78 results about "Corrosion current density" patented technology

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 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 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 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 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 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.

The application discloses a kind of nuclear reactor coating materials.For improving the surface performance of zirconium alloy in nuclear reactor, Cr base layer, CrN binding layer, CrNiN top layer are prepared on its surface.Research shows, with the increase of Ni element content in CrNiN top layer, the corrosion resistance of coating presents first promotion and then reduces the trend, the binding strength of coating presents first promotion and then tends to be stable trend.Considering production cost and material performance, the optimal test sample in self-corrosion current density is 1.62x10 ‑9 A·cm ‑2 , binding strength is 35.9MPa.In addition, although the binding strength of coating material is hardly affected by liquid nitrogen treatment, but can further improve its corrosion resistance.

The invention discloses a high-entropy alloy-carbon-based composite coating for a fuel cell metal bipolar plate and a preparation method of the high-entropy alloy-carbon-based composite coating, and belongs to the technical field of fuel cells. The high-entropy alloy-carbon-based composite coating sequentially comprises a high-entropy alloy transition layer and a carbon-based composite coating from inside to outside, wherein the high-entropy alloy transition layer is combined with a metal matrix and comprises at least five elements selected from Cr, Al, Ti, Nb, Mo, Zr, Hf, Ta, W, V, Ni, Si and Co; the carbon-based functional layer is located on the surface of the high-entropy alloy transition layer, and high-entropy alloy nanocrystals / clusters are carbides of the high-entropy alloy transition layer; and the high-entropy alloy transition layer and the high-entropy alloy nanocrystalline / cluster doped carbon-based functional layer are sequentially formed on the surface of the metal base material through magnetron sputtering deposition. The high-entropy alloy-carbon-based composite coating provided by the invention is strongly combined with a metal matrix, and has ultralow corrosion current density, ultralow interface contact resistance and high durability in a severe environment of a fuel cell.

The invention relates to the technical field of surface protection of metal bipolar plates for fuel cells, in particular to a titanium metal matrix surface oxygen gradient composite oxide coating and a preparation method and application thereof. The oxygen gradient composite oxide coating on the surface of the titanium metal matrix is a coating growing on the titanium metal matrix in situ, in the coating, from the titanium metal matrix to the outside, the oxygen concentration is firstly increased in a gradient mode and then decreased in a gradient mode, and the structure is TiOx-TiO2-TiOx, and 2, the coating is combined with a titanium metal matrix, so that a continuous Ti-TiOx-TiO-TiOx composite structure is formed. The oxygen gradient composite oxide coating on the surface of the titanium metal matrix has corrosion resistance and electrical conductivity, the interface contact resistance is smaller than 10 m omega.cm < 2 >, and the corrosion current density t in a simulated fuel cell environment is achieved; the method is suitable for surface protection of the titanium metal bipolar plate of the proton exchange membrane fuel cell.

The application provides a method for preparing an aluminum electrode by molten salt-ultrasonic synergistic modification and application, and relates to the technical field of metal electrode material smelting and preparation. The method comprises raw material configuration and mixing, construction of a molten salt / aluminum liquid two-phase reaction system, ultrasonic synergistic molten salt etching and in-situ metal loading, selective interface screening and directional transport, ultrasonic driving interfacial migration and dispersion anchoring, cooling and solidification, and finally obtaining an MXene dispersed embedded aluminum-based composite anode material. The obtained MXene sheet layer has a thickness of 10-500-nm, a lateral size of 200nm-20um, and a surface rich in -F, -O and -Cl functional groups, and the loaded metal exists in the form of surface adsorption or interlayer embedding. The aluminum-based composite anode material prepared by the application can effectively inhibit the hydrogen evolution side reaction and self-corrosion behavior, reduce the corrosion current density, improve the anode utilization rate and maintain high discharge performance, and can be applied to aluminum-air batteries, aluminum-oxygen batteries, aluminum-ion batteries and other energy storage devices with aluminum as the negative electrode, and is also suitable for the fields of metal corrosion prevention and interface regulation.

The embodiment of the application discloses diamond-based composite wave-absorbing material; the method comprises the following steps: S1, the surface of nano-diamond particles is graphitized to obtain graphitized diamond composite particles; S2, the graphitized diamond composite particles are formed by molding to obtain a diamond-based composite wave-absorbing material blank; S3, the diamond-based composite wave-absorbing material blank is treated by high temperature and high pressure to obtain the diamond-based composite wave-absorbing material; the diamond-based composite wave-absorbing material has a minimum reflection loss value of -61.47 dB at 5.5 mm, the widest effective absorption bandwidth can reach 4.0 GHz at 2.7 mm, the Vickers hardness is between 40 and 60 GPa, the material is superhard, the normal temperature thermal conductivity is between 3.4 and 3.7 W / m*K, the initial oxidation temperature is between 1100 and 1250 DEG C, the corrosion current density is between 10 ‑6 ~10 ‑7 A / cm 2 , the self-corrosion potential is between -200 and 0 mV, the corrosion rate is between 0.001 and 0.005 mm / a, and the material is very corrosion resistant.

The invention discloses a multi-dimensional quantitative detection method for microbial corrosion resistance of Cr-containing steel. The method comprises the following steps: a microbial challenge test: inoculating sulfate reducing bacteria into a culture medium, and exposing a sample in a microbial environment; performing quantitative analysis on corrosion products: performing ultrasonic rust removal on the sample by using an acid pickling solution, then calculating a weightlessness corrosion rate, and quantifying the adhesion amount of microorganisms on the surface of the sample; multi-mode electrochemical testing: monitoring the open-circuit potential and linear polarization resistance of the sample, and performing electrochemical impedance spectroscopy and potentiodynamic polarization curve testing to obtain corrosion current density and polarization resistance; surface analysis: analyzing the corrosion morphology and element distribution of the sample through a scanning electron microscope and an energy disperse spectroscopy, and determining the chemical state of the chromium element by adopting X-ray photoelectron spectroscopy to obtain the stability and the sulfur content of a passive film; and evaluating the corrosion degree: establishing a coupling model of the corrosion current density, the polarization resistance, the passivation film stability, the microorganism adhesion amount and the sulfur content, and calculating the corrosion degree.

The present application belongs to the technical field of copper alloy, and particularly relates to a wear-resistant and corrosion-resistant high-manganese copper alloy and a preparation method thereof, characterized by the following composition by weight percentage (wt.%): Mn: 20% to 35%, Al: 5% to 7%, Ni: 10% to 14%, and the balance of Cu and inevitable impurities, with the total percentage of all impurities being not more than 0.5%, and the content of any one of Pb, Sn, Si, Zn, P and S being not more than 0.1%. The preparation method comprises the following steps: 1) batching; 2) smelting; 3) pouring; and 4) solid solution treatment, to obtain the wear-resistant and corrosion-resistant high-manganese copper alloy. The present application has the following beneficial effects: innovative alloy composition, tensile strength up to 585 MPa, yield strength up to 296 MPa, hardness up to 305 HV, friction coefficient as low as 0.43, corrosion current density as low as 3.95 x 10 ‑6 A / cm 2 , and excellent comprehensive performance, and can be widely applied to pump bodies, valve bodies, pipelines, propellers and other parts in marine environments and other occasions with high requirements for wear resistance and corrosion resistance.

The invention relates to a pair of hepatic portal blocking forceps. After the nitrided stainless steel hepatic portal blocking clamp is subjected to vacuum annealing, the cooling rate greatly affects the corrosion resistance of the stainless steel hepatic portal blocking clamp. Researches show that when the cooling rate is 2.5 DEG C / min-6. 3 DEG C / min, the self-corrosion current density of the hepatic portal occlusion clamp can be lower than 2 [mu] A.cm <-2 >, and the service life of the hepatic portal occlusion clamp is remarkably prolonged.

The invention belongs to the field of chemical power supply electrode materials, and discloses a Mg-Dy-Ho anode material of a magnesium-air battery as well as a preparation method and application of the Mg-Dy-Ho anode material. The anode material is prepared from the following raw materials in percentage by mass: 0.3-1.5% of intermediate alloy Mg-30% Dy, 0.3-1.5% of intermediate alloy Mg-30% Ho and the balance of high-purity magnesium metal. According to the invention, high-purity magnesium is taken as a matrix, rare earth elements dysprosium and holmium are compounded and added to realize microalloying, and the contradiction between activation and passivation of a magnesium anode is effectively balanced; a closed container is innovatively adopted in the smelting process to replace a crucible and a mold in the conventional smelting process, and ultrasonic treatment is carried out in the melt solidification process. According to the design, the dissolution uniformity and the corrosion resistance of the anode are remarkably improved, and experiments prove that the coexistence of Dy and Ho can synergistically reduce the corrosion current density, improve a discharge voltage platform and effectively inhibit hydrogen evolution side reaction, so that the utilization rate of the anode is improved to 61.1%.

The invention discloses a corrosion depth evaluation method and device, electronic equipment and a storage cut-off, and the method and device are applied to the electronic equipment and are used for evaluating the corrosion depth of galvanic corrosion at the joint of a magnesium alloy shell and a dissimilar metal part of a new energy vehicle. The method specifically comprises the steps that a change curve of galvanic corrosion current of a galvanic couple pair under a specific corrosion medium along with coupling time is constructed, and the galvanic couple pair is composed of magnesium alloy and dissimilar metal; calculating the contact time of the galvanic couple in contact with the corrosive medium; calculating according to the galvanic corrosion current and the exposed area of the galvanic pair to obtain the corrosion current density of the magnesium alloy shell; calculating the corrosion rate of the magnesium alloy according to the corrosion current density; and calculating the corrosion rate and the contact time based on the change curve to obtain an estimated value of the corrosion depth. It can be seen from the above content that according to the scheme, the estimated value of the corrosion depth can be obtained without long-time experiments, long experiment time is saved, and therefore the estimation efficiency is improved.

The invention discloses a salt-fog-resistant antioxidant high-entropy amorphous coating on the surface of a titanium alloy component and a preparation method of the salt-fog-resistant antioxidant high-entropy amorphous coating, and relates to the field of physical vapor deposition. A high-entropy alloy target material is used as a raw material, a high-power pulse magnetron sputtering and direct-current magnetron sputtering combined technology is adopted for preparation, and the high-entropy alloy target material comprises, by mass, 18%-25% of Ti, 20%-25% of V, 20%-25% of Cr, 20%-25% of Ni and 0.05%-0.2% of Si. The crystal structure of the coating is a single amorphous structure, the hardness is 8-12 GPa, the elasticity modulus is 120-180 GPa, and the coating is jointly composed of a transition layer and a coating body. Compared with a Ti6Al4V substrate, the coating has the advantages that the self-corrosion potential is corrected, and the self-corrosion current density is lower. The loss rate of the high-entropy amorphous coating is only 31% after the high-entropy amorphous coating is circularly corroded for 20 weeks in room-temperature salt mist (30 DEG C, 22 h) and high-temperature oxidation (550 DEG C, 2 h), the method is suitable for the titanium alloy component in the marine environment, and the corrosion resistance and high-temperature oxidation resistance of the titanium alloy component can be effectively improved.

The present application belongs to the technical field of surface treatment of metal base material and biomass particle composite electrodeposition, and discloses a preparation method of AZ91D magnesium alloy surface nickel base nano pearl powder composite electrodeposition layer. The cathode adopts a magnesium alloy sample after chemical pre-deposition, the anode adopts a nickel plate with mass fraction greater than 99%, both are connected to the negative pole and the positive pole of the pulse power source respectively, are immersed in the pre-configured electrodeposition liquid and placed in an ultrasonic generator for electrodeposition, and the ultrasonic generator works in a variable frequency mode. The formed deposition layer has smooth appearance, compact and uniform, the hardness is increased by 20 times to 22 times compared with the magnesium alloy substrate, increased by 1.3 times to 1.6 times compared with the pure nickel layer on the magnesium alloy surface electrodeposition, and the self-corrosion current density is decreased by 2 orders of magnitude to 3 orders of magnitude compared with the magnesium alloy substrate.

The invention belongs to the technical field of inorganic anticorrosive coatings, and discloses a low-temperature curing phosphate inorganic anticorrosive coating and a preparation method thereof. The coating is prepared from the following components in parts by mass: 80 to 120 parts of aluminum phosphate binder, 5 to 18 parts of ZnO coated SiO2 core-shell structure curing agent, 0.1 to 8 parts of functional modified lamellar filler and 10 to 30 parts of deionized water. The ZnO coated SiO2 core-shell structure is constructed, the release rate of Zn < 2 + > is delayed by utilizing the physical shielding effect of the SiO2 shell layer, the problem of implosion and cracking of a phosphate system in the low-temperature curing process is solved, and stable curing of the coating at the temperature of 80 DEG C is realized. Meanwhile, the modified mica powder is introduced, the compatibility of the filler and a matrix is enhanced through interface chemical bonding, and the compactness and adhesive force of the coating are remarkably improved. The self-corrosion current density of the coating is reduced to 10 <-8 > A / cm < 2 > order of magnitude, the adhesive force reaches grade 0, and the coating has excellent long-acting corrosion resistance.

The invention provides a high-performance and low-stress corrosion-sensitive aluminum alloy and a preparation method thereof, and the high-performance and low-stress corrosion-sensitive aluminum alloy comprises the following components in percentage by mass: 2.5-5.1% of Zn, 1.5-4.2% of Mg, 0.5-1.7% of Cu, 0.5-1.5% of Si, less than or equal to 0.03% of inevitable impurities and the balance of aluminum. The preparation method comprises the steps of smelting, dip angle cast rolling, homogenization treatment, multi-pass differential rolling reduction cold rolling, stepped solid solution and artificial aging treatment. According to the obtained high-performance low-stress corrosion-sensitive aluminum alloy, the width of a precipitation-free separation area is smaller than or equal to 120 nm, and the tensile strength is larger than or equal to 420 MPa; the self-corrosion current density is smaller than or equal to 1.5 microamperes / cm < 2 > after soaking in a 3.5 wt.% NaCl solution for 30-60 min, the corrosion rate is smaller than or equal to 0.08 mm / y after soaking is conducted for 14-30 days, a slow strain rate tensile test is conducted in the 3.5 wt.% NaCl solution at the rate of 4.9-5.1 * 10 <-5 > s <-1 >, and the stress corrosion sensitivity coefficient is smaller than or equal to 10%.

The invention discloses a layered ternary metal hydroxide anti-corrosion coating and a preparation method thereof.The preparation method comprises the following steps that firstly, a metal substrate is immersed in a mixed metal salt solution, M1M2M3-LDHs layered ternary metal hydroxide is prepared through in-situ growth, and divalent metal ions and trivalent metal ions are provided by the metal substrate and the mixed metal salt solution respectively; then, a surface modification technology is adopted, the obtained product is soaked in a mixed solution containing a corrosion inhibitor and a modifier, and the layered ternary metal hydroxide anti-corrosion coating M-LDHs-X is finally prepared through anion exchange and physical adsorption effects. The preparation method is simple in process, the obtained product is high in purity and good in performance, and cost reduction and efficiency improvement are achieved. From the perspective of a corrosion protection mechanism, the corrosion inhibitor and the modifier are introduced to endow the coating with good self-repairing and super-hydrophobic properties, and the corrosion inhibitor and the modifier synergistically play a role, so that the corrosion current density of the metal substrate is effectively reduced, and the corrosion resistance of the material is remarkably improved.

The application discloses a kind of 4,16 bis (m-methoxyphenyl) -[2,2] -p-xylene ring diatomic for preparing parylene coating resistant to electrochemical corrosion and its preparation method and application, specifically relates to a kind of 4,16 bis (m-methoxyphenyl) -[2,2] -p-xylene ring diatomic, its preparation method includes the following steps: S1, p-xylene ring diatomic is reacted with liquid bromine in the presence of catalyst, first solvent, and intermediate 1 is obtained;S2, intermediate 1 is reacted with 3-hydroxyphenylboronic acid in the presence of base salt, palladium catalyst and second solvent, and intermediate 2 is obtained;S3, intermediate 2 is reacted with methylating agent in the presence of base salt, third solvent, and the ring diatomic monomer is obtained.The phenyl parylene coating prepared from the above monomer shows excellent resistance to electrochemical corrosion, compared with the corrosion-resistant coating formed by the existing parylene monomer, not only the corrosion current density is low, and corrosion potential is high, has good application prospect in electronic product protection or medical instrument protection and the like.