38 results about "Anodic dissolution" patented technology

The invention discloses a circuit board wastewater heavy metal removal method and system, and the method comprises the steps: monitoring the concentration and valence distribution of heavy metal ions in circuit board wastewater in real time, and generating wastewater heavy metal form distribution characteristics in combination with oxidation-reduction potential and pH value; based on wastewater heavy metal form distribution characteristics, adjusting an oxidation-reduction environment to generate heavy metal ion enriched wastewater; the method comprises the following steps: introducing heavy metal ion enriched wastewater into an electric flocculation reactor, applying a periodic electric field through a programmable pulse power supply to dissolve an aluminum or iron anode to release a multi-core hydroxyl complex, and carrying out a co-precipitation reaction with heavy metal ions to generate a flocculating constituent suspension; and introducing the flocculating constituent suspension into a rotational flow clarification and separation device, realizing mud-water separation through centrifugal sedimentation and inclined plate separation, outputting supernate, discharging the supernate after reaching the standard, and recovering precipitated sludge rich in heavy metals. By utilizing the embodiment of the invention, efficient breaking and separation of the complex-state heavy metals can be realized, and good environmental benefits and resource values are achieved.

The invention belongs to the technical field of hydrogen sulfide stress corrosion resistance detection of oil well pipes, and particularly relates to a method for testing the influence of anodic dissolution in saturated hydrogen sulfide on stress corrosion fracture of an oil well pipe, which comprises the following steps: respectively carrying out slow strain rate tensile tests in a saturated hydrogen sulfide environment and a nitrogen environment to obtain a stress-strain curve of an oil well pipe sample; measuring a hydrogen permeation curve of the oil well pipe sample in the saturated hydrogen sulfide environment; carrying out fast and slow sweep potential polarization curve test and hydrogen permeation curve test on the oil well pipe, and carrying out hydrogen charging-slow stretching test on the oil well pipe under the cathode hydrogen charging potential corresponding to the steady-state hydrogen permeation current density; and according to the damage degree of the saturated hydrogen sulfide environment to the mechanical properties of the oil well pipe, the minimum influence degree of hydrogen in the saturated hydrogen sulfide environment to the stress corrosion fracture of the oil well pipe is determined by combining the damage degree of hydrogen separated out from the cathode reaction to the mechanical properties of the oil well pipe. The device has the advantages of simplicity in operation and accurate measurement result.

A near-atomic-scale electrolytic machining method based on an interface self-assembly biomask comprises the steps that firstly, hydroxylation pretreatment is conducted on the surface of an anode of a workpiece, then the surface of the anode is covered with an organic solvent phase containing phospholipid monomers, water-phase electrolyte drops are introduced, molecular self-assembly driving force at an oil-water-metal three-phase interface is utilized, and the surface of the anode of the workpiece is subjected to near-atomic-scale electrochemical machining. And rapidly forming a layer of ultrathin, continuous and stable support phospholipid bilayer mask on the surface of the workpiece in situ. Then, biological nanochannels are embedded in the biomimetic mask to construct a confinement ion transport path. And finally, a precise pulse electric field is applied, electrolyte ions are driven to be strictly limited in the nanometer channel and transmitted to the surface of the workpiece, local anodic dissolution is triggered, and therefore localized material removal of the nanometer scale or even the near-atomic scale is achieved. According to the method, the technical bottleneck that the high-quality phospholipid bilayer is difficult to prepare on the high-surface-energy metal surface is solved, and a new way is provided for ultra-precision electrolytic machining.

The invention relates to a phosphating method and device for a vehicle body, a vehicle and electronic equipment, and relates to the technical field of metal surface treatment.The method comprises the steps that the planned aluminum-steel surface area ratio of the vehicle body is obtained; determining the aluminum anode dissolution rate and the fluorinion consumption rate of the bath solution in the phosphating bath; wherein a vehicle body is placed in the phosphating tank; based on the planned aluminum steel surface area ratio, the aluminum anode dissolution rate and the fluorine ion consumption rate, the steady-state fluorine ion concentration of the bath solution is determined; and regulating and controlling the bath solution based on the steady-state fluorine ion concentration. Therefore, the fluorine ion concentration of the tank liquid in the phosphating tank can be controlled to maintain the expected fluorine ion concentration all the time, so that the phosphating quality of a vehicle body is improved.

The application discloses a copper electrolysis / electricity deposition device and a working method thereof in the technical field of crude copper electrolytic refining, which comprises a tank body, the tank body comprises a cathode cavity and an anode cavity, the cathode cavity and the anode cavity are arranged side by side and are communicated with each other, an electrolyte input device, the electrolyte input device is arranged in the cathode cavity, and the electrolyte input direction is from the cathode to the anode, an electrolyte output device, the electrolyte output device is arranged in the anode cavity, and the electrolyte output direction is from the anode to the cathode, cathode plates and anode plates can be arranged in the cathode cavity and the anode cavity respectively at intervals, and the cathode plates and the anode plates are connected with an electrolysis power source externally, the cathode cavity and the anode cavity adopt a cathode-anode different-tank structure, the purity of electrolyte in the cathode tank is high during the electrolysis process, the quality of cathode copper can be improved, the problem of short circuit caused by excessive dissolution of the anode plates and falling off of the anode plates during the electrolysis process can be avoided, the residual anode rate can be reduced, and silver ions generated by anode dissolution do not participate in cathode discharge, so that the silver recovery rate can be improved.

This invention relates to the field of laser processing technology and discloses a laser cutting process and apparatus for thick-walled tubes combined with electrochemical jet slag removal. The process includes: an automatic buffer material feeding and recovery mechanism pushes a high-temperature resistant ceramic-based inner liner tube into the inner cavity of a thick-walled tube as a buffer material for laser cutting; after cutting, the buffer material is removed, a physical sliding isolation sealing door is closed in conjunction with a flexible clearance pad, and a positive pressure air curtain blowing device is activated to seal the processing area; the thick-walled tube is connected to the anode of a power source, and the inner and outer jet nozzles are connected to the cathode, spraying high-pressure sodium nitrate passivation electrolyte into the residual slag area. The slag removal mechanism, which combines physical shielding at the slag source with electrochemical anodic dissolution and high-pressure liquid flow flushing, eliminates the contact stress caused by mechanical hard cutting and avoids the problem of micro-cracks at the tube wall wear ports; a spatial isolation protection mechanism prevents salt spray from eroding the optical lenses of the fiber laser cutting head and the machine tool transmission guide, completing a non-destructive slag removal operation.

The invention discloses an ion channel protein near-atomic scale confinement dissolution electrochemical machining method based on a bionic confinement interface. The method is characterized in that a bionic phospholipid bilayer mask is spread on a workpiece anode to shield a non-processing area, ion channel protein is embedded into the bionic phospholipid bilayer mask to serve as an electrolyte channel, and when the bionic phospholipid bilayer mask is powered on, the anode dissolution reaction is strictly limited in the ion channel protein channel. Millivolt-level picosecond-nanosecond pulse voltage or current is adopted on the time scale so that anode metal atoms can be removed one by one, electrolytic products are discharged in the modes of electrolyte adjustment, microcosmic acting force, micro vibration and the like so as to ensure sustainable generation of electrochemical reaction, and therefore near-atomic-scale electrolytic machining is achieved. The electrochemical machining technology and the biological field are fused in an interdisciplinary mode, the near-atomic-scale electrochemical dissolution reaction space is constructed, the capacity of electrochemical machining for removing materials in an ion form is approached, and near-atomic-scale electrochemical machining is achieved.

The invention particularly relates to a preparation method and device of high-purity copper with a rotary electrode, and belongs to the technical field of new material preparation. The device comprises at least one electrolysis unit, and the electrolysis unit is provided with a first electrode, a rotatable second electrode and a third electrode. The first electrode and the second electrode form an electrodeposition area, and the second electrode and the third electrode form an electrolysis area. According to the method, gradient voltage is applied to three electrodes, so that copper-containing electrolyte is firstly deposited on the surface of a rotating second electrode in an electrodeposition area for the first time; and then, the second electrode rotates to the electrolysis area, deposited copper on the surface of the second electrode serves as an anode to be dissolved, and secondary electrodeposition occurs on the third electrode. The lead anode impurity pollution can be effectively avoided from the source, and the technological process is simple, efficient, low in cost and suitable for large-scale production.

The utility model relates to a high-efficiency long-life sacrificial anode structure, which comprises flat iron and a sacrificial anode, an upper flat iron and a lower flat iron are arranged in the middle of the flat iron, the upper flat iron and the lower flat iron are embedded in the sacrificial anode, and the end parts of the upper flat iron and the lower flat iron are converged in the sacrificial anode and extend to the outer sides of the two ends of the sacrificial anode to form flat iron exposed ends. The sacrificial anode has the beneficial effects that the two pieces of flat iron are respectively arranged at different heights in the sacrificial anode, are embedded at different heights in the sacrificial anode and extend out of the bottoms of the two ends of the sacrificial anode, so that the fixing effect on the sacrificial anode is improved, and the sacrificial anode is not easy to fall off in the later period of dissolution; a certain number of holes are drilled in the two pieces of flat iron in the sacrificial anode, the hole diameter is determined according to the size of the flat iron, adhesion of the sacrificial anode is further improved, and the sacrificial anode can be effectively prevented from falling off.

The application discloses a method for preparing a titanium carbon oxide electrode by coating, and the method comprises the following steps: A. crushing and screening titanium carbon oxide, mixing the titanium carbon oxide with a pore-forming agent and a binder to obtain a mixture, and adding water into the mixture to prepare a slurry; B. coating the slurry on a graphite substrate by using a doctor blade; and C. drying and sintering the coated graphite substrate to obtain the titanium carbon oxide electrode. The application provides a method for preparing a titanium carbon oxide electrode by coating, the titanium carbon oxide electrode is prepared by coating and sintering the mixed slurry on a graphite substrate, the peeling problem of the electrode caused by gas scouring in an electrolysis process is avoided, the loose and porous structure formed by sintering makes the electrode have relatively high dissolving performance, the anode dissolving rate is increased from 50% to more than 80%, and the problem of low dissolving rate of the titanium carbon oxide anode in the electrode process is solved.

The invention belongs to the field of energy and metallurgy. Specifically, the invention discloses an electrolytic iron system based on multi-energy coupling and a surface topography multi-scale control method. A nano-micro-scale special surface microstructure is constructed on the cathode seed plate through a combined process of laser engraving, sand blasting treatment, anodic dissolution and photovoltaic current pre-coating. And meanwhile, magnetic field ultrasonic microwave multi-physical field enhanced ore phase reconstruction, acidolysis, anodic dissolution, photovoltaic current pre-coating, iron electrolysis and other procedures are adopted, and the reaction performance is improved. In the multi-scale control process of the surface appearance of the electrolytic iron, a multi-energy coupled clean energy supply system is adopted. According to the method, the non-uniform deposition problems such as cracking, blackening and dendritic crystals in the iron electrolysis process can be remarkably inhibited, and the current efficiency and the production stability are improved. The method is suitable for surface morphology regulation and control of pure iron prepared through large-scale continuous iron ore electrolysis, and has the advantages of being high in efficiency, low in energy consumption, free of pollution, ultralow in carbon dioxide emission and the like.

This disclosure provides a method for preparing a pre-grown film on the surface of a Zr-Ti-Ta alloy and the Zr-Ti-Ta alloy itself, relating to the field of alloy material preparation technology. The method includes: weighing composite Zr source powder, Ti powder, and Ta powder, and using them as raw materials for intermittent mechanical alloying; sequentially performing degassing and dehydrogenation, diffusion homogenization, and densification hot-pressing sintering; subjecting the α+β transition structure Zr-Ti-Ta alloy to phase stabilization heat treatment, cross-hot rolling, and recrystallization annealing; determining that the fine-grained single α-phase Zr-Ti-Ta alloy is within a constant potential pre-grown film window in the target medium; using the fine-grained single α-phase Zr-Ti-Ta alloy as a working electrode, immersing the working electrode in the target medium, defining the true potential of the working electrode relative to the reference electrode with a reference electrode, and ensuring that the true potential is within the constant potential pre-grown film window; and generating a dense barrier-type nanocomposite oxide pre-grown film containing ZrO2, TiO2, and Ta2O5 in situ on the surface of the fine-grained single α-phase Zr-Ti-Ta alloy. This disclosure can suppress localized anodic dissolution at crack tips and improve resistance to stress corrosion cracking.

A method for the anodic dissolution of nickel and cobalt metals in acids from recycled lithium ion batteries to their corresponding metal salts is disclosed. The anodic dissolution system comprises an anode and cathode compartment separated by an anion exchange membrane separator. The anode comprises the nickel or cobalt metal to be anodically dissolved while the cathode is a non-dissolvable cathode. In further embodiments, the anodic dissolution is performed in an acidic electrolyte, for example, sulfuric acid to so produce the corresponding metal sulfates. Where desired, the metal salt enriched anode solution can be passed through a membrane distillation unit to further concentrate the metal salt solution by removing water, which can be recycled in the anodic dissolution system. The nickel or cobalt salt solution can then be directly used in producing the metal oxides used in lithium ion and other batteries.

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 application discloses a magnesium alloy with high corrosion resistance and low stress corrosion tendency and a preparation method thereof, and belongs to the technical field of metal materials. The magnesium alloy has the following chemical components: 0.5-1.0% of aluminum, 1.0-4.0% of rare earth elements, and the balance of magnesium and inevitable impurities. The preparation method of the magnesium alloy comprises five steps of melting and casting, homogenization, solid solution treatment, multi-pass rolling and stress relief annealing. The application effectively controls the growth kinetics and growth morphology of the magnesium alloy surface hydroxide in the corrosive medium by reasonably designing the alloy components, increases the density of the magnesium alloy, reduces the penetration of chloride ions and hydrogen in the solution, and effectively reduces the anodic dissolution cracking and hydrogen embrittlement mechanical cracking.

The invention discloses an electronic electroplating wastewater treatment device with a heavy metal recovery function, and relates to the technical field of electroplating wastewater treatment.The electronic electroplating wastewater treatment device comprises a placement frame, sedimentation tanks and filtering tanks, the sedimentation tanks are symmetrically installed at the top of the placement frame, the filtering tanks are fixed to the positions, located at the bottoms of the sedimentation tanks on the single side, of the placement frame, and a first water pump is installed on the placement frame; a water inlet of the water pump I is communicated with the top side of the single-side settling tank through a pipeline; a water outlet of the water pump I is communicated with the bottom side of the filtering tank through a pipeline; through optimized arrangement of the ultrafiltration membrane cylinder and innovative design of a movable sealing cover backwashing mechanism, online directional backwashing and effective collection of a heavy metal concentrated solution are realized; a detection-treatment-recovery integrated solution is constructed by combining an anodic stripping voltammetry online detection system and an intelligent control platform, so that the heavy metal recovery rate and the water resource recycling efficiency are remarkably improved while continuous and stable operation of the system is ensured.

The invention discloses a method for plating indium on the surface of a copper back plate for recycling a target material. The method comprises the following steps: adjusting the pH value of a sodium chloride solution to 1-3.5 by using an acid solution to obtain an electrolyte; an inert cathode plate is used as a cathode, and a copper back plate is used as an anode; and controlling the electrolytic voltage to be 0.1-5V, carrying out an electrolytic reaction to obtain an indium-containing electrolyte and an indium layer deposited on the surface of the inert cathode plate, and finally recovering indium in the indium-containing electrolyte and the indium layer to obtain an indium hydroxide precipitate. By means of low-voltage selective electrolysis, efficient anode dissolution and cathode directional deposition of indium are achieved, physical mixing or chemical co-dissolution of copper and indium is avoided, the purity of recycled metal indium is high, corrosion to a copper backboard base body is small, operation is easy, automatic line production is facilitated, the recycling efficiency is high, the working voltage is low, energy consumption is small, cost is low, and toxic waste gas is avoided. The electrolyte can be recycled, the waste liquid amount is small, and pollution is avoided.

The invention belongs to the technical field of precious metal compound preparation, and particularly relates to a method for preparing cyanide-free gold plating solution gold sodium sulfite. A mixed solution of sodium sulfite and sodium chloride is used as anolyte, a sodium hydroxide solution is used as catholyte, and sodium sulfite in the anolyte is used as a complexing agent of gold ions and cooperates with sodium chloride to promote anode dissolution. According to the method, the toxicity risk of a traditional cyanide method is avoided, the reaction condition is mild, the product purity is high, no nitric oxide is generated in the process, no dangerous thanic acid gold intermediate is generated in the process, chloride ions can be effectively reduced, and a green and environment-friendly product can be produced.

The application discloses a kind of porous copper foil manufacturing equipment and method, belong to copper foil processing technical field.The equipment includes copper foil unwinding roller, guide roller assembly, electrolytic cell assembly, parallel roller assembly, winding roller and electrolytic unit.Electrolytic unit includes insoluble anode, cathode probe and fixing frame, cathode probe passes through insoluble anode but does not contact with it;Insoluble anode is connected with power supply positive pole, and cathode probe is connected with power supply negative pole.The method includes: non-porous copper foil passes through pretreatment unit, electrolytic cell and post-treatment unit, is immersed in electrolyte, voltage is applied between insoluble anode and cathode probe, and non-porous copper foil in the corresponding area of cathode probe tip is dissolved into hole by anodic dissolution due to bipolar electrode reaction.The application realizes that it can be controlled to be in the range of 0.1 μm~20 μm without contact with copper foil, equipment is simple, efficient, and high yield.

This invention discloses a green electrochemical polishing slurry and polishing method for additive manufacturing of stainless steel, belonging to the field of stainless steel surface treatment technology. The electrochemical polishing slurry comprises an acid, a polyol, glucose, sodium tungstate, and a corrosion inhibitor, wherein phosphoric acid is preferred, and polyaspartic acid is preferred. The polishing method includes surface pretreatment of the additively manufactured stainless steel workpiece, electrochemical polishing treatment, and post-polishing cleaning treatment. This invention utilizes the synergistic effect of sodium tungstate and polyaspartic acid to dynamically control the anodic dissolution interface during polishing, effectively suppressing over-polishing and pitting defects easily caused by the surface heterogeneity of additively manufactured stainless steel. Using the polishing slurry and method provided by this invention, the surface roughness of additively manufactured stainless steel can be significantly reduced, obtaining a bright and smooth high-quality surface. Furthermore, the polishing slurry is environmentally friendly and has significant industrial application value.

The invention discloses a method for preparing high-purity bismuth through electrolytic refining and an electrolysis system. The method comprises the following steps that an electrolyte is added into an electrolytic bath, an impurity removal agent is added into an impurity removal tank, the electrolytic bath and the impurity removal tank are connected through a guide pipe, and liquid in the electrolytic bath and liquid in the impurity removal tank circularly flow through a circulating pump for impurity removal; and the negative plate and the refined bismuth positive plate are oppositely inserted into the electrolyte, direct current is introduced for electrolysis, in the electrolysis process, the impurity removal process is continuously carried out, and high-purity bismuth is obtained on the negative plate. The electrolysis system is composed of an impurity removal agent liquid storage tank, an impurity removal tank, a filtering system and an electrolytic bath. The synchronous impurity removal process is integrated in the electrolysis process, impurities generated by anode dissolution can be removed in time, the product purity of high-purity bismuth is guaranteed, damage of the impurities to the performance of the electrolyte is reduced, the service life of the electrolyte is effectively prolonged, the consumable replacement cost in the production process is reduced, and collaborative improvement of quality improvement and cost reduction is achieved.

The invention discloses a method for preparing 6N indium by taking 4N indium as a raw material, which comprises the following steps: S1, preparing an anode plate and an indium sulfate electrolyte by taking 4N indium as a raw material; s2, taking the electrolyte in the step S1 and an anode plate as raw materials, placing the raw materials in a diaphragm electrolytic cell, and carrying out a pulse pre-electrolysis process; and S3, after the step S2 is finished, a negative plate of the diaphragm electrolytic cell is replaced, a bidirectional pulse electrolysis process is carried out, and 6N indium is prepared from the negative electrode. By adopting the anion exchange membrane, low-potential impurities and high-potential metal impurity ions dissolved in the anode can be only retained in the anode liquid and cannot penetrate through the anion exchange membrane to enter the cathode chamber, so that the impurity ions are prevented from being separated out at the cathode to influence the purity of indium. The invention innovatively provides a technology for preparing 6N indium through pulse preelectrolysis impurity removal-bidirectional pulse electrolysis by utilizing the characteristics of pulse electrolysis. The technology is advanced and reliable in process, low in cost and high in efficiency, and has great application potential and popularization value.

The invention discloses a recycled copper purification device and method based on an electrolytic method.The recycled copper purification device comprises an electrolytic bath, an electrolyte circulating system matched with the electrolytic bath and a conductive control unit, a bottom conductive copper bar is arranged at the bottom in the electrolytic bath, and a top conductive copper bar is arranged on the upper side of the electrolytic bath; limiting structures are arranged on the bottom conductive copper bar and the top conductive copper bar so that anode baskets and cathode plates can be alternately installed at intervals, and each anode basket comprises a frame body with an opening in the upper end and two hollowed-out sides and filter screens laid at the hollowed-out positions of the two sides. And the electrolytic bath is externally connected with a compressed air pipe so as to introduce compressed air into the electrolytic bath. According to the method, the problems that anode slime is difficult to clean, an anode is not fully dissolved, an electrolyte is not uniformly distributed and the purity of cathode copper is insufficient in the copper recovery process through an existing electrolytic method can be solved.

The invention belongs to the technical field of oil well pipe stress corrosion performance detection, and particularly relates to a method for testing the influence of hydrogen and anode dissolution coupling on oil well pipe stress corrosion fracture, which comprises the following steps: respectively carrying out slow strain rate tensile tests in a hydrogen sulfide environment and a nitrogen environment to determine the damage degree of the hydrogen sulfide environment to the mechanical properties of an oil well pipe; carrying out potentiodynamic polarization curve testing on the oil well pipe by adopting slow-rate scanning and fast-rate scanning respectively, wherein the space between corrosion potentials Vs-Vf is the potential interval of the hydrogen and anode dissolution coupling effect; respectively carrying out constant potential slow stretching test on the oil well pipe in an acid environment; according to the damage degree of the hydrogen sulfide environment to the mechanical property of the oil well pipe, the influence degree of the coupling effect of anode dissolution and hydrogen induced cracking in the hydrogen sulfide environment to the stress corrosion fracture of the oil well pipe is determined by combining the damage degrees of the anode dissolution mechanism and the hydrogen induced cracking mechanism to the mechanical property of the oil well pipe. The device has the advantages of simplicity in operation and accurate measurement result.

The present invention relates to a method for evaluating the effect of hydrogen and anodic dissolution coupling on stress corrosion cracking of pipeline steel, comprising: (1) performing slow strain rate tensile tests in an acidic environment and a nitrogen environment respectively to determine the degree of damage caused by the acidic environment to the mechanical properties of the pipeline steel sample; (2) performing potentiodynamic polarization curve tests on the pipeline steel sample using slow rate scanning and fast rate scanning respectively to determine the potential range of the stress corrosion sensitive area; (3) performing constant potential slow tensile tests on the pipeline steel sample in an acidic environment at the starting potential of anodic dissolution alone and the starting potential of hydrogen-induced cracking alone to determine the degree of damage caused by anodic dissolution and hydrogen-induced cracking to the mechanical properties of the pipeline steel; (4) determining the degree of influence of anodic dissolution and hydrogen coupling on the stress corrosion cracking of the pipeline steel sample in the acidic environment and the contribution ratio of stress corrosion cracking. The present invention can accurately and quickly evaluate the stress corrosion resistance of pipeline steel.

The application discloses an electrolytic machining stray corrosion inhibition method based on a zirconium electrode and a bipolar pulse, and comprises the following steps: adopting metal zirconium as a tool electrode; during machining, a bipolar pulse voltage is applied between the tool electrode and a workpiece; through polarity switching of the bipolar pulse voltage, a surface oxide layer of the zirconium electrode is driven to spontaneously form a structure partition with an end face conducting and a side wall insulating in a positive pulse machining stage, so as to inhibit stray corrosion. The application utilizes the synergistic effect of bipolar pulse alternating polarization and the passivation characteristics of the zirconium electrode, effectively shields the side electric field without a side wall insulating coating, significantly improves machining precision, and fundamentally eliminates the problem of anode dissolution loss of the tool electrode caused by a negative pulse in traditional bipolar pulse electrolytic machining.

The invention relates to the field of nanometer materials, in particular to an iron oxide nanosheet and a preparation method and application thereof.The preparation method comprises the following steps that an iron sheet is connected with the positive electrode of a power source, an inert electrode is connected with the negative electrode of the power source, and the iron sheet and the inert electrode are placed in an electrolytic bath containing an electrolyte solution; and carrying out electrolytic reaction under an oxygen condition to obtain the iron oxide nanosheet, the electrolyte solution contains sodium chloride and boric acid, and the circulating potential of the electrolytic reaction is 0.2-0.9 V. The circulation potential of the electrolytic reaction ranges from 0.2 V to 0.9 V, the anode dissolution potential (0.447 V) of Fe-> Fe < 2 + > is covered, and continuous growth of a passive film is destroyed through periodic voltage disturbance. In the process, the dissolved Fe < 2 + > and dissolved oxygen in the solution are subjected to oxidation reaction, and finally the iron oxide nanosheet is formed.

The invention discloses a hard and brittle wafer lossless thinning method based on internal and external cooperative laser modification and electrochemical stripping, and belongs to the technical field of semiconductor manufacturing. The method comprises the following steps: (1) scanning in a predetermined depth in a wafer by adopting a first beam of ultrafast laser to form a continuous internal modified layer so as to define the final stripping thickness; (2) scanning and ablating the back surface of the wafer by adopting a second beam of laser to form a micro-channel array which is directly communicated with the internal modification layer; (3) placing the wafer as an anode in an electrochemical device, and performing selective electrochemical anode dissolution on the internal modified layer by using the micro-channel array as a channel for efficiently permeating electrolyte and rapidly discharging reaction products, so that the main body layer of the wafer with the preset thickness is nondestructively stripped from the matrix; and (4) carrying out ultra-precision polishing on the new surface of the stripped wafer main body. Through internal and external synergistic modification, an efficient mass transfer channel is constructed, and the problems of efficiency and uniformity in large-area internal stripping are innovatively solved.

The invention relates to the field of electrochemical corrosion and protection of materials, in particular to a method for predicting the electrochemical corrosion behavior of an alloy in an acid solution based on a first principle. The method comprises the following steps: (1) constructing a surface model of the alloy through surface cutting and cell expansion; (2) on the basis of the first principle density functional theory, the activation energy of anode dissolution, the adsorption free energy of hydrogen, the surface work function and the Volta contact potential difference are calculated through a surface model; and (3) substituting the parameters into a Butler-Volmer equation, and drawing an anode dissolution and cathode hydrogen evolution curve, so as to predict the electrochemical corrosion behavior of the alloy in an acid solution. According to the method, the activation energy of anode dissolution is represented in the mode that surface atoms are slowly lifted up to obtain the total energy difference of the surface atoms, an original corrosion model is not only suitable for simple substances, but also can be used for materials such as alloys, and prediction of corrosion behaviors of the simple substances and the alloys in an acid solution is achieved in combination with an existing cathode hydrogen evolution reaction formula.

This invention belongs to the field of chemical power source electrode materials, and discloses a Mg-Dy-Ho anode material for magnesium-air batteries, its preparation method, and its application. The anode material is prepared from the following raw materials by mass percentage: 0.3-1.5% Mg-30%Dy master alloy, 0.3-1.5% Mg-30%Ho master alloy, with the balance being high-purity metallic magnesium. This invention uses high-purity magnesium as the matrix, and incorporates rare earth elements dysprosium and holmium to achieve microalloying, effectively balancing the activation and passivation contradictions of the magnesium anode. It also innovatively uses a sealed container instead of the crucible and mold in the conventional melting process, and performs ultrasonic treatment during melt solidification. This design significantly improves the uniformity of anode dissolution and corrosion resistance. Experiments have shown that the coexistence of Dy and Ho can synergistically reduce the corrosion current density, increase the discharge voltage plateau, and effectively suppress hydrogen evolution side reactions, increasing the anode utilization rate to 61.1%.