A material deposition method controlled by electromagnetic field

Abstract

This invention provides a material deposition method controlled by an electromagnetic field, belonging to the field of material surface treatment technology. The method includes preparing a precursor electrolyte containing a nickel source, an iron source, a tungsten source, sodium citrate, and an additive A. The raw materials for preparing additive A include hydrophilic fumed silica, sodium perfluorononenoxybenzenesulfonate, sodium polyepoxysuccinate, and graphene powder. During deposition, a dynamic electromagnetic field is applied to the pretreated substrate, which is a combination of a static bias magnetic field, a low-frequency alternating magnetic field, and a high-frequency pulsed electric field in a preset time sequence, and the current density is simultaneously controlled. Through the synergistic effect and dynamic evolution of multiple physical fields, ion migration, interfacial reaction, and in-situ generation of nano-reinforcing phases in the electrolyte are guided, and a composite coating is prepared in one step. This method solves the problems of high internal stress, poor adhesion, and uneven structure of coatings in traditional technologies. The prepared coating exhibits excellent microhardness, adhesion, wear rate, corrosion resistance, and internal stress control.

Description

Technical Field

[0001] This invention relates to the field of material surface treatment technology, and in particular to a material deposition method using electromagnetic field control. Background Technology

[0002] Materials deposition technology, especially electromagnetic field-assisted deposition technology, plays a crucial role in modern high-end manufacturing. Techniques such as magnetron sputtering, arc ion plating, and electrodeposition have been widely used in the preparation of wear-resistant, corrosion-resistant, and functional coatings. However, in the field of physical vapor deposition, although magnetron sputtering technology has a high deposition rate, its inherent racetrack-like etching mode results in a target utilization rate that is usually less than 40%. Furthermore, when depositing insulating materials, target poisoning is prone to occur, leading to arc discharge and film contamination. To solve the problem of target poisoning, medium-frequency AC magnetron sputtering technology has been proposed, but it does not change the static nature of the magnetic field distribution, limiting its ability to finely control the coating structure. Arc ion plating technology has long been plagued by large particle contamination, and droplet sputtering leads to a decrease in coating density. Although subsequent methods such as magnetic field filtration have been developed, they often come at the cost of sacrificing deposition efficiency and uniformity. Current technological improvements largely focus on the mechanical adjustment of external magnetic fields, such as expanding the etched area by rotating permanent magnets. However, these methods are ineffective for precise control of plasma transport and suppressing the root causes of large particles. In the field of liquid-phase electrochemical deposition, magnetic field-assisted electrodeposition (MFED) utilizes magnetohydrodynamic effects to improve mass transfer and refine grain size. However, the industrialization of this technology faces significant challenges, including poor process repeatability. Small fluctuations in magnetic field parameters can drive complex micro-convection through Lorentz forces, amplifying uncertainties in the morphology and properties of the deposited layer. Achieving a uniform and stable magnetic field is costly when scaling up from laboratory to industrial scale. More importantly, existing research largely treats electromagnetic fields as external tools to improve macroscopic process conditions (such as stirring and mass transfer), severely neglecting the intrinsic and dynamic coupling mechanism between the external field and the microscopic dynamic processes involved in the deposition process itself, such as interfacial adsorption, charge transfer, atomic stacking, and in-situ chemical reactions. Therefore, developing a novel material deposition method controlled by electromagnetic fields has become an urgent need for the industry. Summary of the Invention

[0003] The purpose of this invention is to provide a material deposition method controlled by an electromagnetic field, which addresses the problems existing in the prior art, such as low target utilization, severe large particle contamination, high coating internal stress, poor adhesion, poor process stability and repeatability, and the inability to achieve uniform dispersion of the reinforcing phase at the nanoscale and controllable construction of compositional structure gradients. These problems collectively result in the difficulty in synergistically improving the overall performance of the coating, limiting high-end applications, and preventing deep integration and dynamic synergistic control. The specific technical solution of this invention is as follows: This invention provides a material deposition method using electromagnetic field control, comprising the following steps: S1. Preparation of auxiliary agent A; S2. Pre-treat the metal substrate; S3. Prepare the precursor electrolyte. The raw materials for preparing the precursor electrolyte include, by weight: 48-52 parts nickel sulfate hexahydrate, 6.3-6.8 parts ferrous aminosulfonate, 0.9-1.1 parts ammonium metatungstate, 11.5-12.5 parts sodium citrate, 29-31 parts sodium sulfate, 3.8-4.2 parts sodium bisulfate, 0.18-0.22 parts sodium saccharin, 0.08-0.12 parts sodium dodecyl sulfate, 1000 parts deionized water, and 4-5 parts auxiliary agent A. S4. Electromagnetic field controlled deposition: The pretreated metal substrate is placed into the deposition tank as the cathode, the precursor electrolyte is injected, electrodeposition is carried out in constant current mode, and a composite electromagnetic field is applied. The deposition process includes an initial deposition stage, a main deposition stage and a gradient deposition stage performed sequentially.

[0004] Furthermore, during the initial deposition stage, a static bias magnetic field and a low-frequency alternating magnetic field are applied, while the high-frequency pulsed electric field is not activated. During the main deposition stage, a high-frequency pulsed electric field is activated, and the strength of the static bias magnetic field and the frequency and field strength of the low-frequency alternating magnetic field are increased. During the gradient deposition stage, the deposition current density and the static bias magnetic field strength are reduced, while the frequency of the low-frequency alternating magnetic field is increased.

[0005] Furthermore, the raw materials for preparing additive A, by weight, include: 3.8-4.2 parts of hydrophilic fumed silica, 0.9-1.1 parts of sodium perfluorononenoxybenzenesulfonate, 8.5-9.5 parts of sodium polyepoxysuccinate, 0.45-0.55 parts of graphene powder, 87-89 parts of deionized water, and 5.5-6.5 parts of glycerol.

[0006] Further, the preparation method of additive A includes: dispersing hydrophilic fumed silica in a portion of deionized water and stirring at 35°C and a first stirring speed for 30-60 minutes; adding sodium polyoxysuccinate and increasing the stirring speed to a second stirring speed for 20-30 minutes; adjusting the stirring speed back to the first stirring speed and adding an aqueous solution of sodium perfluorononenoxybenzenesulfonate, increasing the stirring speed to a second stirring speed for 20 minutes to obtain mixture A; premixing graphene powder with glycerol for 5-15 minutes and then adding it to mixture A and stirring for 20-40 minutes; subjecting the stirred material to circulation homogenization; subjecting the homogenized material to vacuum stirring and degassing, and filtering to obtain additive A; The first speed is 400 rpm, and the second speed is 1200 rpm.

[0007] Furthermore, the conditions for the circulating homogenization process are as follows: under circulating water cooling, two-stage pressure is used, with the first stage pressure being 30-50 MPa and the second stage pressure being 5-10 MPa, and the process is repeated 1-5 times; the conditions for vacuum stirring and degassing are: vacuum degree -0.08 to -0.095 MPa, rotation speed 30 rpm, and degassing time 30-60 minutes.

[0008] Further, step S3 includes stirring deionized water, nickel sulfate hexahydrate, ferrous aminosulfonate, ammonium metatungstate, sodium citrate, sodium sulfate, and sodium bisulfate for 10-30 minutes at 35-40°C and 300 rpm; adding sodium saccharin and sodium dodecyl sulfate and stirring for 10-30 minutes; adding auxiliary agent A at 45-50°C and stirring at 500 rpm for 20-60 minutes, and adjusting the pH value to 4.0.

[0009] Furthermore, during the initial deposition stage, the static bias magnetic field strength is 0.1-0.15 Tesla, and the low-frequency alternating magnetic field parameters are 5-10 Hz with a field strength of 0.03-0.05 Tesla. During the main deposition stage, the static bias magnetic field strength is linearly increased to 0.2-0.25 Tesla within 5 minutes, the frequency of the low-frequency alternating magnetic field is increased to 10-20 Hz, and the field strength is increased to 0.08-0.1 Tesla. A high-frequency pulsed electric field is also activated, wherein the pulse frequency of the high-frequency pulsed electric field is 800-1000 Hz, the pulse width is 50-100 microseconds, and the peak field strength is 3000-5000 V / m. The main deposition stage lasts for 60-120 minutes.

[0010] Furthermore, the gradient deposition stage takes place in the last 10-30 minutes after the main deposition stage, linearly reducing the deposition current density from 2 amperes / dm² to 1 ampere / dm², while linearly reducing the static bias magnetic field strength from 0.2-0.25 Tesla to 0.08-0.1 Tesla, and linearly increasing the frequency of the low-frequency alternating magnetic field from 10-20 Hz to 30-50 Hz.

[0011] Further, step S2 pretreatment of the metal substrate includes: sequential polishing, alkaline degreasing, ultrasonic cleaning, electrochemical activation, water washing, dehydration and drying; the alkaline degreasing solution contains 30 g / L sodium hydroxide, 25 g / L sodium carbonate, 15 g / L sodium phosphate and 5 g / L sodium silicate; electrochemical activation is carried out in a 10% (v / v) dilute sulfuric acid solution, with the substrate as the cathode, the lead plate as the anode, the current density as 5 amperes / dm², and the activation time as 30 seconds.

[0012] Furthermore, in step S4, a pure nickel plate is used as the anode, and the ratio of anode to cathode area is 1:2. During the deposition process, the precursor electrolyte is magnetically stirred at a stirring rate of 150 rpm, and the water bath temperature is kept stable at 45-50℃.

[0013] The beneficial effects of this invention are as follows: The material deposition method provided by this invention achieves the following effects through the internal synergy: the physical stabilization effect of the internal fumed silica in the special additive A, the persistent wetting and adsorption effect of the perfluorinated surfactant, the stress buffering and interface regulation effect of sodium polyepoxysuccinate, and the current homogenization effect of the graphene micronetwork. This is further enhanced by the external synergy of components such as the nickel / iron main salt, tungsten / carbon reaction source, citric acid complexing agent, and traditional additive sodium saccharin in the precursor electrolyte. This is achieved within a dynamic physical field environment where a specific static bias magnetic field, a low-frequency alternating magnetic field, and a high-frequency pulsed electric field are coupled in a preset time sequence. Together, they achieve a multi-level synergistic effect of "field-agent-reaction". This synergistic effect is specifically manifested in the composite electromagnetic field guiding the directional migration and energy distribution of ions, the auxiliary agent A ensuring the stability and uniformity of the reaction interface, and the electrolyte components providing the material basis for the generation of nanocomposite structures. The deep integration of these three elements, through technical aspects such as in-situ uniform dispersion of nano-reinforcing phases, precise control of coating internal stress, and integrated construction of dense gradient structures, enables the resulting coating to achieve comprehensive synergistic improvement in key properties such as microhardness, bonding strength, wear resistance, and corrosion resistance. Moreover, the process is stable and has good repeatability. Specifically, the working principle of this invention is based on the regulation of the electrode process by electrochemical deposition, magnetohydrodynamics, and pulsed electric fields. First, the applied static bias magnetic field generates Lorentz force on charged ions in the electrolyte, triggering a magnetohydrodynamic effect, thereby enhancing the mass transfer process near the interface and making the ion supply more uniform. Simultaneously, the low-frequency alternating magnetic field induces eddy currents in the solution, generating periodic micro-stirring, which effectively disrupts the diffusion layer, reduces concentration polarization, and may slightly perturb the behavior of ferromagnetic or paramagnetic ions, affecting their deposition orientation. The introduction of a high-frequency pulsed electric field, through its instantaneous high field strength, periodically and violently reconstructs the double-layer structure of the cathode / solution interface, greatly increasing the overpotential and driving force of the electrochemical reaction. This not only significantly promotes the reduction deposition rate of metal ions, but more importantly, provides the necessary high-energy environment for the in-situ chemical reaction between active carbon atoms decomposed from citrate and tungstate ions on the cathode surface to generate nano-tungsten carbide, which is key to achieving uniform in-situ synthesis of nanophases. In additive A, hydrophilic silica forms a steric hindrance to stabilize the electrolyte; perfluorinated surfactants ensure that the cathode surface remains superwetted under complex electromagnetic fields, creating an ideal interface for uniform deposition; the adsorption of sodium polyepoxysuccinate buffers the stress during the stacking of deposited atoms; and the graphene micronetwork helps to balance the current density distribution on the cathode surface. Finally, by programming the linear evolution of the above three electromagnetic field intensities, frequencies, and current densities throughout the entire deposition cycle, the spatiotemporal fine control of deposition kinetics and thermodynamics was achieved, thereby guiding the coating to form a gradient functional material with continuously changing composition and structure from the inside out, thus optimizing the coating's structure and properties. Detailed Implementation

[0014] The technical solutions in the embodiments of this application are described clearly and completely below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0015] The sodium perfluorononenoxybenzenesulfonate involved in this invention is F901 from Shanghai Futian Technology Co., Ltd., the sodium polyepoxysuccinate is purchased from Shandong Taihe Water Treatment Technology Co., Ltd., the hydrophilic fumed silica is CAB-O-SIL® EH-5 from Cabot Corporation, and the graphene powder is CASYUEDA-G10 from Zhongke Yueda (Shanghai) Materials Technology Co., Ltd.

[0016] Example 1 This embodiment provides a material deposition method using electromagnetic field control, comprising a precursor electrolyte comprising, by weight: 50 parts nickel sulfate hexahydrate, 6.5 parts ferrous aminosulfonate, 1 part ammonium metatungstate, 12 parts sodium citrate, 30 parts sodium sulfate, 4 parts sodium bisulfate, 0.2 parts sodium saccharin, 0.1 parts sodium dodecyl sulfate, 1000 parts deionized water, and 5 parts additive A.

[0017] The raw materials for preparing additive A, by weight, include: 4 parts hydrophilic fumed silica, 1 part sodium perfluorononenoxybenzenesulfonate, 10 parts sodium polyepoxysuccinate, 0.5 parts graphene powder, 88 parts deionized water, and 6 parts glycerol.

[0018] This embodiment also provides a material deposition method controlled by an electromagnetic field, the method comprising the following steps by weight: Step 1: Preparation of Additive A: Add 79.2 parts of deionized water and 4 parts of hydrophilic fumed silica at 35℃, stir at 400 rpm for 60 minutes, add 10 parts of sodium polyoxysuccinate, stir at 1200 rpm for 30 minutes, then adjust the speed back to 400 rpm and slowly pump in 1 part of sodium perfluorononenoxybenzenesulfonate aqueous solution (prepared as a 10% solution with 8.8 parts of deionized water) at a rate of 0.1 parts / minute. After pumping, increase the speed to 1200 rpm and stir for 20 minutes to obtain mixture A. 0.5 parts of graphene powder and 6 parts of glycerol were premixed at 800 rpm for 15 minutes. The mixture was then added to mixture A and stirred for 40 minutes. The mixture was cyclically homogenized 5 times under circulating water cooling at 25°C and pressures of 50 MPa (first stage) and 10 MPa (second stage). The mixture was then stirred and degassed at -0.095 MPa and 30 rpm for 60 minutes. The mixture was then filtered using a polypropylene bag filter with a pore size of 5 micrometers at 0.1 MPa to obtain additive A.

[0019] Step 2, Substrate Pretreatment: Take a 304 stainless steel substrate with dimensions of 50 mm × 100 mm × 1 mm, and polish the surface sequentially using 800 grit, 1200 grit, and 2000 grit silicon carbide wet sandpaper. Immerse the polished substrate in an alkaline degreasing solution at 65°C (containing 30 g / L sodium hydroxide, 25 g / L sodium carbonate, 15 g / L sodium phosphate, and 5 g / L sodium silicate) for 15 minutes. Then, ultrasonically clean it with 60°C deionized water for 5 minutes. In a 10% (v / v) dilute sulfuric acid solution, with the substrate as the cathode and a lead plate as the anode, apply a current density of 5 amperes / dm² for 30 seconds to activate it. Rinse it with flowing deionized water for 30 seconds, immerse it in anhydrous ethanol for dehydration, and dry it in an 80°C forced-air drying oven for 10 minutes. After drying, transfer it to the deposition station.

[0020] Step 3: Prepare the precursor electrolyte: Add 1000 parts deionized water, 50 parts nickel sulfate hexahydrate, 6.5 parts ferrous aminosulfonate, 1 part ammonium metatungstate, 12 parts sodium citrate, 30 parts sodium sulfate, and 4 parts sodium bisulfate. Stir at 40°C and 300 rpm for 30 minutes. Add 0.2 parts sodium saccharin and 0.1 parts sodium dodecyl sulfate, and stir for 30 minutes. Add 5 parts of the auxiliary agent A prepared in Step 1 at 50°C, increase the stirring speed to 500 rpm, and stir for 60 minutes. Adjust the pH of the electrolyte to 4.0 to obtain the precursor electrolyte for use.

[0021] Step 4, Electromagnetic field controlled deposition: Install the pretreated substrate from Step 2 onto the cathode rod of the deposition tank, place two pure nickel plates as anodes on both sides, with an anode-cathode area ratio of 1:2, inject the electrolyte prepared in Step 3 into the deposition tank, turn on the magnetic stirring, set the speed to 150 rpm, and stabilize the water bath temperature at 50℃. Turn on the DC power supply, using constant current mode, and set the current density to 2 amperes / dm². Simultaneously activate the electromagnetic field system: set the static bias magnetic field strength to 0.15 Tesla, the low-frequency alternating magnetic field to 10 Hz and 0.05 Tesla, and temporarily disable the high-frequency pulse electric field. This initial deposition stage lasts for 10 minutes. Entering the main deposition stage, while maintaining a constant current density, the static bias magnetic field strength is linearly increased to 0.25 Tesla within 5 minutes, the low-frequency alternating magnetic field frequency is simultaneously increased to 20 Hz and the peak field strength is increased to 0.1 Tesla, and a high-frequency pulsed electric field is activated (pulse frequency 1000 Hz, pulse width 100 microseconds, peak field strength 5000 V / m). This stage lasts for 120 minutes. Entering the gradient deposition stage, in the last 30 minutes, the current density is linearly reduced from 2 A / dm² to 1 A / dm². Simultaneously, the static bias magnetic field strength is reduced from 0.25 Tesla to 0.1 Tesla, while the low-frequency alternating magnetic field frequency is increased from 20 Hz to 50 Hz. The high-frequency pulsed electric field parameters remain unchanged. After deposition, disconnect all power and electromagnetic fields. Remove the coated substrate, rinse the surface with running deionized water, immerse it in a 1% (mass fraction) ammonia solution for 10 seconds to neutralize, remove it and rinse it again with deionized water until the pH of the effluent is 7.0, and finally dry it in an 80°C forced-air drying oven for 5 minutes to complete the deposition.

[0022] Example 2 This embodiment provides a material deposition method using electromagnetic field control, comprising a precursor electrolyte comprising, by weight: 48 parts nickel sulfate hexahydrate, 6.3 parts ferrous aminosulfonate, 0.9 parts ammonium metatungstate, 11.5 parts sodium citrate, 31 parts sodium sulfate, 3.8 parts sodium bisulfate, 0.18 parts sodium saccharin, 0.12 parts sodium dodecyl sulfate, 1000 parts deionized water, and 4.5 parts additive A.

[0023] The raw materials for preparing additive A, by weight, include: 3.8 parts hydrophilic fumed silica, 0.9 parts sodium perfluorononenoxybenzenesulfonate, 9.5 parts sodium polyepoxysuccinate, 0.45 parts graphene powder, 89 parts deionized water, and 5.5 parts glycerol.

[0024] This embodiment also provides a material deposition method controlled by an electromagnetic field, the method comprising the following steps by weight: Step 1: Preparation of Additive A: Add 80.1 parts of deionized water and 3.8 parts of hydrophilic fumed silica at 35℃, stir at 400 rpm for 60 minutes, add 9.5 parts of sodium polyoxysuccinate, stir at 1200 rpm for 30 minutes, then adjust the speed back to 400 rpm and slowly pump in 0.9 parts of sodium perfluorononenoxybenzenesulfonate aqueous solution (prepared as a 10% solution with 8.9 parts of deionized water) at a rate of 0.1 parts / minute. After pumping, increase the speed to 1200 rpm and stir for 20 minutes to obtain mixture A. 0.45 parts of graphene powder and 5.5 parts of glycerol were premixed at 800 rpm for 15 minutes. The mixture was then added to mixture A and stirred for 30 minutes. The mixture was cyclically homogenized three times under circulating water cooling at 25°C and pressures of 50 MPa (first stage) and 10 MPa (second stage). The mixture was then stirred and degassed at -0.095 MPa and 30 rpm for 60 minutes. The mixture was then filtered using a polypropylene bag filter with a pore size of 5 micrometers at 0.1 MPa to obtain additive A.

[0025] Step 2, Substrate Pretreatment: Take a 304 stainless steel substrate with dimensions of 50 mm × 100 mm × 1 mm, and polish the surface sequentially using 800 grit, 1200 grit, and 2000 grit silicon carbide wet sandpaper. Immerse the polished substrate in an alkaline degreasing solution at 65°C (containing 30 g / L sodium hydroxide, 25 g / L sodium carbonate, 15 g / L sodium phosphate, and 5 g / L sodium silicate) for 15 minutes. Then, ultrasonically clean it with 60°C deionized water for 5 minutes. In a 10% (v / v) dilute sulfuric acid solution, with the substrate as the cathode and a lead plate as the anode, apply a current density of 5 amperes / dm² for 30 seconds to activate it. Rinse it with flowing deionized water for 30 seconds, immerse it in anhydrous ethanol for dehydration, and dry it in an 80°C forced-air drying oven for 10 minutes. After drying, transfer it to the deposition station.

[0026] Step 3: Prepare the precursor electrolyte: Add 1000 parts deionized water, 48 parts nickel sulfate hexahydrate, 6.3 parts ferrous aminosulfonate, 0.9 parts ammonium metatungstate, 11.5 parts sodium citrate, 31 parts sodium sulfate, and 3.8 parts sodium bisulfate. Stir at 40°C and 300 rpm for 20 minutes. Add 0.18 parts sodium saccharin and 0.12 parts sodium dodecyl sulfate, and stir for 20 minutes. Add 4.5 parts of the auxiliary agent A prepared in Step 1 at 50°C, increase the stirring speed to 500 rpm, and stir for 30 minutes. Adjust the pH of the electrolyte to 4.0 to obtain the precursor electrolyte for use.

[0027] Step 4, Electromagnetic field controlled deposition: Install the pretreated substrate from Step 2 onto the cathode rod of the deposition tank, place two pure nickel plates as anodes on both sides, with an anode-cathode area ratio of 1:2, inject the electrolyte prepared in Step 3 into the deposition tank, turn on the magnetic stirring, set the speed to 150 rpm, and stabilize the water bath temperature at 50℃±0.5℃. Turn on the DC power supply, using constant current mode, and set the current density to 2 amperes / dm². Simultaneously activate the electromagnetic field system: set the static bias magnetic field strength to 0.15 Tesla, the low-frequency alternating magnetic field to 10 Hz and 0.05 Tesla, and temporarily disable the high-frequency pulse electric field. This initial deposition stage lasts for 10 minutes. Entering the main deposition stage, while keeping the current density constant, the static bias magnetic field strength is linearly increased to 0.25 Tesla within 5 minutes, the low-frequency alternating magnetic field frequency is synchronously increased to 20 Hz and the peak field strength is increased to 0.1 Tesla, and the high-frequency pulsed electric field (pulse frequency 1000 Hz, pulse width 100 microseconds, peak field strength 5000 V / m) is activated. This stage lasts for 90 minutes. Entering the gradient deposition stage, in the final 20 minutes, the current density is linearly reduced from 2 A / dm² to 1 A / dm². Simultaneously, the static bias magnetic field strength is reduced from 0.25 Tesla to 0.1 Tesla, while the low-frequency alternating magnetic field frequency is increased from 20 Hz to 50 Hz. The high-frequency pulsed electric field parameters remain unchanged. After deposition, disconnect all power and electromagnetic fields. Remove the coated substrate, rinse the surface with running deionized water, immerse it in a 1% (mass fraction) ammonia solution for 10 seconds to neutralize, remove it and rinse again with deionized water until the pH of the effluent is 7.5, and finally dry it in an 80°C forced-air drying oven for 5 minutes to complete the deposition.

[0028] Example 3 This embodiment provides a material deposition method using electromagnetic field control, comprising a precursor electrolyte comprising, by weight: 52 parts nickel sulfate hexahydrate, 6.8 parts ferrous aminosulfonate, 1.1 parts ammonium metatungstate, 12.5 parts sodium citrate, 29 parts sodium sulfate, 4.2 parts sodium bisulfate, 0.22 parts sodium saccharin, 0.08 parts sodium dodecyl sulfate, 1000 parts deionized water, and 4 parts additive A.

[0029] The raw materials for preparing additive A, by weight, include: 4.2 parts hydrophilic fumed silica, 1.1 parts sodium perfluorononenoxybenzenesulfonate, 8.5 parts sodium polyepoxysuccinate, 0.55 parts graphene powder, 87 parts deionized water, and 6.5 parts glycerol.

[0030] This embodiment also provides a material deposition method controlled by an electromagnetic field, the method comprising the following steps by weight: Step 1: Preparation of Additive A: Add 78.3 parts of deionized water and 4.2 parts of hydrophilic fumed silica at 35℃, stir at 400 rpm for 30 minutes, add 8.5 parts of sodium polyoxysuccinate, stir at 1200 rpm for 20 minutes, then adjust the speed back to 400 rpm and slowly pump in 1.1 parts of sodium perfluorononenoxybenzenesulfonate aqueous solution (prepared as a 10% solution with 8.7 parts of deionized water) at a rate of 0.1 parts / minute. After pumping, increase the speed to 1200 rpm and stir for 20 minutes to obtain mixture A. 0.55 parts of graphene powder and 6.5 parts of glycerol were premixed at 800 rpm for 5 minutes and added to mixture A. The mixture was stirred for 20 minutes and then homogenized once under circulating water cooling at 30°C and pressures of 30 MPa (first stage) and 5 MPa (second stage). The mixture was then stirred and degassed at -0.08 MPa and 30 rpm for 30 minutes. The mixture was then filtered using a polypropylene bag filter with a pore size of 5 microns at 0.1 MPa to obtain additive A.

[0031] Step 2, Substrate Pretreatment: Take a 304 stainless steel substrate with dimensions of 50 mm × 100 mm × 1 mm, and polish the surface sequentially using 800 grit, 1200 grit, and 2000 grit silicon carbide wet sandpaper. Immerse the polished substrate in an alkaline degreasing solution at 65°C (containing 30 g / L sodium hydroxide, 25 g / L sodium carbonate, 15 g / L sodium phosphate, and 5 g / L sodium silicate) for 15 minutes. Then, ultrasonically clean it with 60°C deionized water for 5 minutes. In a 10% (v / v) dilute sulfuric acid solution, with the substrate as the cathode and a lead plate as the anode, apply a current density of 5 amperes / dm² for 30 seconds to activate it. Rinse it with flowing deionized water for 30 seconds, immerse it in anhydrous ethanol for dehydration, and dry it in an 80°C forced-air drying oven for 10 minutes. After drying, transfer it to the deposition station.

[0032] Step 3: Prepare the precursor electrolyte: Add 1000 parts deionized water, 52 parts nickel sulfate hexahydrate, 6.8 parts ferrous aminosulfonate, 1.1 parts ammonium metatungstate, 12.5 parts sodium citrate, 29 parts sodium sulfate, and 4.2 parts sodium bisulfate. Stir at 300 rpm for 10 minutes at 35°C. Add 0.22 parts sodium saccharin and 0.08 parts sodium dodecyl sulfate, and stir for 10 minutes. Add 4 parts of the auxiliary agent A prepared in Step 1 at 45°C, increase the stirring speed to 500 rpm, and stir for 20 minutes. Adjust the pH of the electrolyte to 4.0 to obtain the precursor electrolyte for use.

[0033] Step 4, Electromagnetic field controlled deposition: Install the pretreated substrate from Step 2 onto the cathode rod of the deposition tank, place two pure nickel plates as anodes on both sides, with an anode-cathode area ratio of 1:2, inject the electrolyte prepared in Step 3 into the deposition tank, turn on the magnetic stirring, set the speed to 150 rpm, and stabilize the water bath temperature at 45℃. Turn on the DC power supply, using constant current mode, and set the current density to 2 amperes per square decimeter. Simultaneously activate the electromagnetic field system: set the static bias magnetic field strength to 0.1 Tesla, the low-frequency alternating magnetic field to 5 Hz and 0.03 Tesla, and temporarily disable the high-frequency pulsed electric field. This initial deposition phase lasts for 10 minutes. Entering the main deposition stage, while keeping the current density constant, the static bias magnetic field strength is linearly increased to 0.2 Tesla within 5 minutes, the low-frequency alternating magnetic field frequency is synchronously increased to 10 Hz and the peak field strength is increased to 0.08 Tesla, and the high-frequency pulsed electric field (pulse frequency 800 Hz, pulse width 50 microseconds, peak field strength 3000 V / m) is activated. This stage lasts for 60 minutes. Entering the gradient deposition stage, in the final 10 minutes, the current density is linearly reduced from 2 A / dm² to 1 A / dm². Simultaneously, the static bias magnetic field strength is reduced from 0.2 Tesla to 0.08 Tesla, while the low-frequency alternating magnetic field frequency is increased from 10 Hz to 30 Hz. The high-frequency pulsed electric field parameters remain unchanged. After deposition, disconnect all power and electromagnetic fields. Remove the coated substrate, rinse the surface with running deionized water, immerse it in a 1% (mass fraction) ammonia solution for 10 seconds to neutralize, remove it and rinse again with deionized water until the pH of the effluent is 6.5, and finally dry it in an 80℃ forced-air drying oven for 5 minutes to complete the deposition.

[0034] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that no additive A is added; otherwise, they are the same as in Example 1.

[0035] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that when preparing additive A, 0.5 parts of graphene powder are not added, and the step of premixing with glycerol is cancelled accordingly. The rest is the same as Example 1.

[0036] Comparative Example 3 The difference from Example 1 is that when preparing additive A in Comparative Example 3, 10 parts of sodium polyoxysuccinate were not added. After adding fumed silica, the step of adding sodium perfluorononenoxybenzenesulfonate aqueous solution was carried out directly. The other contents are the same as in Example 1.

[0037] Comparative Example 4 The difference from Example 1 is that in Comparative Example 4, no 1 part of ammonium metatungstate was added when preparing the precursor electrolyte. That is, the electrolyte does not contain a tungsten source, but all other contents are the same as in Example 1.

[0038] Comparative Example 5 The difference between Comparative Example 5 and Example 1 is that 0.2 parts of sodium saccharin were not added when preparing the precursor electrolyte, that is, the electrolyte did not contain stress modifiers. All other contents are the same as Example 1.

[0039] Comparative Example 6 The difference from Example 1 is that in the preparation of additive A in Comparative Example 6, 1 part of sodium perfluorononenoxybenzenesulfonate was replaced with an equal weight of sodium dodecyl sulfate. All other contents are the same as in Example 1.

[0040] Comparative Example 7 The difference from Example 1 is that in step 4 of Comparative Example 7, during electromagnetic field-controlled deposition, only a static bias magnetic field is applied, and the low-frequency alternating magnetic field and high-frequency pulsed electric field are not activated. Specifically, during the initial and entire deposition stage, only the static bias magnetic field strength is activated and maintained at 0.25 Tesla, and all settings and dynamic changes of the alternating magnetic field and pulsed electric field are canceled. The total deposition time and stage division are the same as in Example 1, and other contents are consistent with Example 1.

[0041] Comparative Example 8 The difference from Example 1 is that Comparative Example 8 does not apply any electromagnetic field and uses conventional DC electrodeposition. Specifically, in step 4, no electromagnetic field system is activated (static magnetic field, alternating magnetic field, and pulsed electric field are all turned off), only the DC power supply is turned on, constant current mode is used, the current density is set to 2 amperes / square decimeter, and deposition is carried out at 50°C for 150 minutes. Other contents are the same as in Example 1.

[0042] Performance testing Microhardness, coating adhesion, wear resistance, corrosion resistance, and coating internal stress were tested on the examples and comparative examples. The specific methods are as follows: Microhardness was tested using a micro Vickers hardness tester (SHIMADZU, Japan, model HMV-G series). Test conditions: 0.98 N (100 gf) load, holding time 15 seconds. Ten points were tested for each sample, and the highest and lowest values ​​were discarded, and the average value was taken. Coating adhesion was evaluated using the scratch test method with a multi-functional material surface performance tester (CSM Instruments, Switzerland, model Revetest). A diamond indenter (tip radius 200 μm) was used, the loading force increased linearly from 0 N to 80 N, the scratch length was 5 mm, and the loading rate was 80 N / min. The critical load (Lc2) at which the coating completely peels off (the substrate is completely exposed), determined by both optical microscopy and acoustic emission signals, was used as the quantitative index of coating adhesion. Each sample was tested three times, and the average value was taken. Wear resistance was tested using a ball-and-disc tribo-wear testing machine (Bruker, UMT TriboLab, USA) under dry friction conditions. The grinding balls were 6 mm diameter alumina ceramic balls, with a normal load of 10 N, a rotation radius of 5 mm, a rotation speed of 200 rpm, and a total rotation speed of 10,000 rpm. After testing, the cross-sectional area of ​​the wear tracks was measured using a white light interferometer, and the volumetric wear rate (wear volume / (load × total sliding distance)) was calculated in units of 10-1. -6 mm 3 / (N·m). Corrosion resistance was tested using an electrochemical workstation (Gamry, Interface 1010E, USA) in a three-electrode system with potentiodynamic polarization curves. The working electrode was the coated sample (exposed area 1 cm²), the reference electrode was a saturated calomel electrode (SCE), and the auxiliary electrode was a platinum sheet. The electrolyte was a 3.5 wt.% NaCl solution, and the temperature was 25 °C. The scan range was ±0.25 V relative to the open circuit potential (OCP), and the scan rate was 1 mV / s. The self-corrosion current density (Icorr) was calculated using the Tafel extrapolation method. A lower Icorr value indicates better corrosion resistance of the coating. The internal stress of the coating was estimated using the substrate curvature method. The change in the radius of curvature of the thin substrate (50 mm × 10 mm × 0.1 mm) before and after deposition was measured using a surface profilometer (KLA-Tencor, P-7, USA), and the average macroscopic stress within the coating was calculated according to the Stoney formula. The results are shown in Table 1.

[0043] Table 1: Performance Test Results of Examples and Comparative Examples As shown in Table 1, Example 1 of the present invention successfully achieved the refinement of the coating microstructure, the uniform dispersion of the nano-reinforcing phase, and the effective control of internal stress through the organic combination of special additive A and dynamic synergistic regulation of multi-physics fields. Therefore, it exhibits the optimal combination of comprehensive performance: extremely high microhardness, excellent adhesion, excellent wear resistance and corrosion resistance, while the internal stress is a beneficial compressive stress (-180 MPa). Examples 2 and 3 slightly reduced the amount of additive, process intensity, or deposition time, resulting in a gradual and reasonable decrease in comprehensive performance, but still significantly outperformed all comparative examples in all aspects. This demonstrates that the technical solution of the present invention has a robust parameter window and a good dosage effect. In contrast, the coating structure of Comparative Example 1 was coarse, and the internal stress turned into high tensile stress, leading to a comprehensive deterioration of all performance aspects. This demonstrates the core role of additive A as a system stabilizer, structure refiner, and stress buffer. Comparative Examples 2 and 3 respectively resulted in uneven distribution of the reinforcing phase, decreased wear resistance, and a sharp drop in bonding strength, with internal stress turning into tensile stress. This demonstrates that each component within Additive A is indispensable for achieving uniform current distribution, guiding in-situ reactions, and regulating interfacial stress. Comparative Example 4, due to the inability to form a nano-tungsten carbide reinforcing phase, resulted in significantly insufficient coating hardness and wear resistance. Comparative Example 5 revealed the lack of a necessary synergistic relationship between the traditional stress modifier, Additive A, and the electromagnetic field in a high-performance system, leading to severe deterioration of bonding strength. Comparative Example 6 exhibited insufficient wetting and adsorption stability under complex electromagnetic fields, resulting in increased coating defects and a significant decrease in corrosion resistance. Comparative Examples 7 and 8 demonstrate that without multi-field coupling dynamic control, it is impossible to achieve precise control of ion behavior, in-situ uniform generation of nano-phases, and construction of a dense gradient structure. The resulting coatings exhibited common defects such as coarse structure and low performance. The special additive A of this invention and the dynamic synergistic control process of multi-physics fields (static magnetic field, alternating magnetic field, pulsed electric field) at a specific time sequence are an inseparable organic whole. The synergistic effect generated by the deep coupling of the two results in a simultaneous improvement in many key performance indicators of the coating.

[0044] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A material deposition method using electromagnetic field control, characterized in that, The method includes the following steps: S1. Preparation of auxiliary agent A; S2. Pre-treatment of the metal substrate; S3. Prepare the precursor electrolyte. The raw materials for preparing the precursor electrolyte include, by weight: 48-52 parts nickel sulfate hexahydrate, 6.3-6.8 parts ferrous aminosulfonate, 0.9-1.1 parts ammonium metatungstate, 11.5-12.5 parts sodium citrate, 29-31 parts sodium sulfate, 3.8-4.2 parts sodium bisulfate, 0.18-0.22 parts sodium saccharin, 0.08-0.12 parts sodium dodecyl sulfate, 1000 parts deionized water, and 4-5 parts auxiliary agent A. S4. Electromagnetic field controlled deposition: The pretreated metal substrate is placed into the deposition tank as the cathode, the precursor electrolyte is injected, electrodeposition is carried out in constant current mode, and a composite electromagnetic field is applied. The deposition process includes an initial deposition stage, a main deposition stage and a gradient deposition stage performed sequentially.

2. The method as described in claim 1, characterized in that, During the initial deposition stage, a static bias magnetic field and a low-frequency alternating magnetic field are applied, while the high-frequency pulsed electric field is not activated. During the main deposition stage, a high-frequency pulsed electric field is activated, and the strength of the static bias magnetic field and the frequency and field strength of the low-frequency alternating magnetic field are increased. During the gradient deposition stage, the deposition current density and the static bias magnetic field strength are reduced, while the frequency of the low-frequency alternating magnetic field is increased.

3. The method as described in claim 1, characterized in that, The raw materials for preparing additive A, by weight, include: 3.8-4.2 parts of hydrophilic fumed silica, 0.9-1.1 parts of sodium perfluorononenoxybenzenesulfonate, 8.5-9.5 parts of sodium polyepoxysuccinate, 0.45-0.55 parts of graphene powder, 87-89 parts of deionized water, and 5.5-6.5 parts of glycerol.

4. The method as described in claim 3, characterized in that, The preparation method of additive A includes: dispersing hydrophilic fumed silica in a portion of deionized water and stirring at 35°C and a first stirring speed for 30-60 minutes; adding sodium polyoxysuccinate and increasing the stirring speed to a second stirring speed for 20-30 minutes; adjusting the stirring speed back to the first stirring speed and adding an aqueous solution of sodium perfluorononenoxybenzenesulfonate, then increasing the stirring speed to a second stirring speed for 20 minutes to obtain mixture A; premixing graphene powder with glycerol for 5-15 minutes and adding it to mixture A, stirring for 20-40 minutes; circulating and homogenizing the stirred material; and vacuum stirring and degassing the homogenized material, followed by filtration to obtain additive A. The first speed is 400 rpm, and the second speed is 1200 rpm.

5. The method as described in claim 4, characterized in that, The conditions for circulating homogenization are as follows: under circulating water cooling, two-stage pressure is used, with the first stage pressure being 30-50 MPa and the second stage pressure being 5-10 MPa, and the cycle is repeated 1-5 times; the conditions for vacuum stirring and degassing are: vacuum degree -0.08 to -0.095 MPa, rotation speed 30 rpm, and degassing time 30-60 minutes.

6. The method as described in claim 1, characterized in that, Step S3 includes stirring deionized water, nickel sulfate hexahydrate, ferrous aminosulfonate, ammonium metatungstate, sodium citrate, sodium sulfate, and sodium bisulfate for 10-30 minutes at 35-40℃ and 300 rpm; adding sodium saccharin and sodium dodecyl sulfate and stirring for 10-30 minutes; adding auxiliary agent A at 45-50℃ and stirring at 500 rpm for 20-60 minutes, and adjusting the pH value to 4.

0.

7. The method as described in claim 1, characterized in that, During the initial deposition stage, the static bias magnetic field strength was 0.1-0.15 Tesla, and the low-frequency alternating magnetic field parameters were 5-10 Hz with a field strength of 0.03-0.05 Tesla. During the main deposition stage, the static bias magnetic field strength is linearly increased to 0.2-0.25 Tesla within 5 minutes, the frequency of the low-frequency alternating magnetic field is increased to 10-20 Hz and the field strength is increased to 0.08-0.1 Tesla, and a high-frequency pulsed electric field is activated. The pulse frequency of the high-frequency pulsed electric field is 800-1000 Hz, the pulse width is 50-100 microseconds, and the peak field strength is 3000-5000 V / m. The main deposition stage lasts for 60-120 minutes.

8. The method as described in claim 1, characterized in that, The gradient deposition stage takes place in the last 10-30 minutes after the main deposition stage, linearly reducing the deposition current density from 2 amperes / dm² to 1 ampere / dm², while simultaneously linearly reducing the static bias magnetic field strength from 0.2-0.25 Tesla to 0.08-0.1 Tesla, and linearly increasing the frequency of the low-frequency alternating magnetic field from 10-20 Hz to 30-50 Hz.

9. The method as described in claim 1, characterized in that, Step S2, the pretreatment of the metal substrate, includes: sequential polishing, alkaline degreasing, ultrasonic cleaning, electrochemical activation, water washing, dehydration, and drying; the alkaline degreasing solution contains 30 g / L sodium hydroxide, 25 g / L sodium carbonate, 15 g / L sodium phosphate, and 5 g / L sodium silicate; the electrochemical activation is carried out in a 10% (v / v) dilute sulfuric acid solution, with the substrate as the cathode, the lead plate as the anode, the current density as 5 amperes / dm², and the activation time as 30 seconds.

10. The method as described in claim 1, characterized in that, In step S4, a pure nickel plate is used as the anode, and the ratio of anode to cathode area is 1:

2. During the deposition process, the precursor electrolyte is magnetically stirred at a stirring rate of 150 rpm, and the water bath temperature is kept stable at 45-50℃.

Images