422 results about "Chromic anhydride" patented technology

The invention discloses a coloring liquid and a coloring method for chemically coloring a 304 stainless steel surface into black, belonging to the technical field of stainless steel surface treatment, aiming to coat a back film layer on the 304 stainless steel surface, mainly solving the problem that a colored film has poor uniformity and repeatability, and being used for improving the decorative performance, wear resistance and corrosion resistance of stainless steel. The invention mainly includes the prescription of the coloring liquid and the coloring method for coloring the 304 stainless steel surface into black, wherein the coloring liquid mainly comprises main film-forming agents (chromic anhydride and chromium sulfate), an assistant filming-forming agent (sulfuric acid), additives (ferric sulfate, manganese sulfate and cerous sulfate) and water; and the coloring method mainly comprises the steps of electrolysis pretreatment, chemical coloring and hole sealing post-treatment, wherein potential control is adopted in the coloring process. A black stainless steel film obtained by using the coloring liquid and the coloring method has the advantages of uniform colored film, no obvious color difference, bright color, excellent wear resistance and corrosion resistance, good film adhesion, simple and practical coloring method, easily controlled coloring process, good color repeatability and the like.

The invention provides an oxidation prevention process used for lithium ion battery copper foil. The method comprises the steps that a semi-finished copper foil product which is not oxidized is introduced into an anti-oxidation passivation solution to be soaked, then squeezed dry through a squeeze roll, dried through hot air of an oven and directly wound, and a copper foil product is obtained after the oxidation prevention process. The anti-oxidation passivation solution comprises, 100-200 g/m<3> of benzotriazole, 0-1000 g/m<3> of chromic anhydride, 0.1-2 g/m<3> of rare earth metals of phosphoric acid, 0.1-2 g/m<3> of organic silane coupling agents, 10-30 L/m<3> of ethyl alcohol, and the balance water. The pH value is adjusted to be 5.5-8.5 through alkali such as sodium hydroxide and potassium hydroxide. The process is free of pollution to the environment; an anti-oxidation film of the produced copper foil product is moderate, even and consistent in thickness; the copper foil product is high in electrical conductivity and wettability, and the properties of the capacitance, the number of times of charge and discharge and the service life of a lithium ion battery can be effectively improved.

The invention relates to a de-coating liquid that includes vitriol and oxidant that includes at least from hydrogen peroxide, potassium permanganate, potassium dichromate and chromic anhydride. It also includes reserve salt inter-nitrobenzene sodium xanthate, and accelerating agent copper sulphate. It could effectively decrease the adverse effect of the plastic itself and could decrease environment pollution and decrease harm to human, etc.

The invention relates to an electrolytic polishing solution for a magnesium alloy medical heart stent and a surface polishing processing technology of the medical heart stent. The electrolytic polishing solution for the medical heart stent is prepared from alcohol and acid. The magnesium alloy surface polishing processing technology of the medical heart stent comprises the first step of mechanical grinding and polishing, the second step of oil and dirt removing, the third step of ultrasonic vibrating and alkali washing, the fourth step of electrolytic polishing, the fifth step of ultrasonic vibrating and alcohol washing and the sixth step of drying and vacuum sealing storage. A product obtained through the fifth step is dried, and a finished magnesium alloy heart stent with the bright mirror surface is obtained and is stored by a vacuum package bag in a sealed manner. By means of the technical scheme, firstly, chromic anhydride large in toxicity and serious in pollution is not contained, the processing difficulty of the waste polishing solution is lowered, the environment pollution is reduced, and the polishing solution is environmentally friendly; secondly, the requirement of the polishing technology for the temperature range is not high, the effect of polishing the bright mirror surface can be achieved under the room temperature, and therefore the operation cost is greatly reduced; and thirdly, reaction time is short and is 1-10 min. Compared with a traditional polishing technology, the polishing electrolysis time can be greatly shortened, and accordingly energy consumption is effectively reduced.

The invention relates to a surface processing technique for the bacterium resistance, the erosion resistance and the tarnish resistance of aluminum or aluminum alloy material, comprising the following steps: firstly, degreasing processing is carried out on an aluminum material used as a workpiece, the aluminum material after being degreased is put into an acid solution, the workpiece is used as one pole, an aluminum plate or a lead plate is used as the other pole and is electrified with alternating current, the liquid temperature is kept between 0 DEG C and 30 DEG C, an oxidation film with bacterium resistance, erosion resistance and tarnish resistance is formed on the surface of the aluminum material after oxidation for 10-30 minutes, and finally, the workpiece is taken out and placed in purified water of 90-100 DEG C and closed for 15-20 minutes. The acid solution has the components and the content that each liter of acid solution contains 80-150 grams of industrial grade sulfuric acid, 2-10 grams of chromic anhydride and 0.1-1.5 grams of water soluble silver salt. The surface of the aluminum material after being processed by the invention is provided with a layer of oxidation film, silver compounds with bacterium resistance and tarnish resistance, such as silver chromate, silver dichromate and the like, are formed in the film, then the film is closed by hot water, and the erosion resistant performance is more excellent.

The invention discloses chemical grinding and polishing fluid which comprises the following components: 1-15 percent by weight of sulfuric acid solution, 10-50 percent by weight of hydrogen peroxide solution, 3-15 percent by weight of stabilizing agent, 0.1-5 percent by weight of wetting agent and 2-12 percent by weight of leveling agent. Compared with the prior art, the chemical grinding and polishing fluid disclosed by the invention does not contain nitric acid, chromic anhydride and other toxic and harmful substances and cannot harm the human body health and cause the pollution to an environment in the grinding and polishing processes; the grinding and polishing processes are performed at a normal temperature without heating, so that the energy consumption of chemical reaction is greatly reduced.

The invention discloses a chemical oxidation method of surfaces of aluminum and aluminum alloys. The chemical oxidation method comprises the following working procedures of: oil removal, primary water-washing, primary bright-dipping, alkaline corrosion, secondary bright-dipping, conductive oxidation, secondary water-washing and drying, wherein a solution used in the conductive oxidation working procedure comprises the following component of: 3-7g/L of chromic anhydride, 1-4g/L of sodium fluoride and 0.5-2g/L of potassium ferricyanide, the solution temperature is 15-60 DEG C and the oxidation time is 5-20min. The chemical oxidation method disclosed by the invention has the advantages that: in the oxidation process, the solution is prepared according to the proportions of the chromic anhydride to the sodium fluoride to the potassium ferricyanide of (3-7): (1-4): (0.5-2(g/L)), the solution temperature is controlled at 15-60 DEG C, and the oxidation time is controlled to 5-20min, therefore protection layers generated on the surfaces of aluminum and aluminum alloy parts and component not only have better protection performance, but also have favorable electric conduction function and meet functional requirements of multiple products.

The invention discloses a colored stainless steel manufacturing method, including that the stainless steel is submerged in a coloring pool containing the chromic anhydride solution and the sulphuric acid solution for generating the light interference oxide film; the potential difference between the stainless steel and the reference electrode, which is read out by a millivolt potential instrument, is outputted to an A/D switching circuit by an output interface, the A/D switching circuit outputs the switched digital type potential difference to a computer which monitors the change of the potential difference by a control program, when the potential difference reaches the preset value, the computer sends out indicator signals for taking the stainless steel out of the coloring pool. By the invention, the light interference film with various colors such as sapphire, champagne gold, tawny, atroceruleous, amaranth, hyacinth, purple green, green, etc. can be steadily and reproducibly acquired.

The invention relates to a method for chroming a stainless steel conductive roller. The method comprises roller body surface polishing, oil removing, cleaning, roughing and peak clipping treatment and is characterized by comprising the following steps of: adding 135+/-10 grams of nitric acid (HNO3), 165+/-5 grams of hydrogen chloride (HCl), 30+/-3 grams of hydrogen fluoride (HF) and 2 grams of hexamethylene tetramine (C6H12N4) sequentially into 770 millimeters of water; stirring the mixture uniformly; preparing peak-clipping burr-removing liquid at normal temperature; scrubbing the surface of the roughened layer of the conductive roller for 15 to 20 minutes by using the peak-clipping burr-removing liquid; preparing chroming liquid in a ratio of chromic anhydride (CrO3) to sulfuric acid (H2SO4) of 100 to 1.15; and after washing the stainless steel conductive roller cleanly, placing the cleaned stainless steel conductive roller into a horizontally chroming tank to power on and perform electroplating. The method has the advantages of: by a peak-clipping burr-removing liquid corrosion method, the problem that waste edges and scraps after the roughing process are difficult to remove due to high toughness of stainless steel is solved and the chromed stainless steel conductive roller does not scratch the surface of a steel plate due to the burr; a chroming layer is bonded with a matrix firmly by the electroplating process, so the chroming layer does not fall off and has high wear resistance; the stainless steel conductive roller has a long service life, a short repair cycle of only 2 to 3 days and cost of one fifth of that of a copperized conductive roller.

The invention solves a technical problem of providing a stainless steel shell surface treatment method having short processing period, nontoxic processing and a beautiful shell after treatment. The stainless steel shell surface treatment method comprises the following: (1) a step of liquid shot blast, in which glass microballoons and water are mixed with a 10 to 15g/L corrosion inhibitor for shot blast according to a principle that the ratio of the microballoons to the water is between 1 to 5 and 1 to 8; (2) a step of passivation, in which a stainless steel shell is soaked in a 300 to 350g/L concentrated nitric acid or a 5 to 50 g/L dilute solution of chromic anhydride; and (3) sealing, in which confining liquid is spread on the surface of the stainless steel shell and then dried. The method has cost lower than that of the prior surface treatment technique and can effectively remove scale generated during welding; the appearance of the stainless steel shell is a mat surface which is fine and elegant and has strong dirt resistance and prevents hands touching the surface from leaving impression; and the process does not generate toxic substances and is good for health and environment protection. The method is particularly suitable for surface treatment of stainless steel shells of storage batteries.

The invention discloses new technology for plating golden yellow on an automotive hub, which comprises the technical steps: galvanizing, pre-plating copper, brightly plating copper, plating nickel, plating golden yellow, and the like. The chemical composition formula contained in each L of plating solution is that: galvanizing solution comprises 220 to 240g of potassium chloride, 40 to 55g of zinc chloride, 30 to 35g of boric acid, and 15 to 25ml of brightener; copper pre-plating solution comprises 70 to 85g of copper phosphate, 280 to 350g of phosphor copper potassium, 4 to 6ml of ammonia water, and 3 to 5ml of brightener; the bright copper plating solution comprises 200 to 220g of copper sulfate, 70 to 90g of sulfuric acid, 0.06 to 0.08g of chloride ion, and 4 to 8ml of brightener; nickel plating solution comprises 260 to 300g of nickel sulfate, 30 to 50g of nickel chloride, 30 to 40g of boric acid, 0.6 to 1ml of brightener, 8 to 12ml of softening agent, and 2 to 4ml of wetting agent; and golden yellow plating solution comprises 120 to 140g of imitation gold salt and 2 to 4ml of ammonia water. After the plating, water washing and drying are performed, and a polyurethane paint is sprayed on the surface of the automotive hub. The new technology for plating golden yellow on the automotive hub radically eliminates the damage and environmental pollution of sodium cyanide and chromic anhydride to human bodies; the plated golden yellow automotive hub is luxurious and attractive, has strong corrosion resistance, and is suitable for high-class automotive assembly.

The invention relates to a method for removing hydrogen in high strength steel electroplated by zinc-nickel alloy, including the following steps: 1) zinc nickel alloy coated high strength steel parts are sequentially cleaned by water and soaked by alcohol; 2) parts after being cleaned are placed into a vacuum furnace to be subject to heat treatment, so that hydrogen atom on coating surface is overflown; 3) parts after hydrogen removal are placed into citric acid-boric acid mixed aqueous solution to be activated; 4) parts after coating activation treatment are subject to zinc nickel alloy electroplating again; 5) parts after composite electroplating are placed into chromic anhydride-sodium chloride mixed aqueous solution to be passivated; 6) parts after passivation treatment are cleaned by water and dried by blowing, thus obtaining the finished product conforming to the requirements. The method can be utilized to effectively remove hydrogen penetrated into base metal in electroplated by zinc-nickel alloy process, hydrogen embrittlement is reduced, and passivation coating with good protective properties can be generated on the surface of alloy coating, and meanwhile the technological method of the invention is simple and production cost is low.

The invention discloses a bright electrochromism technique for a cold-rolled steel strip. The technique is characterized by comprising the following steps: (1) electroplating a chromium layer, wherein the plating solution comprises the following components: 100-160 g/L of chromic anhydride, 1.5-3.0 g/L of NH4F, and 0.5-1.5 g/L of mixed rare-earth additive; the temperature of the plating solution is between 25 and 40 DEG C; the current density is between 25 and 70 A/dm<2>; and the electroplating time is between 10 and 20 s; and (2) electroplating and oxidizing the chromic layer, wherein the plating solution comprises the following components: 50-75 g/L of chromic anhydride, 0.8-2.5 g/L of NH4F, and 5-15 g/L of NaOH; the temperature of the plating solution is between 15 and 30 DEG C; the current density is between 8 and 20 A/dm<2>; and the electroplating time is between 2 and 6 s. In the invention, the performance advantages of the plating solution are fully used to obtain a uniform chromium-plated plate with bright plating layer and good quality, thus further improving the surface quality of the chromium-plated plate. Meanwhile, the method has the advantages of low corrosion to equipment, low temperature and effective reduction of energy consumption.

The invention discloses a method for detecting chloride ion impurities in a high concentration chromic anhydride solution, which comprises the following steps of dispensing the high concentration chromic anhydride solution to be detected to be placed in a titration glass, dropwise adding an alkaline adjusting solution into the chromic anhydride solution under the uniform stirring of an automatic potentiometric titrator, adjusting potential of hydrogen (pH) value of the solution to be detected to 4.5 to 5, then setting the maximum jumping point detected by the automatic potentiometric titrator as a titration end point, starting the automatic potentiometric titrator, titrating by a silver nitrate standard solution, performing blank titration of corresponding reagents, and calculating content of chloride ions according to a standard formula. The alkaline solution is a 25% sodium hydroxide solution, and the concentration of the silver nitrate standard solution is 0.0400mol/L. The method for detecting chloride ion impurities in the high concentration chromic anhydride solution has the advantages that the conventional automatic potentiometric titrator is used, adjustment is performed by addition of the sodium hydroxide solution, extreme influences of solution color on the detection are eliminated, quantitative detection of the chloride ion impurities in the high concentration chromic anhydride solution which is repeatedly used is achieved, and the rapid detection requirement in the industrial production process is met.

The invention discloses a method and a device for purifying and recycling a chromium electroplating solution and a waste solution thereof. The method directionally solves the problem of metal pollutions and comprises the following steps: adopting a purification apparatus to effectively eliminate various harmful metallic impurities such as copper, zinc, nickel, iron and the like; concentrating the solution after the purification; and finally recycling the solution into an electroplating bath, wherein the recycling rate reaches more than 95 percent. Simultaneously, through an automatic control system, the electroplating bath, a recovery tank, the purification apparatus, a concentrating device, an analysis meter and the like are combined together organically to achieve full automatic operation. The method and the device solve the problem that the chromium electroplating solution cannot be recycled in clean production for years in China. The method avoids a large quantity of chromium-containing wastewater discharges, effectively saves additional supplementation of chromic anhydride at the same time, and obtains double produce effects of recycling economy and clean production.

The invention discloses a thermal spraying coating sealing agent, a preparation method and a use method, comprising aluminum chromium phosphate and filler in a weight ratio of 10:1-3; the aluminum chromium phosphate comprises 95-105 parts by weight of phosphoric acid , 23-26.5 parts of aluminum hydroxide, 9.5-11.5 parts of chromic anhydride and 4-6 parts of methanol, and the filler is Cr ₂ o ₃ . Mix phosphoric acid and chromic anhydride, stir in water bath at 70-90°C until fully dissolved; then add aluminum hydroxide and stir until fully dissolved; then slowly drop methanol to make it fully react, and bathe in water at 70-90°C for 15- 25min, obtain dark green viscous aluminum chromium phosphate solution; Add Cr ₂ o ₃ The filler is uniformly dispersed in the aluminum chromium phosphate solution to obtain the sealing agent. After the system is solidified, as the temperature continues to rise, there will be no thermal effect in the system within 1000 ° C. Aluminum chromium phosphate has good high temperature resistance. The raw material of the sealing agent of the invention is cheap and easy to obtain, the application process is simple, the operation is convenient, and the sealing period is short.

This invention discloses an oriented silicon steel insulation coating, which can be used to improve the performance of the laminated sheet . It has the composition weight percentage as follows: polyether-modified silicon oil, the water solution with 1% weight proportion, accounts for 0.01%-2.0%, of which the radio of hydrophilic chains to hydrophobic chains ranges from 20/80 to 100/0; aluminium dihydrogen phosphate 3%-24%, colloidal silica 4%~16%, chromic anhydride 0.15%~4.50% and the rest is water. After coated in the oriented electrical steel, the said insulation coating can remarkably enhance the laminated sheet times by the intrinsic lubricity of silicone during the machining of oriented silicon steel, and hence greatly enhance the production efficiency. Besides, due to the favorable water-solubility of the polyether-modified silicon oil and the common heat-resistance of the silicone products, the said coating is easily prepared, uniformly coated, and has good dispersibility. The coated surface is in good quality, able to endure sintering with high temperature without thermal degradation.

The invention relates to a rust remover for steel precise components and a rust removing technology. The rust remover is composed of the following compositions in percent by weight: 15% of chromic anhydride, 15-17% of phosphoric acid, 1-1.2% of sulfuric acid and 66.8-69% of water. The rust removing technology comprises: immersing a steel precise component subjected to cleaning and oil removing into a solution of the rust remover, heating to 80-90 DEG for about 30-40 min; taking out and flushing with tap water for 1 min, and then immersing in a sodium carbonate aqueous solution with a concentration of 0.5% for about 5 min; taking out and immersing in a passivating solution composed of a sodium nitrite aqueous solution with a concentration of 10% and a sodium carbonate aqueous solution with a concentration of 0.5% according to a ratio of 50%:50%, heating to 80-90 DEG C for about 5-10 min; and taking the steel precise component out from the passivating solution, and flushing with tap water, wiping to dry and sealing with oil. The beneficial effects comprise that the technology is simple, and the rust remover has no any influence on dimension, shape, surface glossiness and precision on the steel precise component, and is good in ruse removing effect.