Preparation method of nano-coating for reducing sea organism adhesion on titanium alloy surface

Abstract

The invention relates to a preparation method of a nano coating with reduced marine organism attachment on the surface of a titanium alloy, which comprises the following steps: enabling an electrolyte to contain sodium phosphate, sodium benzoate and boric acid and further contain a copper ammonia complex prepared from copper sulfate and ammonia water; performing conventional treatment on a titanium alloy, enabling the titanium alloy to serve as an anode, enabling a stainless steel plate to serve as a cathode, respectively controlling the working current, the duty ratio and the pulse frequency of a pulse power source at 10-20 A, 10-20% and 500-650 Hz, and controlling the temperature of the electrolyte at 50 DEG C; and electrolyzing for 5-30 minutes to generate a cuprous oxide Cu2O layer and a titanium dioxide TiO2 ceramic insulation coating having a nanocrystalline and non-crystalline structure on the surface of the titanium alloy, wherein the coating thickness is 5-50 mu m, the surface hardness is 400 hV, the bonding strength is 30 MPa, the insulation resistance is 1 Mohm, the 96h neutral salt spray corrosion test proves that no cracks and corrosion products are generated, the mass of the element copper in the coating is not less than 10%, and the marine organism attachment weight 3 months after hanging in marine water is not more than 20g / m<2>.

Description

Technical field [0001] The application belongs to the technical field of oxide coatings, in particular to a method for preparing a nano-coating for reducing the adhesion of marine organisms on the surface of a titanium alloy. Background technique [0002] Microarc Oxidation MicroarcOxidation is abbreviated as MAO. MAO is a new technology for in-situ growth of oxide ceramic coatings on non-ferrous metal substrates such as Al, Ti, Mg, Zr, Nb, Ta, etc. and alloy surfaces, without affecting the performance of the substrate Under the premise of improving the corrosion resistance and wear resistance of its surface, because the oxide ceramic coating has the characteristics of high bonding strength and good insulation, in the shipbuilding and marine industries, the use of MAO can be very different in complex shapes and wire sizes. A uniform and sufficiently hard coating is formed on large parts to prevent the copper, copper alloy, steel pipes, piping accessories and other parts in contac...

AI Technical Summary

Problems solved by technology

[0003] The commonly used electrolyte coating formula of MAO is phosphate, aluminate, silicate, glycerophosphate-acetate and sodium hydroxide solution system, and the prepared micro-arc oxidation coating does not have the ability to prevent marine organisms from adhering. For example, after three months of seawater hanging film test, the weight of marine organisms on the coating surface can reach 65-100g / m 2 , the greater the amount of marine organisms attached to the sea, the greater the blockage of the sea pipelines, pumps, valves and other components, and even cause serious corrosion in the joint gap, accelerate the corrosion damage of the base material, affect the normal use of the ship, and reduce the cost of the ship. safety and reliability

[0004] Chinese patent CN101311326A discloses an electrolyte and a micro-arc oxidation method for light metal micro-arc oxidation. The electrolyte contains 5-100g / L sodium hexametaphosphate, 2-100g / L sodium silicate, 0.1-10g / L Cobalt sulfate, 1-30g / L ammonium metavanadate, after micro-arc oxidation treatment, a micro-arc oxidation coating with good stain resistance, scratch resistance and compactness is obtained on the light metal surface, and has high hardness and wear resistance However, the micro-arc oxidation coating only has a certain antibacterial effect on single-celled organisms such as bacteria and fungi, and the ability to prevent marine organisms from adhering to light metal surfaces is very poor

[0005] So far, there are no relevant reports on the preparation method of nano-coatings that can reduce the adhesion of marine organisms on the surface of titanium alloys.

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