafel extrapolation analysis, multi-source indexes are fused to judge whether the coating is invalid. According to the method, the hydrolysis behavior of the zinc yellow pigment can be tracked in real time, the judgment standards of optical, morphology and electrochemical indexes are automatically corrected, and the accuracy and reliability of failure detection of the epoxy coating aluminum alloy plate under the coastal service condition are improved.

The invention belongs to the technical field of surface engineering protective coatings, and discloses a nitrogen heterocyclic compound modified corrosion-resistant high-entropy alloy coating as well as a preparation method and application thereof. The preparation method comprises the following steps that firstly, a magnetron sputtering technology is adopted, a CoCrFeMnNi target serves as a cathode target material, and a corrosion-resistant high-entropy alloy coating is obtained through deposition on the surface of a base body; and then, in a three-electrode system, the corrosion-resistant high-entropy alloy coating is placed in an electrolyte containing a nitrogen heterocyclic onium salt compound to be subjected to electro-deposition, and the nitrogen heterocyclic compound modified corrosion-resistant high-entropy alloy coating is prepared. The corrosion-resistant inorganic-organic hybrid coating prepared by the invention has excellent corrosion resistance, can keep high stability and durability in a complex corrosion environment, and has relatively high corrosion potential and relatively low corrosion current density. The coating can remarkably prolong the service life of a structural base material, is suitable for various harsh working conditions, and provides an efficient and reliable protection solution for industrial application.

The invention discloses an aging treatment optimization method for inhibiting precipitation of a gamma2 phase in solid-solution-state duplex stainless steel. Aiming at the problems of excessive precipitation of a gamma2 phase and poor stability of a passivation film caused by the existing process (700 DEG C, 8-32 hours), the precipitation amount of the low-chromium gamma2 phase at the alpha / gamma phase boundary is reduced by shortening the aging time to 0.5-4 hours. The method comprises a solution treatment stage (1100 DEG C heat preservation for 2 hours and air cooling), an aging treatment stage (700 DEG C heat preservation for 0.5-4 hours) and furnace cooling. The pitting potential of the optimized material is remarkably improved, the corrosion current density is reduced, the pitting corrosion resistance is improved by 30% or above, meanwhile, complex equipment or alloy addition is avoided, and the method is suitable for industrial production. Experiments show that gamma 2 phase precipitation can be effectively inhibited within 4 hours of aging, the stability and chloride ion erosion resistance of a passive film are enhanced, formation of corrosion holes is reduced, and the service life of the material in nuclear energy, ocean and other environments is remarkably prolonged.

The invention relates to an L450 grade pipeline steel hot-rolled plate coil for ground gathering and transportation and a production method thereof. The chemical composition of the steel is C: 0.061%-0.070%, Si: 0.15%-0.25%, Mn: 0.39%-0.48%, P≤0.012%, S: 0.0028%-0.003%, Als: 0.030%-0.045%, Nb: 0.032%-0.038%, Ti: 0.020%-0.023%, Cu: 0.34%-0.42%, Cr: 0.32%-0.39%, N≤0.004%, and the remainder is iron and impurities. The yield strength of the hot-rolled coil product is 465-478 MPa, the tensile strength is 572-588 MPa, the elongation after fracture is ≥36.5%; the Charpy impact energy Akv at -40°C is ≥308 J; the corrosion rate is 0.0234-0.0270 mm / a, the corrosion potential is ≥-0.452 V, and the corrosion current density is ≤1.06×10 ‑5 A.cm ‑2 .

The invention discloses a high-strength corrosion-resistant Al-Zn-Mg-Cu-Sc-Zr alloy plate and a preparation method thereof, and belongs to the technical field of aluminum alloy materials. The alloy comprises the following components in percentage by mass: 7.0%-8.0% of Zn, 1.5%-2.0% of Mg, 1.4%-1.8% of Cu, 0.05%-0.15% of Sc, 0.05%-0.15% of Zr, less than or equal to 0.05% of Si, less than or equal to 0.1% of Fe, less than or equal to 0.01% of Mn, less than or equal to 0.01% of Cr, less than or equal to 0.01% of Ti and the balance of Al. The preparation method comprises the steps of smelting and pouring, homogenizing annealing, hot rolling, cold rolling and solid solution aging treatment. By synergistically adding Sc and Zr, a nanoscale Al3 (Sc, Zr) dispersed phase is formed, recrystallization is inhibited, grains are refined, meanwhile, grain boundary precipitated phase distribution is optimized, and the mechanical property and corrosion resistance of the alloy are improved. The tensile strength of the obtained alloy plate reaches 590 MPa or above, the yield strength reaches 540 MPa or above, the intergranular corrosion depth is smaller than or equal to 23 micrometers, the exfoliation corrosion depth is smaller than or equal to 117 micrometers, the corrosion current density is smaller than or equal to 0.53 microamperes / cm < 2 >, and the comprehensive performance is obviously superior to that of a traditional Al-Zn-Mg-Cu alloy.

The invention provides a method and equipment for calculating the flexural capacity of a steel pipe pile and a storage medium, and relates to the technical field of flexural capacity calculation, and the surface strain distribution and corrosion state of the steel pipe pile are monitored in real time through distributed optical fibers and a three-electrode system. Firstly, a spatial gradient analysis method is adopted to identify a strain mutation area as a potential damage area, corrosion current density is measured through a polarization resistance method, correction is performed in combination with a strain threshold value, and the accumulated corrosion depth is calculated. And secondly, converting the strain distribution into an amplitude sequence by using a rain flow counting method, calculating the fatigue damage degree by combining a material S-N curve, and constructing a multi-damage coupling model by combining stress amplitude, chloride ion concentration and temperature difference data to obtain the corrosion damage degree. And finally, a yield strength degradation model is established based on the service duration, factors such as strength attenuation, fatigue damage, corrosion damage and section loss are comprehensively considered, the current bearing capacity of the structure is evaluated by calculating the flexural capacity of the steel pipe column, and a grading early warning mechanism is set.

The invention belongs to the field of aluminum alloy processing, and provides a method for evaluating the corrosion resistance of an anodic oxide film and the corrosion capacity of a semi-synthetic cutting fluid, which comprises the following steps of: respectively taking a corrosive liquid or the semi-synthetic cutting fluid as an electrolyte and simulating a corrosive environment, and then taking an aluminum alloy sample as a working electrode to evaluate the corrosion resistance of the anodic oxide film and the corrosion capacity of the semi-synthetic cutting fluid; performing an electrochemical test in a corrosion environment to obtain charge transfer resistance Rct and corrosion current density Icorr, and then calculating a corrosion resistance index CI; the higher the obtained corrosion resistance index CI value is, the higher the corrosion resistance of the anodic oxide film of the aluminum alloy sample is, or the lower the corrosion capacity of the semi-synthetic cutting fluid is. And the corrosion resistance of the anodic oxide film or the corrosivity of the semi-synthetic cutting fluid can be rapidly and accurately evaluated.

The invention provides a ship lock metal structure safety detection and evaluation standardization system and method, and relates to the technical field of ship lock engineering safety detection. A distributed intelligent sensing module is obtained, and multi-dimensional dynamic parameters of a ship lock metal structure are collected through the distributed intelligent sensing module; the computer sends a starting instruction to the distributed intelligent sensing module through a preset sensor control program, receives and stores dynamic parameters returned by each sensor in real time, and establishes a timestamp index. Compared with the prior art, the method has the following beneficial effects: by integrating multi-dimensional dynamic parameters such as vibration acceleration, temperature gradient, corrosion current density and the like, the state change of the ship lock metal structure under dynamic load and severe environment can be comprehensively captured, and the sampling frequency is automatically adjusted in combination with a trigger type sampling mechanism; therefore, the transient response under the sudden load is effectively captured, early damage missed judgment caused by only monitoring static parameters is avoided, and the actual safety condition of the structure is reflected more truly.

The invention discloses silicon dioxide modified carbonyl iron powder as well as a preparation method and application thereof. According to the modified material, micron-sized carbonyl iron powder serves as a core, the surface of the modified material is coated with a nano-sized silicon dioxide layer through an improved Stober method, a core-shell structure is formed, the thermal stability and corrosion resistance of the carbonyl iron powder are remarkably improved, and the initial oxidation temperature of the carbonyl iron powder is not lower than 300 DEG C and is increased by at least 50 DEG C compared with an unmodified product. The preparation method comprises the steps of dispersion, mixed catalysis, coating reaction and post-treatment, and is simple in process and high in controllability. The invention further provides application of the modified carbonyl iron powder in an epoxy resin-based anticorrosive coating, when the filling amount is 0.1-2.0% (preferably 1.00%), the coating shows excellent anticorrosive performance in a 3.5 wt% NaCl solution, the low-frequency impedance modulus value is not lower than 7.0 * 10 < 5 > omega.cm < 2 >, and the corrosion current density is not higher than 2.15 * 10 <-8 > A / cm < 2 >. The method effectively solves the problems that the carbonyl iron powder is easy to oxidize and agglomerate and poor in corrosion resistance, and is suitable for the high-performance anti-corrosion and wave-absorbing integrated coating.

The invention discloses a preparation method for improving the corrosion resistance of a spray-formed aluminum alloy component, and belongs to the field of preparation of high-performance metal materials. According to the method, a high-frequency alternating magnetic field with specific parameters (such as the strength of 0.2 T-0. 8T and the frequency of 5kHz-50kHz) is synchronously applied in the deposition stage of spray forming, so that the magnetic field force acts on molten drops which are being solidified and a semi-solid layer. According to the method, nucleation, growth and spatial distribution of a nano precipitated phase and a nano dispersed phase are actively intervened in situ through magnetic field induced micro-area convection and interface energy regulation and control, so that the microscopic heterogeneity which is easy to cause corrosion is fundamentally optimized; compared with a conventional spray forming process without a magnetic field, according to the method, the corrosion current density of the 7075 aluminum alloy in a 3.5% NaCl solution can be reduced by about 60%, the pitting potential positive shift exceeds 80 mV, the service life of a component in a severe environment is remarkably prolonged, and the reliability of the component in the severe environment is remarkably improved.

The application belongs to the technical field of surface engineering protection, and discloses a transition metal compound composite coating, a preparation method and application thereof; wherein the transition metal compound composite coating is a composite multilayer structure, and comprises n same periodic structures deposited in sequence, and n is greater than or equal to 2; wherein each periodic structure comprises a titanium nitride coating and a niobium nitride coating. The application specifically discloses a high-conductivity strong-corrosion-resistance transition metal compound composite coating, and can solve the technical problems of high cost, high corrosion current density, low corrosion overpotential and poor conductivity in the prior art.

The invention discloses a metro steel fiber concrete structure corrosion current density time sequence prediction method fused with polarization potential monitoring signals, and the method comprises the steps: measuring corrosion current density time sequence data in a small period, taking the time sequence data in the small period as training data, constructing a corrosion current density time sequence prediction method based on a long short-term memory network (LSTM), and predicting the corrosion current density time sequence of a metro steel fiber concrete structure. According to the method, the development condition of the stray current corrosion of the steel fiber reinforced concrete structure can be accurately mastered through the corrosion current density time sequence prediction, so that the stray current corrosion early warning is realized, and the early warning of the stray current corrosion of the steel fiber reinforced concrete structure is realized. And an accurate basis is provided for carrying out stray current corrosion protection in time.

The invention relates to an MgF2-PDA-EGCG magnesium alloy composite coating as well as a preparation method and application thereof. The MgF2-PDA-EGCG magnesium alloy composite coating sequentially comprises a MgF2 coating, a PDA coating and an EGCG coating from inside to outside. The preparation method comprises the following steps: (1) carrying out surface treatment on a magnesium alloy substrate; (2) immersing the treated magnesium alloy substrate into a hydrofluoric acid solution to obtain a magnesium alloy substrate-F; and (3) the magnesium alloy substrate-F is immersed into a dopamine hydrochloride solution and then immersed into an epigallocatechin gallate solution, and the MgF2-PDA-EGCG magnesium alloy composite coating is obtained. The MgF2-PDA-EGCG composite coating provided by the invention integrally presents an organic-inorganic composite structure, shows higher charge transfer impedance and lower corrosion current density in electrochemical impedance spectroscopy and polarization curve tests, has the comprehensive corrosion resistance improved by 1-2 orders of magnitude, and also has good antibacterial activity.

The present application relates to the technical fields of fuel cell technology, more particularly to a stainless steel for fuel cell polar plate and a surface modification method thereof. The element composition of the stainless steel comprises Cr: 20-30%, Ni: 0-20%, Mo: 3-10%, N: 0.05-1.5%, C: 0-0.03%, Si: 0-0.6%, Mn: 0-0.5%, Nb: 0-0.5%, W: 0-0.2%, Sn: 0-1%, Au: 0-0.5%, Ta: 0-0.5%, Al: 0-0.02%, Cu: 0-0.2%, P: 0-0.05%, S: 0-0.05%, Ce: 0-0.1%, and Fe makes up the balance. The surface of the stainless steel is removed from the surface passivation film and impurities and a new passivation film is formed, and the self-corrosion current density can be less than 1 mu A / cm 2 , and meanwhile has excellent electric conductivity.

The present invention relates to the field of corrosion monitoring technology, specifically to an intelligent pipeline corrosion monitoring and protection system. The system includes: a dynamic potential perturbation measurement module, a local micro-area scanning module, a corrosion rate calculation module, a corrosion risk distribution analysis module, and an environmental parameter compensation module. In the present invention, by measuring the reference potential on the pipeline surface and applying instantaneous perturbations, combined with current change differential operations, the corrosion process is dynamically tracked, the real-time response capability is improved, a microelectrode array is arranged to cover corrosion hotspots, precise measurement is achieved, spatial resolution is improved, the current response change rate is calculated, the corrosion current density is calculated based on the electrochemical properties of the material, the corrosion rate is dynamically predicted, the regional distribution is analyzed based on the corrosion rate changes, the accuracy of the corrosion risk assessment is optimized, environmental factors are monitored, perturbation parameters are adjusted, interference is compensated, and monitoring accuracy under different working conditions is ensured, ensuring data stability and optimizing protective measures.

The present invention discloses a method for achieving corrosion resistance treatment on the surface of titanium alloy by means of laminated ironing and electrodeposition. First, the surface of the titanium alloy substrate is subjected to laminated ironing to form a nanocrystalline transition layer on the surface, increasing the dislocation density and introducing appropriate internal stress, effectively enhancing the surface residual stress of the titanium alloy. Then, the surface is polished at low frequency to obtain a reasonable surface roughness and improve the electrochemistry deposition reaction activity. Then, electrochemical deposition surface treatment is carried out. Sodium sulfate, methanol and titanium dioxide nanoparticles are added to the electrochemistry deposition solution to improve the deposition efficiency of the electrochemistry coating. The method of the present invention improves the corrosion resistance of the titanium alloy. The electrochemical impedance is increased by two orders of magnitude, the corrosion potential is shifted positively, the corrosion current density is reduced by two orders of magnitude, and the integrity of the electrodeposition coating is improved, reducing the coating defects.

The invention discloses a preparation method of a cobalt phthalocyanine PANI doped composite coating on the surface of a metal bipolar plate. The method comprises the following steps: carrying out surface roughening and acid activation pretreatment on the metal bipolar plate; the preparation method comprises the following steps: preparing precursor slurry from cobalt phthalocyanine and an aniline monomer in an acid environment through in-situ oxidative polymerization; the preparation method comprises the following key steps: introducing an independently designed and synthesized sulfonyl-bis-imidazoline-containing electron bridging aromatic ring as a multifunctional dopant, and effectively bridging a polyaniline chain and cobalt phthalocyanine molecules through the strong electron withdrawing effect of sulfonyl and the coordination synergistic effect of a bis-imidazoline ring to construct a stable three-dimensional conductive network; and finally, coating an activated substrate with the obtained composite slurry, and carrying out heat treatment to form a compact coating. The contact resistance of the composite coating is lower than 8.5 m omega.cm, the corrosion current density is lower than 0.1 mu A / cm, the binding force of the coating reaches the 5B grade, and the composite coating has high conductivity, high corrosion resistance and excellent interface stability.

The application discloses a kind of based on the coupling of electrochemical parameter gap corrosion evaluation method and device, it is related to electrochemical corrosion evaluation technical field.Gap corrosion evaluation method includes the following steps: based on gap structure establishes oxygen concentration cell, determines anode, cathode and its surface area;In the oxygen-poor medium environment, the anodic polarization curve of target material is measured, the cathodic polarization curve of target material is measured in the oxygen-rich medium environment, obtains anode current density-potential relationship and cathode current density-potential relationship;According to the electrochemical balance formula that total cathode current is equal to total anode current, the coupling potential of oxygen concentration cell is calculated, and further the gap corrosion current density corresponding to coupling potential is obtained, and the gap corrosion rate is calculated according to gap corrosion current density.The gap corrosion evaluation method provided by the application is suitable for the rapid prediction of initial stage of gap corrosion, with the characteristics of convenient, high repeatability, the result is more accurate.

The invention discloses a passivation solution for improving the corrosion resistance of X40CrMoVN16-2 high-nitrogen martensitic stainless steel, and belongs to the technical field of stainless steel surface treatment. The passivation solution is prepared from, by mass, 6%-10% of citric acid, 3%-5% of hydrogen peroxide, 0.8%-1.2% of sodium molybdate, 0.1%-0.16% of lauryl sodium sulfate and 0.06%-0.12% of nano-silica sol, the passivation temperature is 35-45 DEG C, and the passivation time is 50-60 min. The self-corrosion current density of a sample passivated by the passivation solution is reduced to 0.076 [mu] A.cm <-2 > from 0.892 [mu] A.cm <-2 > of an unpassivated sample, the pitting potential is increased to 1.54 V from-1.55 V of the unpassivated sample, and the corrosion resistance of the X40CrMoVN16-2 high-nitrogen martensitic stainless steel is effectively improved.

This invention relates to the technical fields of aircraft component processing, testing, and inspection, and provides a method for detecting surface defects in epoxy-coated aluminum alloy plates. The method involves applying an epoxy coating containing zinc yellow pigment onto an anodic oxide film to construct a coated test piece with color difference indication function, which is then exposed to a coastal atmospheric environment for sampling. During the detection process, data such as gloss loss rate, color difference, contact angle, defect area ratio, and corrosion current density are collected. A dynamic correction coefficient is calculated based on the degree of zinc yellow pigment hydrolysis, adaptively adjusting the threshold values ​​of each parameter and constructing a threshold set. Combining scanning electron microscopy image segmentation and Tafel extrapolation analysis, multi-source indicators are integrated to determine whether the coating has failed. This method can track the hydrolysis behavior of zinc yellow pigment in real time, automatically correct the judgment criteria for optical, morphological, and electrochemical indicators, and improve the accuracy and reliability of failure detection of epoxy-coated aluminum alloy plates under coastal service conditions.

The invention relates to the technical field of wave-absorbing materials, in particular to a SiBCN-Fe ceramic corrosion-resistant wave-absorbing material and a preparation method and application thereof. The preparation method comprises the following steps: preparing a hyperbranched PBSZ-SiH polymer in an argon atmosphere; under the protection of argon, ferric acetylacetonate is dissolved in anhydrous xylene, and then the hyperbranched PBSZ-SiH polymer is added for a reaction; collecting a solid phase to obtain a PBSZ-Fe ceramic precursor; heating the PBSZ-Fe ceramic precursor, and carrying out a cross-linking reaction; and grinding a product obtained after the cross-linking reaction into powder, and then performing high-temperature pyrolysis in an argon atmosphere to obtain the SiBCN-Fe ceramic. According to the SiBCN-Fe ceramic corrosion-resistant wave-absorbing material, in a 3.5 wt% NaCl / H2O solution, the corrosion potential (Ev) is 0.035 V, the corrosion current density (Icorr) is 6.295 * 10 <-7 > Acm <-2 >, and the SiBCN-Fe ceramic corrosion-resistant wave-absorbing material is superior to most corrosion-resistant wave-absorbing materials; the effective absorption bandwidth (EAB) of 8.16 GHz under 2.7 mm and the minimum reflection loss of-32.2 dB under 2 mm are achieved, and excellent corrosion resistance and excellent wave absorbing performance are achieved.

A micro-arc oxidation treatment method for a magnesium alloy containing an LPSO phase, which adopts an electrolyte system mixed with three kinds of salts, i.e., a metallate, a silicate and a phosphate, and combines two-step micro-arc oxidation treatment to control the generation of ceramic phases in the oxide film layer structure and embed a large number of exposed LPSO phases in the micro-arc oxidation film, so that the obtained micro-arc oxidation film has small porosity and pore size, a smooth surface and no micro-cracks, the porosity is less than or equal to 9%, the micro-arc oxidation film has a pore size of 140-1100 nm and an average pore size of less than or equal to 1 micrometer, and the corrosion resistance of the magnesium alloy is significantly improved, the self-corrosion current density of the magnesium alloy is reduced by three orders of magnitude compared with that before the micro-arc oxidation treatment, the self-corrosion current density is less than or equal to 3.588*10 ‑8 A cm ‑2 , and the corrosion resistance efficiency is greater than or equal to 1208%.

The application relates to the field of magnesium alloy corrosion prevention technology and discloses a method for improving the corrosion resistance of magnesium alloy, which comprises the following steps: uniformly mixing carbon dioxide and oxygen with a mass fraction of 99.999% in proportion to obtain a mixed atmosphere; polishing and polishing the magnesium alloy, performing ultrasonic cleaning with ethanol, and then performing thermal oxidation treatment in a heating device into which the mixed atmosphere is introduced, and keeping warm, so that an outer layer film of MgCO3 and CaCO3 and an inner layer film of a composite protective film of CaO, MgO and Al2O3 are generated on the surface of the magnesium alloy; the method provided by the application makes the outer layer film on the surface of the magnesium and the magnesium alloy have a thickness of 95-125 nm, the inner layer film has a thickness of 30-40 nm, the composite film is flat and dense, has good adhesion, and significantly improves the corrosion resistance of the magnesium and the magnesium alloy, the electrochemical impedance is increased by 10 times, the corrosion current density is correspondingly reduced by 10 times, and the salt spray test shows that the corrosion resistance time is increased from 24 h to 144 h.

The invention provides a super-wear-corrosion-resistant high-temperature iron-based amorphous alloy and relates to the field of amorphous alloy materials, the chemical formula of the iron-based amorphous alloy is Fea( Co + Ni) bCrc (W + Nb + Ta) dMeC10B4, and M is any one of Y, Dy, Er, Tm and Yb. The amorphous alloy has the glass transition temperature as high as 930K and the crystallization temperature as high as 950K, and has good high-temperature stability; meanwhile, the material has excellent amorphous forming ability, a block material with the three-dimensional size not smaller than 2 mm can be obtained, the self-corrosion current density of the material in a 3.5% NaCl solution is as low as 1.32 * 10 <-6 > A / cm < 2 >, the corrosion rate of the material in an aqua regia solution is 0.1 mm / a, and the material has wear resistance as low as 6.17 * 10 <-6 > mm < 3 > / Nm and has excellent corrosion resistance and wear resistance.

The invention discloses rare earth Er-doped CrMo steel and a thermodynamic-based preparation method thereof, and relates to the technical field of alloy materials. According to thermodynamic calculation of a phase diagram, the range of the adding amount of Er is obtained through phase change, the mechanical property of the iron-based alloy is improved by controlling the change of the Er element content and through the phase change, and refining of the structure and synergistic enhancement of the performance are achieved by adopting a non-consumable electric arc furnace for smelting and controlling the cooling rate and the annealing / tempering treatment process. And through molten steel purification and grain refinement of rare earth Er, an action mechanism of a dispersion phase is formed, and the tensile strength, microhardness and corrosion resistance of the material are remarkably improved. Experimental results show that when the Er content is 0.1%, the tensile strength of the alloy steel is improved by about 44.6%, the hardness is improved by about 10.7%, the corrosion potential is improved by 10%, the corrosion current density is reduced by 81.8%, and the performance is optimal. The method is simple, components are controllable, and the method is suitable for large-scale industrial preparation of the structural steel.

The invention relates to the technical field of coatings, in particular to a graphene / aluminizing composite coating and a preparation method thereof, and the preparation method comprises the steps of base material treatment, magnetron sputtering deposition of a graphene layer, slurry preparation, aluminizing treatment and post-treatment. The graphene layer is deposited on the surface of the stainless steel base material to serve as a bottom layer protective film, the Al4C3 transition layer is formed through the low-temperature slurry aluminizing technology, and the interface bonding strength and the hydrogen resistance are remarkably improved. The problems that a traditional coating is insufficient in corrosion resistance, poor in hydrogen resistance and high in contact resistance can be effectively solved, the hydrogen resistance factor of the obtained composite coating reaches 1.2 * 10 < 8 > omega.cm < 2 >, the interface bonding strength is 50 MPa, the contact resistance is 0.8 m omega.cm < 2 >, and the corrosion current density is reduced by 99.6%.

The invention provides a CoCrNi-based high-entropy alloy material and a preparation method of the CoCrNi-based high-entropy alloy material. The chemical expression of the CoCrNi-based high-entropy alloy material is as follows: (CoCrNi) (100-x-y) Al < x > Ti < y >, wherein the atomic ratios of Co, Cr and Ni are the same, the value of x is more than or equal to 5 and less than or equal to 10, and the value of y is more than or equal to 5 and less than or equal to 10. According to the CoCrNi-based high-entropy alloy material, Al and Ti are introduced into the CoCrNi-based high-entropy alloy material, and an FCC + L12 + BCC + B2 four-phase heterostructure is formed by accurately regulating and controlling the content of Al and Ti elements and the type, particle size and distribution of a precipitated phase. The L12 precipitated phase size of the (CoCrNi) 90Al5Ti5 alloy is about dozens of nm; along with the increase of the contents of Al and Ti, the size of an L12 precipitated phase is gradually reduced. The CoCrNi-based high-entropy alloy material is high in yield strength, low in alloy corrosion current density and good in ductility.

This application provides a method, apparatus, and equipment for predicting corrosion current and rust in reinforced concrete under low-pressure environments, belonging to the field of engineering simulation modeling technology. The method includes: establishing a coupled transport model within the concrete considering oxygen concentration, sulfate ion diffusion behavior, and chloride ion diffusion behavior; establishing a model for predicting the corrosion current density and corrosion depth of the reinforcing steel, used to predict the charge number at different locations within the reinforcing steel, and calculating the corrosion depth and rust product content based on the corrosion current density; and establishing a linear elastic damage model, used to simulate the evolution of concrete damage caused by steel corrosion based on the rust product content output by the steel corrosion current density prediction model, thereby achieving accurate prediction of rust and damage. This method considers changes in oxygen concentration under low pressure, and by describing oxygen diffusion, incorporates the output of the transport model as a dynamic variable into the corrosion current calculation process, improving the accuracy of corrosion current and steel corrosion prediction.