32 results about "Chromium free" patented technology

The invention discloses a chromium-free high-temperature-resistant treating fluid, a hot-dip aluminum-zinc environment-friendly coating plate and a preparation method of the hot-dip aluminum-zinc environment-friendly coating plate, and belongs to the technical field of hot-dip aluminum-zinc plates. The treating fluid comprises a corrosion inhibitor, silane, a phosphate radical-containing substance, an inorganic acid and a surfactant, and is prepared step by step according to a specific sequence. The chromium-free coating with the thickness of 0.6-1.2 m can be formed by coating the surface of a hot-dip aluminum-zinc plate with the chromium-free coating in a roller coating manner and curing at the temperature of 80-150 DEG C. The coating does not contain organic matters, does not yellow within 30 minutes at the high temperature of 390 DEG C, has excellent corrosion resistance, fingerprint resistance, alkali resistance and coatability, is suitable for inner plates of high-temperature household appliances such as microwave ovens and ovens, and has the characteristics of environment friendliness and high performance.

The invention provides a chromate-free passivation method for a zinc steel guardrail. The chromate-free passivation method comprises the steps that the average thickness of a hot galvanizing layer of the zinc steel guardrail is obtained; the passivation temperature is calculated according to a first control formula; the passivation time is calculated according to a second control formula; the zinc steel guardrail is immersed in a chromate-free passivation solution with the temperature of 50 DEG C, and the constant temperature is kept for time; and the zinc steel guardrail subjected to chromium-free passivation is taken out and dried, and a passivation film is formed on the hot galvanizing layer of the zinc steel guardrail in a curing mode. A chromium-free passivation system is adopted to meet the requirements of environmental protection laws and regulations, a correlation model of the average thickness of a hot galvanizing layer, the passivation temperature and the passivation time is established, passivation process parameter adaptation is achieved, the uniformity of the density and the adhesive force of a passivation film is remarkably improved, the corrosion resistance stability of guardrail products of different batches and different parts is guaranteed, and the service life of the guardrail products is prolonged. The service life of the zinc steel guardrail is prolonged, and meanwhile the core characteristics of high strength, high rigidity and the like are maintained.

The invention relates to a chromium-free environment-friendly insulating coating paint and a thin electrical steel strip. The chromium-free environment-friendly insulating coating comprises the following components in percentage by mass: 15%-23% of phosphate; 8%-13% of epoxy resin emulsion; 0.3%-1.2% of boric acid; 0.4%-4.7% of a metal inorganic salt additive; 0.3%-1.1% of a metal hydroxide; 0.1%-0.44% of a coupling agent; 7%-26% of hollow ceramic microsphere particles; and 30.56% to 68.9% of deionized water. The metal inorganic salt additive is at least one of barium oxalate, strontium sulfate and aluminum silicate. The phenomena that solid components in the coating sink to the bottom and water is separated from the surface can be avoided, the compactness of the coating is improved, the wear resistance and corrosion resistance of the coating are improved, the resistivity of the insulating coating can be remarkably improved through the nanoscale hollow ceramic microsphere particles, the loss of electrical steel is reduced, the adhesiveness of the coating is enhanced, and cracks of the coating are reduced.

The invention relates to a chromate-free passivator for a copper bar for a new energy automobile battery and a preparation method of the chromate-free passivator, and belongs to the technical field of metal surface treatment.The chromate-free passivator comprises, by weight, 6-16 parts of organic azole compounds; 10 to 30 parts by weight of molybdate; 2-10 parts by weight of a silane coupling agent; 4 to 12 parts by weight of a water-soluble polymer; 1-6 parts by weight of an accelerant; 0.2 to 2 parts by weight of a surfactant; and the balance of deionized water. According to the chromium-free passivating agent for the copper bar for the new energy automobile battery and the preparation method of the chromium-free passivating agent, the prepared chromium-free passivating agent for the copper bar for the new energy automobile battery eliminates the harm of hexavalent chromium to the environment and operators from the source, completely meets the strict requirements of global green manufacturing and environmental protection laws and regulations, and has a wide application prospect. And support is provided for the concept of full-life-cycle environmental protection of new energy automobiles, the copper bar surface treatment industry is promoted to develop towards the environment-friendly and sustainable direction, and the advantage of remarkable environmental protection performance is achieved.

This invention discloses a chromium-free passivation and fingerprint-resistant composite treatment method for high-aluminum-zinc-aluminum-magnesium steel plates, belonging to the field of metal sheet surface protection technology. The specific steps of the method are as follows: A fine-grained high-aluminum-zinc-aluminum-magnesium steel plate is selected as the substrate, and firstly, it undergoes multi-stage cleaning and hot air drying. Next, the dried substrate is immersed in a composite chromium-free passivation solution to form a passivation precursor film. Then, a porous inorganic passivation layer is prepared through low-temperature hot air curing. Subsequently, a modified fingerprint-resistant resin is roller-coated onto its surface to form an organic precursor film. Finally, a constant-temperature curing treatment is performed to produce a chromium-free passivation and fingerprint-resistant composite film. This invention uses multi-stage cleaning and chromium-free passivation processes on the high-aluminum-zinc-aluminum-magnesium steel plate to form a porous inorganic passivation layer, enhancing corrosion resistance. Then, a composite protective film layer is constructed by reverse roller coating of modified fingerprint-resistant resin, achieving functional integration. This process improves the environmental protection and protective properties of the plate, meets the needs of multiple fields, and expands the application scenarios and market scope.

The present application belongs to the technical field of electrolytic copper foil, and provides a chromium-free anti-oxidation method for electrolytic copper foil, which solves the problem of copper foil oxidation under chromium-free condition. The electrolytic copper foil is sequentially subjected to pickling, roughening I, roughening II, electroplating, passivation, silane coupling and drying to complete the treatment of the electrolytic copper foil. In the process of treating the copper foil, a Ni-Cu-Sn alloy layer is deposited on the surface of the copper foil through a specific composition of electroplating solution, so as to achieve the purpose of preliminary protection. Then, passivation is carried out in a passivation solution, and the passivation solution can effectively form an organic adsorption film to inhibit the oxidation of the electrolytic copper foil. On the basis of abandoning the addition of chromate, the present application can still well improve the anti-oxidation property of the electrolytic copper foil, and there is no oxidation discoloration under high-temperature and high-humidity conditions, and the electrolytic copper foil is resistant to chemical reagents, and the tensile strength under high temperature reaches 406 MPa, and has excellent mechanical properties.

The invention belongs to the technical field of textile machinery, and discloses a partitioned reinforced composite structure triangle for a composite needle circular weft knitting machine and a forming method thereof.The partitioned reinforced composite structure triangle for the composite needle circular weft knitting machine comprises a working face area, a toughness transition area and an installation base body area; the working face area, the toughness transition area and the installation base body area are made of high-carbon and high-chromium free-cutting steel, medium-carbon and medium-chromium free-cutting steel and low-carbon and low-chromium free-cutting steel respectively. The preparation method comprises the following steps: firstly, designing a precise pressing die according to a triangular three-dimensional model, partitioning a die cavity into a working surface region, a toughness transition region and a mounting base body region according to function regions, and accurately filling each powder cavity with free-cutting steel powder with corresponding components; and performing cold isostatic pressing, high-temperature vacuum sintering, heat treatment and finish machining to obtain the partitioned reinforced composite structure triangle for the composite needle circular weft knitting machine. The technical problem that high wear resistance, high impact resistance and excellent machining manufacturability of a traditional triangle are difficult to consider at the same time is systematically solved, the service life of the triangle is remarkably prolonged, and the reliability of the triangle is remarkably improved.

The application discloses a chromium-free inorganic surface treatment agent for galvanized steel plate, which contains 11.5-15% of total solid content in mass percentage in an aqueous solution, and components of the total solid content are as follows: a compounded silane coupling agent A, which accounts for 45-65% of the total solid content in mass percentage; a surface modified water-based silica sol B, which accounts for 25-45% of the total solid content in mass percentage; a water-soluble phosphorus-containing compound C, which accounts for 0.5-1% of the total solid content in mass percentage of phosphorus element; a water-soluble fluorine-containing compound D, which accounts for 1-6% of the total solid content in mass percentage of fluorine element; and a lubricating aid E, which accounts for 1-10% of the total solid content in mass percentage; wherein the compounded silane coupling agent A is compounded by four types of silane coupling agent monomers, i.e., a silane A1 with an epoxy group, a silane A2 with a mono-amino group, a silane A3 with an alkyl group and a silane A4 with a vinyl group.

This invention belongs to the field of passivating agent technology, specifically relating to a corrosion-resistant, high-temperature-resistant, chromium-free passivating agent for magnesium alloy workpieces and its preparation method. The chromium-free passivating agent comprises the following components by weight: 4-5 parts film-forming agent; 8-10 parts functional acrylic resin; 0.8-1 parts vanadate; 3-5 parts coupling agent; 1-2 parts corrosion inhibitor; and 70-80 parts water. The chromium-free passivating agent provided by this invention uses zirconium fluoride and titanium fluoride as film-forming agents, and is modified by adding functional acrylic resin, which improves the density and corrosion resistance of the passivation film. This results in a chromium-free passivating agent with good corrosion resistance, adhesion, high-temperature resistance, and antibacterial properties. When used in magnesium alloy workpieces, it exhibits good corrosion resistance and helps extend the service life of the magnesium alloy workpieces.

The present application relates to passivation liquid technical field, especially IPC C23C22, more particularly to, in the coastal low latitude area uses the chromium-free passivation liquid and its preparation method and application, the present application provides a kind of chromium-free passivation liquid in the coastal low latitude area uses, its preparation raw material includes molybdate, inorganic acid, alcohol amine, nanosol, water-based polyurethane, crosslinking agent, fatty amine soap premix, water-based ultraviolet absorber, water-based wax emulsion, penetration desiccant, water.The chromium-free passivation liquid in the present application can form a layer of superhydrophobic, low water absorption, high density, salt fog corrosion resistance, UV aging resistance, moisture resistance chromium-free passivation film, suitable for being in the galvanized aluminum magnesium steel coiled material in the coastal low latitude area.

The utility model relates to the technical field of hot-dip galvanizing, and discloses a chromate-free production device with a dust removal function, which comprises a fixed frame and a dust collection barrel, a telescopic mechanism is fixedly arranged at the midpoint of one side of the upper end surface of the fixed frame, and the telescopic mechanism comprises a fixed block; a plurality of sections of telescopic plates are clamped to the front end and the rear end of one side of the fixing block, a plurality of sections of electric telescopic rods are clamped to the middle point of one side of the fixing block, and a connecting block is clamped to one side of each of the two sections of telescopic plates. According to the dust collection device, after the telescopic mechanism and the first telescopic hose are arranged on one side of the dust collector, the second telescopic hose and the dust collection head which are arranged on one side of the first telescopic hose can be better moved, so that dust far away from the dust collector can be absorbed; the rotating piece is arranged to enable the dust collection head to collect dust at different angles, and the dust collection barrel is arranged to carry out dust falling treatment on discharged smoke dust.

The invention discloses a high-toughness low-splashing welding rod coating and a preparation method and application thereof, and belongs to the technical field of welding materials. According to the technical scheme, the raw materials comprise TiO2, CaCO3, potassium feldspar, graphite powder, iron powder, lignocellulose, alloy powder and sodium silicate. The alloy powder is composed of FeMn alloy powder, FeSi alloy powder and FeNi alloy powder according to the mass ratio of (1.5-2.5): (1.5-2.0): (0.8-1.0). According to the high-toughness and low-splash welding rod coating, through synergistic fine grain strengthening of FeMn / FeSi / FeNi and micro-explosion arc stabilizing of lignocellulose, a silicate binder containing hexavalent chromium is replaced with a sodium silicate binder, the splash amount can be smaller than or equal to 0.40 g / min <-1 >, the impact toughness at the temperature of-20 DEG C is larger than or equal to 90 J, and the high-toughness and low-splash welding rod coating meets the European Union RoHS instruction, the OSHA standard and the chromium-free requirement of the national standard GB / T26572.

The utility model relates to the technical field of metal manufacturing, provides a chromium-free passivation coating structure on the surface of an aluminum alloy profile, and solves the problems of low adhesiveness, relatively poor weather resistance and poor appearance bright effect of the coating structure on the surface of the existing aluminum profile. Which comprises a coating structure body and is characterized in that the coating structure body comprises a base material layer on the innermost layer, a first pretreatment layer on the secondary inner layer, a second pretreatment layer on the middle layer, a chromium-free passivation layer on the secondary outer layer and a sealing layer on the outermost layer; and the thickness of the sealing layer is 10-70 microns.

The invention belongs to the technical field of high-performance refractory materials, relates to a surface layer gradient densification method of a whisker toughened chromium-free refractory product and the product, and provides the surface layer gradient densification method of the whisker toughened chromium-free refractory product. A chromium-free refractory product containing an Al / Si-N-O-C non-oxide whisker reinforced phase is placed in steeping liquor to be steeped to form a gradient compact layer; the impregnated chromium-free refractory product is dried, so that active ingredients are enriched towards a surface layer area; and the dried chromium-free refractory product is subjected to heat treatment, so that active components enriched on the surface layer are reacted and sintered, and a gradient compact barrier layer chemically combined with the matrix is formed. According to the invention, the special structure of the internal gradient compact layer is constructed to realize whisker oxidation protection, so that not only is the problem of whisker oxidation in an oven solved, but also the gradient compact layer endows the product with higher surface hardness, wear resistance and slag permeability resistance, the effect of one stone with multiple birds is realized, and the service life of the product is prolonged. The safety and the service life of the product are systematically improved.

The invention relates to a coating agent for coating acid-sensitive metal surfaces, which is an aqueous solution of an acidic phosphate binder, the coating agent comprising a peroxo compound and being free of chromium (VI) salts. The invention further relates to a method of coating a metal surface with such a coating agent, and to the use of such a coating agent for increasing the corrosion resistance of metal components in various industrial fields.

The application discloses a chromium-free water-based protective agent for full-tin plating products, which has excellent performance, and contains a urethane prepolymer A, wherein the urethane prepolymer A is obtained by reacting a trimer of diisocyanate with 2-hydroxyphosphonoacetic acid, and the molar ratio of the trimer of diisocyanate to 2-hydroxyphosphonoacetic acid is 1:3. When the chromium-free water-based protective agent is used to treat a full-tin plating layer, the following performance requirements can be achieved: excellent corrosion resistance, meeting the performance requirement of 72 hours of salt spray; excellent conduction performance, with extremely low surface contact impedance of the metal tin itself; excellent stability, with the protective film being able to stably exist for a long time and resisting various storage environments; and excellent welding performance, with the tin plating area of the immersed pure tin being more than 98% after high-temperature and high-humidity aging test.

The invention relates to metal surface treatment, in particular to a chromium-free composite protective coating for the surface of a zinc impregnation layer and a preparation method of the chromium-free composite protective coating. Deionized water is used for adjusting the pH value, a silane coupling agent is added under stirring for hydrolysis, modified silica sol, rare earth salt and a water-soluble photoinitiator are added and evenly mixed, and a chromium-free passivation solution is obtained; the method comprises the following steps: dip-coating a pre-treated sherardizing workpiece in a chromium-free passivation solution to form a wet film, and converting the wet film from a free liquid state into a gel-state passivation film with reaction activity through a pre-drying procedure; applying a water-based sealing agent on the gel-state passivation film; the workpiece covered with the passivation film and the sealing agent is subjected to ultraviolet irradiation for several times, the sealing agent is cured at the same time, a cross-linking reaction is initiated at an interface, and an interpenetrating polymer network structure with gradient transition is formed. And meanwhile, the corrosion resistance, the adhesive force, the chemical stability and the like reach or even exceed those of a chromium passivation technology.

The present invention discloses a chromium-free inorganic surface treatment agent, wherein the surface treatment agent comprises total solids in percentage by mass of 11.5-15%, with a balance being water; the total solids consist of the following components in percentage by mass: compounded silane coupling agent A: 45-65%; surface-modified aqueous silica sol B: 25%-45%; water-soluble phosphorus-containing compound C: 0.5%-1%, based on a mass of phosphorus element; water-soluble fluorine-containing compound D: 1%-6%, based on a mass of fluorine element; and lubricating additive E: 1%-10%; wherein the compounded silane coupling agent A is obtained by compounding monomers of the following four types of silane coupling agents: epoxy-containing silane A1, monoamino-containing silane A2, alkyl-containing silane A3, and vinyl-containing silane A4.

The present application belongs to the technical field of textile machinery, and discloses a partition-strengthened composite structure cam for a compound needle circular weft knitting machine and a forming method thereof. The partition-strengthened composite structure cam for the compound needle circular weft knitting machine comprises a working surface area, a toughness transition area and a mounting base area. The working surface area, the toughness transition area and the mounting base area respectively adopt high-carbon high-chromium free-cutting steel, medium-carbon medium-chromium free-cutting steel and low-carbon low-chromium free-cutting steel. The preparation method comprises the following steps: first, a precision die is designed according to a three-dimensional model of the cam, a die cavity is isolated into the working surface area, the toughness transition area and the mounting base area according to functions, and free-cutting steel powder with corresponding components is accurately filled into each die cavity; then, cold isostatic pressing forming, high-temperature vacuum sintering, heat treatment and finishing are performed to obtain the partition-strengthened composite structure cam for the compound needle circular weft knitting machine. The present application systematically solves the technical problem that the traditional cam is difficult to simultaneously consider high wear resistance, high impact resistance and excellent processing workability, and significantly improves the service life and reliability of the cam.

The utility model belongs to chromium passivation agent spraying equipment technical field especially for a kind of chromium passivation agent spraying device for the surface of aluminium material, for efficiency problem, present and propose the following scheme, it includes pillar;The upper surface of the pillar is fixed with shell;The outer surface of the shell is rotatably installed with sealing plate;One side outer surface of the shell is equipped with No. The inner surface of the first sliding slot is slidably installed with mounting plate;The upper surface of the mounting plate is rotatably installed with carrier plate;The upper surface of the shell is fixed with connecting plate;One side outer surface of the connecting plate is rotatably installed with No. One side outer surface of the connecting plate is fixed with No. The setting of motor and No. 3 motor, the aluminium material can be sprayed faster and more evenly, and the efficiency is improved;The setting of No. 2 motor, aluminium material can be taken, and the efficiency is improved.

This invention relates to the field of steel plate surface treatment technology, specifically disclosing a chromium-free surface treatment liquid for color steel plates and its preparation method. The treatment liquid comprises zirconium-titanium composite sol, cerium nitrate, lanthanum nitrate, nano-silica, organosilane coupling agent, potassium fluorozirconate, etc. The preparation method is as follows: first, the silane coupling agent is hydrolyzed and then surface-grafted with nano-silica under cerium ion catalysis; then, the zirconium-titanium sol is coordinated and stabilized with rare earth ions and potassium fluorozirconate; finally, the two are mixed and undergo a co-condensation reaction to form a hybrid network. This invention, through stepwise chemical reactions, utilizes the dual functions of cerium ions (catalysis and bridging) and the controllable complexation of fluoride ions to tightly bind the components through covalent and coordinate bonds, solving the problems of poor component compatibility and wasted reactivity in existing chromium-free technologies. The film formed by this treatment liquid is dense, has strong adhesion, excellent corrosion resistance, and is completely free of hexavalent chromium, making it safe and environmentally friendly.

The invention discloses a chromium-free passivation treatment agent for a color-coated sheet. The chromium-free passivation treatment agent comprises the following raw materials in percentage by mass: 1-3% of a silane coupling agent, 3-5% of a citrate zirconium-titanium compound, 5-10% of thermosetting acrylic resin, 1-5% of a curing agent and the balance of pure water. The invention further discloses a preparation method, the problems that an existing chromium-free passivator is poor in corrosion resistance and adhesive force are solved, the chromium-free passivator is high in adhesive force and can be tightly attached to paint and the like, the protection performance of a color-coated sheet is improved, and the service life of the color-coated sheet is prolonged. The chromium-free passivator is green and environment-friendly and does not contain toxic heavy metal components. The chromium-free passivating agent also has the characteristic of high temperature resistance, so that the chromium-free passivating agent can adapt to multiple environments in the process steps.

The invention relates to the technical field of passivating agents, and discloses a chromium-free passivating agent for corrosion prevention of an AZ31B magnesium alloy and a production process of the chromium-free passivating agent. Comprising the following raw materials: polyurethane acrylic resin, glycidyl methacrylate, anti-corrosion vinyl chloride-vinyl acetate resin, a self-repairing compound, 1-hydroxycyclohexyl phenyl ketone, propylene glycol methyl ether acetate, a flatting agent and a defoaming agent. The anti-corrosion vinyl chloride-vinyl acetate resin and the self-repairing compound participate in the preparation process of the passivator, so that the prepared passivator has excellent corrosion resistance, mechanical strength, adhesive force and self-repairing capacity, is not prone to falling off and scratching when acting on the magnesium alloy, can be used for repairing small cracks when the small cracks are generated, and has the advantages that the service life of the passivator is prolonged, and the service life of the passivator is prolonged. And the integrity of the anti-corrosion barrier effect is effectively kept, so that the magnesium alloy protective coating can play a more excellent and long-acting magnesium alloy protective effect.

A coated component includes a metallic body defining an inner volume configured to retain a fluid therein. The metallic body includes a plurality of segments, at least one weld joint attaching the plurality of segments, an outer surface, and an inner surface facing and defining the inner volume. The component further includes a chrome-free protective coating disposed on each of the outer surface and the inner surface. The coating includes an epoxy layer, and an oxide layer disposed between the epoxy layer and the respective outer surface and inner surface.

The present application relates to a kind of method for preparing chrome-free flocking powder using chromium-containing uniform shaving leather scrap.First, the chromium-containing uniform shaving leather scrap is crushed and water is added to make a uniform slurry, then the slurry is chrome-free tanned and chromium is removed, and through the processes of re-filling, dyeing, fatting, centrifugal dewatering, drying, roughening and screening, finally the excellent performance chrome-free flocking powder product is obtained.The present application converts the chromium-containing uniform shaving leather scrap into high-value and widely used powder-like flocking powder with simple process, low cost and high production efficiency, which has a smooth and smooth hand feeling and can give the electrostatic flocking product a good leather feeling, and has a good market prospect.

The utility model relates to galvanized strip steel passivation technical field discloses a kind of automatic spraying equipment of chromium-free passivation solution of galvanized strip steel, including bottom plate, the bottom plate top end both sides are fixedly connected with support frame, the support frame top end inner wall is rotatably connected with guide roller, the bottom plate top end left side is fixedly connected with spraying box, the spraying box left and right ends are provided with first slot, the spraying box front end inner wall both sides are fixedly connected with spray plate, the spray plate front end is fixedly connected with shunt pipe, the bottom plate top end is relative to the liquid supply component of spraying box bottom side and is provided with.This utility model, through connecting pipe import shunt pipe, then chromium-free passivation solution is sprayed on the surface of galvanized strip steel by spray head, and it is passivated to be handled, when galvanized strip steel moves in spraying box, extra chromium-free passivation solution drops in collecting groove, after filtering screen filtration, by liquid outlet pipe reflows into liquid storage tank, realizes the recycling of chromium-free passivation solution, reduces waste.

The application discloses a chromium-free passivator for aluminum and aluminum alloy and a preparation method thereof. The chromium-free passivator comprises the following components: cerium nitrate 2.0-5.0 g / L, lanthanum nitrate 1.0-3.0 g / L, yttrium nitrate 0.5-2.0 g / L, fluorosilane modified nano-SiO2 1.0-3.0 g / L, chelate type titanate coupling agent 0.5-1.5 g / L, citric acid 3.0-8.5 g / L, 30% hydrogen peroxide 1.0-3.0 mL / L, potassium fluorozirconate 0.5-2.0 g / L, amino silane coupling agent 1.0-5.0 mL / L, pH regulator 0.01-3.0 mL / L, and the rest is deionized water. The chromium-free passivator has high adhesion and excellent hydrophobicity, is not corroded under neutral salt spray for 500 hours, can resist copper accelerated acetate salt spray for more than 120 hours, and meets the industrial requirements of aluminum alloy product surface treatment.

The invention relates to the technical field of passivating agents, in particular to a chromium-free passivating agent as well as a preparation method and an application method of the chromium-free passivating agent. Comprising the following components: 2-3% of ammonium hexafluorotitanate, 6-8% of silica sol, 2-3% of sodium molybdate, 0.2-0.5% of polyether modified heptamethyltrisiloxane, 10-15% of a silane coupling agent, 1-2% of a titanate coupling agent, 18-20% of modified acrylic resin, 0.5-1% of an adhesion promoter and 55-60% of deionized water. By regulating and controlling the content of each raw material, compared with a passivation layer produced by a conventional passivation agent, the prepared passivation agent has better color and luster, and the passivation layer is high in hardness, good in wear resistance and good in corrosion resistance; when the prepared chromium-free passivator is applied to a passivation process, the problems that the environment is polluted and the production cost of enterprises is increased due to the fact that trivalent chromium is adopted as the passivator in an existing passivation process can be solved.

The invention discloses a chromium-free surface treatment zinc-aluminum-magnesium coated steel plate and a manufacturing method thereof. The chromium-free surface treatment zinc-aluminum-magnesium coated steel plate is obtained by coating the surface of a zinc-aluminum-magnesium coated steel plate with a water-based chromium-free surface treatment agent to form a composite film; the water-based chromium-free surface treating agent comprises, by mass, 45%-65% of a coupling agent, 10%-20% of water-based resin, 5%-15% of water-based nanoparticles, 5%-10% of a water-soluble phosphorus-containing compound in terms of phosphorus and 1%-5% of a lubricant. The chromium-free surface treatment zinc-aluminum-magnesium coated steel plate not only can ensure the anti-rust effect of the zinc-aluminum-magnesium coated steel plate, but also can show excellent adhesion and aging resistance in the processing link, and has good popularization potential and application value.