816 results about "Salt spray test" patented technology

The invention provides a preparation method of a magnesium alloy surface micro-arc oxidation/spray coating compound film, which relates to a preparation method of a magnesium alloy surface compound film. The invention solves the problems that film layers obtained by chemical composition coating, anodic oxidation and vapor deposition in the existing magnesium alloy surface treatment method are thin and have poor corrosion resistance performance, the ion injection has high cost and is difficult to realize large-area processing, the combining force between coating layers and the magnesium alloy is poor, and organic coating layers has the defect of easy aging. The preparation method has the following steps: firstly, using micro-arc oxidation for preparing ceramic films on the surface of the magnesium alloy; then, adopting air spray coating for spraying and coating inorganic paint onto the ceramic films; and then, carrying out heat treatment to obtain the micro-arc oxidation/spray coating compound film. The method is simple, and the cost is low. The air spray coating uses porous structures of the micro-arc oxidation ceramic films, so the combination of the inorganic coating layers and the ceramic films is firm, the thickness of the compound films is between 20 and 40 mum, the self corrosion electric potential is positively moved to -1.02 V, the corrosion current density is lowered by 5 orders through being compared with that of the magnesium alloy, the magnesium alloy surface micro-arc oxidation/spray coating compound film has no damage after 72 to 144h of salt spray tests, and the corrosion resistance performance is good.

The invention relates to a method for producing color-coated steel sheet for a structure. The method comprises the following steps of: smelting, namely desulfurizing by molten iron, smelting by a converter, casting continuously to form a blank and performing hot rolling; performing acid washing; performing cold milling; annealing continuously; performing hot dipping on aluminum and zinc; and polishing, straightening, performing color coating and packaging for later use. In the method, the yield strength RP 0.2 (or ReH) is between 550 and 600 MPa; the tensile strength Rm is between 560 and 610MPa; and the percentage elongation after break A80 mm is more than or equal to 6 percent. A neutral salt mist test is performed for 1,200 hours, a coating does not have bubbling and corrosion phenomena. At present, the annealed color-coated plate of which the metallographic structure is ferrite and pearlite or the ferrite and free cementite or the ferrite and the pearlite and less free cementite cannot achieve the effect, and the production cost can be reduced by 10 to 15 percent. By the method, special occasions which have high-yield strength and are used for cooling chambers of automobiles,arch coverings and the like can be met, and a process is simple and easy to implement.

The invention discloses a method for electroplating alkaline Zn-Ni alloy, comprising the steps of: preparing alkali wash and acid wash, preparing electroplating Zn-Ni alloy plating solution, mechanical grinding, degreasing with organic solvent or water-based detergent, alkali washing, acid washing and electroplating. The invention provides a stable electroplating solution formula and complete electroplating process. The coating electroplated by the method is proved to have good flat surface, uniform coating distribution and alloy distribution, the coating is single gamma-phase, the nickel has a content of 10% to 15%; the coating has superior corrosion resistance, red rust appears on the non-passivated Zn-Ni coating after 1500 hours in a neutral salt spray test; compared with general alkali electroplating solution, the coating has high current efficiency, reaching up to 80% to 90%.

The invention relates to a coating simulation accelerated test method, comprising a damp heat test, a solar radiation test, a salt mist test, characterized in that the damp heat test, the solar radiation test and the salt mist test are combined in precedence order and circulate; circulation time of the damp heat test, the solar radiation test and the salt mist test is more ten. The coating simulation accelerated test method of marine environment adaptation check is reasonable, effective and rapid and obtains the outdoor long-time exposure test result using the indoor short-time testing; solves the practical problems of development and use, in favor of application and popularization of coating material.

The invention discloses a passivating treating agent for environment-friendly galvanized steel sheets, which is composed of 2-20% of silane, 1-5% of anti-rusting metal salt, 8-20% of resin, 0.1-5% of coating additive, 0.5-5% of pH regulating agent and 50-70% of water. The passivating treating agent features in simple and convenient preparation process and mainly depends on mixing production; drying temperature thereof is as low as 50-60 DEG C, in 96 hours, salt mist resistance property is no more than 3% and performance thereof is good.

The invention relates to the field of metal surface treatment, and especially relates to a neodymium-iron-boron magnetic material zinc-series phosphatization liquid. The phosphatization liquid is mainly used in neodymium-iron-boron surface anti-corrosion protection and cathodic electrophoresis priming and phosphatization. The liquid is characterized in that a mass ratio of Zn<2+>:PO4<3->:NO<3->:F<->:an accelerator is (3.5-10.5):(14-41.3):(7.3-21.9):(0.95-2.8):1, Ni<2+> is 0.01-0.2g/L, an organic complexing agent is 0.04-0.18g/L, the promoter is 0.2-1.5g/L, and balance is water. Free acidity of a phosphatization working liquid is 3-8 points, a total acidity is 22-32 points, a phosphatization temperature is 48-55 DEG C, and a phosphatization time is 6-15min. When the phosphatization liquid is used for treating neodymium-iron-boron, a light grey to grey phosphate coating is produced, and 3% neutral salt water soaking time is above 3h. An electrophoresis coating cut test is 0 grade, and a neutral salt spray test is 500h.

The invention relates to a composite phosphating solution of P-Ca-V on the surface of a magnesium alloy and a method for chemical conversion treatment. The solution is characterized in that each liter of the composite phosphating solution comprises the following compositions: 4 to 20 milliliters of 85 percent phosphoric acid of, 5 to 30 grams of sodium dihydrogen phosphate, 10 to 40 grams of calcium nitrate, 0.5 to 10 grams of benzene sulfonic acid sodium salt, 0.5 to 5 grams of ammonium metavanadate, and the balance being water. The method comprises the following steps: pre-degreasing, degreasing, secondary water washing, acid washing, secondary water washing, alkaline etching, secondary water washing, chemical transformation, secondary water washing, pure water washing, and drying. Taking an AZ91D magnesium alloy as an example, 48 hours after a corrosion resistance salt spray test after the treatment by the method of the invention, the corrosion area of the AZ91D magnesium alloy is less than 1 percent; the paint film adhesive force is at 0 level by a grid method and is obviously superior to the performance of a chromate conversion coating; and the formed chemical conversion coating does not contain crystal water. The composite phosphating solution has the synergistic reaction of Ca and V, as well as the functions of a corrosion inhibitor and a wetting agent of the benzene sulfonic acid sodium salt.

The invention discloses a water-based ceramic anticorrosive coating containing aluminum phosphate as well as preparation and curing methods thereof. The water-based ceramic anticorrosive coating containing aluminum phosphate is prepared by adopting aluminium dihydrogen phosphate as a bonding agent, magnesium oxide and zinc oxide as a curing agent, aluminum powder as filler, magnesium chromate as a passivating agent and tetraethyl orthosilicate as an auxiliary agent. The coating is used for preparing a metal ceramic coating layer on a metallic matrix, and the coating layer can tolerate 1000h of neutral salt fog test and keep stable. The coating layer has good high-temperature oxidation resistance in a high-temperature (600 DEG C) oxidation environment. The coating layer can well protect metals in a normal-temperature salt-containing environment and a high-temperature oxidation environment.

The present invention relates to a technique of treating coat the film made of aluminum alloy fluorine-polymer. Material or part of aluminum alloy should be hard anodizing first and introduce fluorine-polymer in the pore or on the surface. We can also expend the pore first and introduce fluorine-polymer on the surface and in the pore later. Fuse fluorine-polymer and anode oxidation coat together by vacuum heat treatment for high temperature. It's suitable for part of optic-electronic equipment. Firstly, it has good extinction, doesn't fade and doesn't break off: secondly, it is rigid and wearable; thirdly, it contains fluorine-polymer, has low friction coefficient, has the capability of self-lubricating, so its wearable and anti-corrosive performance can be improved a lot; fourthly, it has capability of hydrophobicity and can bear litmusless salt spray, so it can sustain most of the corrosion in bad condition and corrodent matter. Fifthly, the surface is self-lubricating, and has the capability of self-lubricating and dustproof.

The invention relates to a magnesium alloy phosphorization solution, which is an aqueous solution containing phosphoric acid, calcium dihydrogen phosphate, sodium silicate, sodium molybdate and ammonium metavanadate. The invention also provides a magnesium alloy surface treatment method, which comprises a step of phosphorizing the surface of magnesium alloy by using the magnesium alloy phosphorization solution. The method uses a calcium phosphorization solution to phosphorize the surface of the magnesium alloy, does not require substances containing hexavalent chrome, fluorions and the like which are harmful to the environment and human bodies in the whole phosphorizing process, and is the environment-friendly method. The magnesium alloy surface treated by the method has high corrosion resistance, good bonding force and low surface resistance, wherein the corrosion area after 60 hours of a neutral salt spray test can reach less than 5 percent, the bonding force can reach 5B level, andthe surface resistance can be lower than 0.0002 ohm.

The invention discloses a graphene-modified waterborne epoxy coating curing agent as well as a preparation method and application of the curing agent. The preparation method comprises the following steps: firstly dispersing graphene oxide prepared by virtue of an improved Hummers method into water, so as to obtain graphene oxide dispersion liquid; and adding a surfactant with amino end groups, uniformly mixing, carrying out microwave heating to enable graphene oxide to react with the surfactant, adding a graphene derivative water solution into a waterborne epoxy coating curing agent, and uniformly mixing, so as to obtain the graphene-modified waterborne epoxy coating curing agent. The graphene-modified waterborne epoxy coating curing agent is applied to the preparation of a bi-component waterborne epoxy coating, and the neutral salt spray test time of a formed anticorrosive coating can reach 185-252 hours.

The invention belongs to the field of aviation paint technology, and relates to a high-temperature-resisting aluminum paint used on steel surfaces, and a preparation method thereof. The paint is composed of three components with a weight ratio of 100:3-10:5-20. A component one is composed of a film-forming substance, a pigment and filling material, an auxiliary agent, and a solvent according to a weight ratio of 40-70:5-20:1-5:20-50. A component two is polyamide resin. A component three is aluminum powder slurry. The paint has a good heat resistance, good hardness, good solvent resistance, and good salt spray resistance. When a coating formed by construction is held for 5h under a temperature of 300 DEG C, the coating is well-preserved. The pencil hardness of the coating is no lower than 2H. During part assembly, the coating can hardly get scratched. Under a normal temperature, the coating is not changed after 60d in water and 60d in oil. With a salt spray test of 2000h, the comprehensive performance of the coating is determined as grade 1.

The invention provides a method for preparing chromium-free passivation solution, and a method for passivating an electrogalvanizing or zinc alloy layer by using the same, and relates to a method for preparing the passivation solution and a using method thereof. The method solves the problems that passivation of hexavalent chromium and trivalent chromium generates pollution, and white rust tested in a salt spray test has short time after the electrogalvanizing or zinc alloy layer is passivated by the passivation solution. The method for preparing the chromium-free passivation solution comprises the following steps: 1, preparing concentrated solution A; 2, preparing concentrated solution B; and 3, regulating pH value after the concentrated solution A, the concentrated solution B and deionized water are mixed, and heating or cooling the mixture to 20 to 60 DEG C to obtain the chromium-free passivation solution. The method for passivating the electrogalvanizing or zinc alloy layer by using the chromium-free passivation solution comprises the following steps: 1, secondarily passivating the electrogalvanizing or zinc alloy layer; and 2, aging the electrogalvanizing or zinc alloy layer to complete passivation on the electrogalvanizing or zinc alloy layer. After the electrogalvanizing or zinc alloy layer is passivated by the chromium-free passivation solution, the electrogalvanizing or zinc alloy layer is subjected to neutral salt spray test, and the white rust does not appears on the surface of a passivated film after 84-120 hours of continuous spraying.

The invention provides a method for preparing a temperature-resistant and corrosion-resistant aluminum oxide/organic silicon/silicon dioxide hybridized coating. The preparation method comprises the following steps of: preparing an organic silicon/silicon dioxide hybridized sol by using tetraethoxysilane as an inorganic phase precursor and methyl triethoxyl silane and diphenyl dimethyl silane as an organic phase precursor through a sol-gel method; preparing aluminum sol by using sec-butyl alcohol aluminum as an aluminum source through the sol-gel method; and then adding the aluminum sol into the organic silicon/silicon dioxide sol through a sol blending method, and preparing the aluminum oxide/organic silicon/silicon dioxide hybridized sol by using acetic acid as gel and a carbonyl-contained amide compound as a dry control chemical addition agent. The coating prepared by the invention has a good physical property. The hardness of the coating is 0.8825, the anti-impact intensity of the coating is 50 kg.cm, and the flexibility of the coating is 1 mm. The coating coated on an LY12 aluminum alloy plate is not destructive after being roasted at a temperature of 450 DEG C for 1 hour. The surface of the coating is non-corrosive after the coating salt spray test is carried out for 1368 hours.

The invention discloses a wear and corrosion resistant coating material and a preparation method thereof as well as a coating and a preparation method thereof, belonging to the technical field of thermal spraying. The coating material which is powder particles is prepared from the following components in percentage by weight: 85-87% of tungsten carbide powder, 8-11% of cobalt powder and 2-7% of cobalt powder, wherein the grain size distribution of the tungsten carbide powder is as follows: D97 is less than or equal to 0.9 mu m, D5 is greater than or equal to 0.4 mu m and D50 is 0.6-0.8 mu m. The free path d of a metal binding phase among the tungsten carbide powder grains is less than or equal to 0.5 mu m. The preparation method of the coating materiel comprises the following steps: adding deionized water, a defoamer and an adhesive into raw materials for mixing and ball-milling to obtain mixed slurry; spraying and drying the mixed slurry to obtain agglomerated particles; and then, sintering and crushing the agglomerated particles to obtain a WC-10Co4Cr coating material which is the wear and corrosion resistant coating material. The coating prepared from the coating material can bear a water pressure of 150MPa without leakage and is free from rust when neutral salt spray test resistance is longer than 672 hours.

Disclosed is a method of preparation of corrosion-resistant epoxy coatings. The coating composition contains two main corrosion resistant factors: The first one was Eemeraldine-Base polyaniline (EB-PANi), dissolved in the aminic hardener of epoxy. The other one was montmorrilonite clay, dispersed or exfoliated in the base component of epoxy resin. The hardener composition was prepared via dissolution of EB-PANi in functional amines like 3-(aminomethyl)-3,5,5-trimethylcyclohexan-1-amine adopting sonication and nanoscale filtering methods. The base component was prepared via gradual charging of MMT clay in epoxy resin via high-shear mixing plus sonication method. The morphology of the coatings during different stages of preparation was studied by optical microscopy and scanning electron microscopy and TEM. The corrosion-protective performance of the resultant coatings was evaluated by electrochemical impedance spectroscopy and salt spray tests. The results were compared with those of conventional epoxy zinc-chromate and neat resin coatings. Superior corrosion resistance was achieved via dissolution of 0.5-2.5 wt % of EB-PANi in the aminic hardener and 2-4 WT % of organomodified MMT in base component of coating.

A chromium(VI)-free, chromium(III)-containing and substantially coherent conversion layer on zinc or zinc alloys presenting, even in the absence of further components such as silicate, cerium, aluminum and borate, a corrosion protection of approx. 100 to 1000 h in the salt spray test according to DIN 50021 SS or ASTM B 117-73 until first attack according to DIN 50961 Chapter 10; being clear, transparent and substantially colorless and presenting multi-colored iridescence; having a layer thickness of approx. 100 nm to 1000 nm; and being hard, adhering well and being resistant to wiping.

The invention relates to a micro-arc oxidation treatment method of a heat-resistant cast rare earth magnesium alloy. The method has the advantages of simple equipment, low cost and no point discharge phenomenon. The heat-resistant cast rare earth magnesium alloy processed by the method has excellent corrosion resistance, when using the neutral salt spray (NSS) method in Corrosion-resistant testing method of the metal deposits and conversion coatings for the light industrial products of QB/T 3826-1999 for testing, taking sodium chloride solution with the weight percent of 5%, keeping the temperature constant at 35 DEG C plus or minus 1 DEG C and meeting the neutral salt spray-resistant test conditions, the heat-resistant cast rare earth magnesium alloy is rated nine grade according to Methods for corrosion testing of metallic and other inorganic coatings on metallic substrates-Rating of test specimens and manufactured articles subjected to corrosion tests of GB/T 6461-2002. The corrosion resistance is more than 96 hours.

The invention belongs to the technical field of metal surface treatment, and particularly relates to a trivalent chromium hard chromium electroplating solution and application of the trivalent chromium hard chromium electroplating solution in hard chromium electroplating. The electroplating solution is prepared from trivalent chromium main salt, a carboxylic acid or carboxylate complexing agent, a buffering agent, conducting salt and a catalyst. The deposition velocity reaches 2.5 micrometers/minute or above, the current efficiency reaches 36% or above, the thickness of an electroplating layer can reach 150 micrometers or above, each liter of the electroplating solution can be used for performing continuous electroplating for 900 ampere hours (an additive is supplemented during the process), high efficiency and high stability are maintained, the hardness of the electroplating layer reaches HV950 or above, and the electroplating layer has wear resistance the same as or similar to that of hexavalent chromium, has large binding force with steel, copper and copper alloy and is free of peeling or stripping or cracking in a 300 DEG C thermal shock test. As nanometer materials are added, corrosion resistance lasts for 150 h or longer in a neutral salt spray test. The trivalent chromium hard chromium electroplating solution has broad application prospects in the fields of rollers, hydraulic components, printing cylinders, shock absorbers, coal mine hydraulic supports and the like.

The invention relates to a chromium-free passivation solution used for continuous hot dipping coating of galvanized steel sheet, which belongs to the technical field of metal surface treatment and corrosion prevention. The compositions and the mixed ratio in one liter of the passivation solution are as follows: 3 to 5 grams of molybdate, 5 to 15 grams of tungstate, 3 to 5 grams of tannic acid, 5 to 20 grams of citric acid, 10 to 30 grams of hydrogen peroxide, 10 to 30 grams of silicate, 20 to 30 grams of pH value regulator, and the balance being water. The chromium-free passivation solution has the following advantages: as no chromium is contained, the chromium-free passivation solution has no effect on a human body and the environment, and has low cost which is equivalent to that of a chromate passivation solution and is approximately 30 percent of that of the chromium-free passivation solution used in the prior art, thus the cost is less than one tenth that of the chromium-free passivation solution containing 80 to 160 grams of the molybdate per liter and 16 to 32 grams of the tungstate per liter in the prior art; besides, the salt spray corrosion resistance of the passivated galvanized steel sheet can meet the requirement of national standard with the corrosion area of a 72-hour neutral salt spray test less than 5 percent; and the chromium-free passivation solution not only does not change the prior process conditions, but also does not change the prior equipment in use.

The invention discloses a composite surface protecting method for a neodymium-iron-boron magnet, comprising the following steps of: pretreating a neodymium-iron-boron magnet, electroplating or phosphating the pretreated neodymium-iron-boron magnet, spraying a corrosion-resistant coating on the surface of the electroplated neodymium-iron-boron magnet, pre-curing the sprayed neodymium-iron-boron magnet, curing the pre-cured neodymium-iron-boron magnet and performing vapour phase deposition on the cured neodymium-iron-boron magnet. The composite surface protecting method for the neodymium-iron-boron magnet has the following advantages that: the combining stability between the plating and the neodymium-iron-boron magnet and the corrosion-resistant property of the plating are improved by meansof the corrosion-resistant coating; the electroplating treatment and the spraying treatment are further enhanced by the vapour phase deposition; meanwhile, a circular hole structure of the neodymium-iron-boron magnet is further plated so that the integrated plating on the surface of the neodymium-iron-boron magnet is uniform; and the endurance time of the neutral salt spray test of the compoundedneodymium-iron-boron magnet can reach more than 300 hours.

The invention belongs to the field of metal materials, and particularly relates to an alloy proportion of a magnesium alloy with high corrosion resistance. The alloy material comprises components in percentage by mass as follows: 4.5%-5.5% of Al, 1.5%-2% of Zn, 0.1%-0.3% of Mn, 0.1%0.5% of Y as well as impurities, the impurities comprise elements as follows: smaller than or equal to 0.01% of Fe, smaller than or equal to 0.003% of Ni, smaller than or equal to 0.0004% of Cu, smaller than or equal to 0.03% of Si, smaller than or equal to 0.002% of Ca and the balance of magnesium. By means of Al, Mn, Zn and Y alloying scientific formula design, the corrosion resistance of the magnesium alloy is greatly improved with lower cost; and besides, 5% of NaCl contained neutral salt spray test is performed for 120 h, the corrosion rate v (agravity) is smaller than 0.008 mg*cm<-2>*h<-1>, and v (depth) is smaller than 0.5 mm/a.

The invention relates to a detection method of plated layer corrosion rate in a steel wire or a steel wire rope. The method comprises the process steps that: 1, a sample is prepared, wherein a plated steel wire or steel wire rope is cut into N segments; the surfaces are cleaned by using alcohol cotton; and the ends are sequentially sealed by using a solid sealant (AB composite adhesive), such that N samples are prepared; 2, the samples are weighed; 3, a salt spray test is carried out, wherein the weighed samples are subjected to a neutral salt spray test in a salt spray box; 4, the surfaces of the samples are cleaned, wherein the samples after the salt spray test are washed in a container with a prepared chromic acid cleaning agent, such that residual salt and corrosives on the surface of the samples are completely removed; the samples are washed by using water, and are dried; and 5, weighing and calculation are carried out, wherein the dried samples are weighed, and the weights are adopted as after-test weights; and the corrosion rate is calculated according to the weight loss before and after the test. With the method provided by the invention, corrosion-resistant rates of various plated layers can be easily determined, and the service lives of the plated layer samples in the environment can be inferred.

The invention discloses a zinc coat environmental-friendly passivation solution and a use method thereof. The passivation solution is formed by dissolving a solute consisting of a plurality of materials into deionized water, wherein the solute in the solution comprises the following components: 80-120g/L of sodium molybdate, 20-30g/L of sodium tungstate, 2-7g/L of titanyl sulfate, 5-10g/L of phytic acid, 15-50g/L of acrylic acid and 20-40g/L of hydrogen peroxide, wherein the pH value of the solution is regulated to 1.5-2.5 by using dilute acid. It is found that the zinc coat environmental-friendly passivation solution contains no chromium ions and thoroughly solves the problem of environment pollution brought by chromating; through salt spray test examination, a zinc coating plate passivated by the passivation solution has corrosion resistance approximately consistent with that of the traditional passivation solution; meanwhile, the use method is simple and easy.

The invention relates to a water base non-chrome zinc-aluminium coating and methods for preparing and using the same. The coating is prepared by proportionally mixing a component A and a component B; the component A contains 50-150g/L of lamellar metal powder, 145-290ml/L of organic solvent, 10-200ml/L of deionized water, 10-36ml/L of reducing agent and 5-15ml/L of wetting agent; and the component B contains 60-240ml/L of deionized water, 20-75ml/L of binding agent, 8-22ml/L of thickening agent, 4-8ml/L of silicon compound and the balance of the organic solvent. The method for preparing the water base non-chrome zinc-aluminium coating comprises the steps of: weighing the lamellar metal powder proportionally to be mixed uniformly, and then adding the organic solvent to be mixed uniformly for later use; mixing the reducing agent with the wetting agent, adding an appropriate amount of the deionized water to be mixed uniformly, and then adding the lamellar metal powder liquid to prepare the component A; proportionally weighing the thickening agent, the binding agent and the silicon compound, and adding the organic solvent to be mixed uniformly to prepare the component B; and mixing the prepared component A and the prepared component B according to the ratio of 2:1, and stirring unit uniform, thus obtaining the coating. The method for using the water base non-chrome zinc-aluminium coating is that the coating is coated on a part to be treated, and the baking temperature is increased to 360 DEG C so as to solidify and crosslink the coating to form a dense protective layer. The coating has the corrosion resistance which reaches 840 hours of a neutral salt spray test and over 96 hours of a heat resistance test, the usage amount of harmful substances is greatly reduced, and the working environment is improved.