39results about How to "Stable corrosion resistance" patented technology

The invention relates to a low-cost, high-performance corrosion-resistant steel bar and a preparation method thereof. The low-cost, high-performance corrosion-resistant steel bar comprises the following chemical components by weight percent: 0.06-0.10wt% of C, 3-8wt% of Cr, 0.5-1wt% of Cu, 0.5-1.5wt% of Mn, 0.01-0.02wt% of N, not more than 0.03wt% of P, not more than 0.035wt% of S, 0.2-0.5wt% of Si and the balance of Fe and inevitable impurities. The preparation method comprises the steps of desulphurization pretreatment of molten iron, smelting by an electric furnace or a top and bottom combined blown converter, refining out of the furnace, continuous casting, heating of a casting blank, rolling and air-cooling by a cold bed. The low-cost, high-performance corrosion-resistant steel bar provided by the invention has the advantages of excellent corrosion resistance, relatively low cost and good mechanical properties, fatigue performance and welding performance.

The invention belongs to the technical field of metallurgy, and particularly relates to high-temperature aluminum and zinc liquid corrosion resisting alloyed gray pig iron and a smelting technology thereof. The high-temperature aluminum and zinc liquid corrosion resisting alloyed gray pig iron specifically comprises following elements including, by weight percent, 3.1%-3.3% of C, 1.9%-2.2% of Si,0.8%-1.0% of Mn, smaller than or equal to 0.06% of P, smaller than or equal to 0.03% of S, 0.15%-0.3% of Cr, 0.05%-0.15% of Ni, 0.05%-0.2% of Cu, 0.15%-0.25% of Mo, 0.02%-0.04% of light rare earth andthe balance Fe. Through the synergistic effect of electrolytic copper, chromium, nickel, ferromolybdenum, the light rare earth and other alloy elements, the content of pearlite in a base body is increased, the pearlite layer sheet thickness and sheet distance are obviously reduced, base body structure grains are fine, a graphite sheet formed through one-time crystallization is fine and disperse,a small number of ferrite base body structures are easily obtained, hardness can be better reduced, material toughness is improved, the metallurgical quality is good, and strength is high.

The invention discloses a method for judging the surface chromium metal content of a chromium-plated plate. The method comprises the following steps that: firstly, selecting a chromium-plated plate specimen; removing a chromium oxidation layer on the surface of the chromium-plated plate specimen; then, taking the chromium-plated plate specimen as an anode and a platinum wire as a cathode, carryingout constant current electrolysis in electrolyte sodium carbonate solution, recording a voltage value, marking voltage at the beginning as E1, along with electrolysis reaction, raising the voltage, subsequently, sharply increasing the voltage, when the voltage hardly changes, finishing electrolysis, finishing electrolyzing all surface metal chromium layers of the chromium-plated plate specimen, and recording voltage E2; and finally, calculating a voltage difference [Delta]E=E2-E1 before and after electrolysis to realize the semi-quantitative analysis of a chromium-plated amount of the surfaceof the chromium-plated plate. By use of the device, the measurement of the surface chromium-plated amount can be carried out on any position of the surface of the chromium-plated plate, and the distribution evenness of the surface metal chromium of the chromium-plated plate can be accurately judged.

An antistatic paint is prepared through mixing ethyl n-silicate with absolute alcohol, stirring, alcoholysis reaction, dropping hydrochloric acid diluted by purified water to make pH=2-3, laying aside, adding organic silanamine, stirring, adding zinc powder and stirring. Its advantages are high electrostatic conductivity and corrosion resistance, low cost, fast dry, and high firmness of film.

The invention provides a colorful trivalent chromium passivation liquid. A plurality of raw materials are dissolved in deionized water to form the passivation liquid. The passivation liquid comprises the following components by a ratio: 5-9 g / L chromium sulfate hexahydrate, 2-4 g / L cobalt sulfate heptahydrate, 4-8 g / L sodium chlorate, 2-3 g / L ammonium fluoride, 1-2 g / L of nitric acid, 2-3 g / L citric acid, and the balance of water. The resulting passive film has good corrosion resistance, the time can be up to 120 hours or more in a salt spray test, the surface has no any white rust or white spots, the porosity is low, and a blocking agent does not need to be used for treating.

The invention provides an aluminum and aluminum alloy passivation solution, preparation method and using method thereof; the raw material ratios of the passivation solution are as follows: 3-5g / L of zinc chromate, 0.5-1g / L of cobaltous sulfate, 2-3g / L of zirconium sulfate, 0.5-1.5g / L of sodium fluoride, 2-4g / L of nitric acid, 1-2g / L of citric acid, and the rest amount is water. A passivation working solution (bath solution) which is prepared by diluting the passivation solution is stable, low concentration, fast in passivation speed, low void ratio of the obtained passivation film, is able to form a yellow chromate film layer on surface of the aluminum product, has an excellent anti-corrosion property, and is able to greatly increase the paint or coating layer adhesive force on the work piece. The property of the formed passivation film for resisting neutral salt mist is more than 120 hours.