4 results about "Chromium phosphate" patented technology

This application provides a wide-temperature-range modified phosphate-based self-lubricating coating, its preparation method, and its application. The method includes: adding CrO3 solution to polyphosphoric acid at 90°C under stirring, adding Al(OH)3 in batches, continuing stirring for 2-3 hours, and cooling to room temperature to obtain a chromium-aluminum phosphate adhesive; heating the chromium-aluminum phosphate adhesive to 110-120°C, adding fumed silica, stirring, and then adding B2O3 in batches to obtain a modified chromium-aluminum phosphate adhesive; preparing the wide-temperature-range modified phosphate-based self-lubricating coating: mixing the modified chromium-aluminum phosphate adhesive with silica sol, mixing evenly, and then adding deionized water and filler to obtain a wide-temperature-range modified phosphate-based self-lubricating coating; spraying the wide-temperature-range modified phosphate-based self-lubricating coating onto the substrate surface and sintering to form a wide-temperature-range modified phosphate-based self-lubricating coating. The self-lubricating coating provided by this application can be applied to the field of wide-temperature-range self-lubrication and corrosion protection from room temperature to 800°C.

The application discloses a wide-temperature-range high-temperature-resistant self-lubricating composite coating and a preparation method thereof, and belongs to the technical field of high-temperature lubricating coating. The coating is composed of a chromium aluminum phosphate-based binder and a composite functional filler, wherein the mass ratio of the chromium aluminum phosphate-based binder to the composite functional filler is (0.5-2):1; the composite functional filler is composed of dimolybdenum ditelluride and rare earth oxide, the dimolybdenum ditelluride accounts for 30-80% of the total mass of the composite functional filler, and the rare earth oxide accounts for 20-70%. The application further provides a preparation method of the coating, which comprises mixing raw materials to prepare a coating slurry, coating the coating slurry on the surface of a substrate, and obtaining the coating through stepwise solidification. Through the synergistic effect of the dimolybdenum ditelluride and the rare earth oxide, the coating has excellent lubricating performance and high-temperature stability in a wide temperature range from room temperature to 900 DEG C, the friction coefficient is stable below 0.3, the bonding strength with a metal substrate is high, the preparation process is simple, and the coating can be widely applied to high-temperature moving parts in the fields of aerospace, gas turbines, metallurgy and chemical industry.

This invention discloses a gas-liquid dual-repellent anti-corrosion composite coating for magnesium-aluminum alloy surfaces and its preparation method. The method includes: immersing a pretreated magnesium-aluminum alloy with α-phase and β-phase microstructures into a phosphate-chromium salt mixed etching solution under no applied current conditions; selectively etching using the natural potential difference between the two phases; preferentially dissolving the α-phase to construct micron-level "valleys" while simultaneously depositing a phosphate-chromium salt conversion film in situ covering the surface of the continuous network of β-phase "peaks," resulting in a tightly interwoven "peak-valley" multi-level micro / nano composite structure; subsequently, immersing it in an ethanol solution containing fluorinated silane for treatment; and drying to obtain the composite coating. This coating has an integrated structure with the substrate, possessing excellent gas-liquid dual-repellent properties, long-term anti-corrosion performance, and good mechanical stability. This invention features a simple process, low cost, and safe and controllable operation, making it suitable for applications such as corrosion protection in marine equipment and underwater transmission components, and has great potential for industrial application.

The application discloses a preparation method of a high-efficiency environment-friendly chromium phosphate passivation solution, and comprises the following steps: stirring and reacting a chromium phosphate solution, an oxidizing agent and a complexing agent to obtain component A; adding a film forming promoter and a stabilizer into deionized water and heating to obtain component B; slowly adding the component A into the heated component B, mixing, heating and stirring, and filtering to obtain a chromium phosphate passivation solution product. The chromium phosphate passivation solution has excellent passivation effect, can form a dense and uniform passivation film on a metal surface, effectively improves the corrosion resistance of the metal, prolongs the service life of the metal, and has a neutral salt spray resistance time of more than 100 hours. The trivalent chromium in the passivation film will not produce hexavalent chromium to cause harm to the environment with the lapse of time. The preparation method of the chromium phosphate passivation solution is simple, raw materials are easy to obtain, the cost is low, and the method is suitable for industrial production and has good environmental protection performance. The chromium phosphate passivation solution does not contain harmful hexavalent chromium, and harm to the environment and human bodies is reduced.