TW201418376A - Composite coating for preventing marine biofouling and spraying method thereof - Google Patents

Abstract

A composite coating for preventing marine biofouling and a preparation method thereof. The composite coating consists of a nickel-chromium transition layer of 80 μ m to 100 μ m, a composite insulation coating of aluminum oxide and titanium oxide of 180 μ m to 250 μ m, and a red copper antifouling coating of 800 μ m to 1000 μ m. The total thickness of the coating is 100 μ m to 1500 μ m. The method comprises: spraying the nickel-chromium transition layer and the composite insulation coating through a High Velocity Oxygen Fuel (HVOF) spraying method, and spraying the red copper coating through a cold spraying method.

Description

Composite coating for preventing marine biological fouling and spraying method thereof

The invention relates to a spraying method, in particular to a composite coating for preventing marine biological fouling and a spraying method thereof, and belongs to the technical field of spraying.

Marine hulls and components of ships navigating in the ocean are highly polluted by marine organisms and require regular cleaning of marine fouling. The commonly used antifouling treatment methods are painting coatings, including toxic antifouling coatings, non-toxic antifouling coatings, and low surface energy coatings for antifouling, but this method is used for antifouling treatment, which has short period of effect and requires frequent antifouling treatment. It caused a waste of manpower and material resources. There are also copper and copper alloy methods for anti-fouling. Copper and copper alloys release copper ions due to their own corrosion in seawater environment. They are often used in ship structures to prevent the growth of marine organisms. However, due to weak electrical insulation measures and materials, they cannot Plays a good antifouling effect.

Supersonic flame (HVOF) spraying technology is a kind of thermal spraying technology that appeared in the 1980s. It is a practical technology developed on the basis of other flame spraying technologies, and has been applied and promoted in the industrial field. The cermet coating strength prepared by the supersonic flame (HVOF) spraying technology is much higher than other thermal spraying interfaces, and the supersonic flame (HVOF) spraying technology has high flame speed, low temperature and high bonding strength. The coating composition does not decompose, the process is simple and convenient, and the like, and is particularly suitable for the spraying of cermet, so that HVOF technology has been widely used in cermet spraying. Although supersonic has some advantages, its deposition rate and deposition efficiency are relatively low and relatively high in cost.

Cold spray technology, also known as cold aerodynamic spraying, refers to a method in which a high-speed solid particle having a certain plasticity collides with a substrate and is deposited by a strong plastic deformation to form a coating. The process utilizes a comprehensive selection of particle temperature, velocity and size to make it as low as possible Spray at the temperature. In the cold spray process, the powder particles are accelerated by the supersonic flow at a temperature lower than the melting point of the material, and thus the particles forming the coating are solid, thereby avoiding the harmful effects in the conventional thermal spraying method, such as high temperature oxidation and evaporation. Dissolution, crystallization, residual stress, stripping, gas release, and other common problems can be minimized or eliminated. Compared with the thermal spraying technology, the cold-sprayed particles are not melted, the thermal influence of the coating on the substrate is small, the thermal stress of the coating and the substrate is reduced, and the stress between the layers of the cold-sprayed layer is low, and mainly the compressive stress is favorable. To deposit a thicker coating.

At present, the underwater hull and components of ships sailing in the ocean are very serious, and the traditional method can not achieve the purpose of anti-fouling treatment, and the traditional method has short anti-pollution period and is prepared by supersonic flame spraying. The transition layer and the insulating layer have strong bonding force with the substrate, and the bonding strength is greater than 35 MPa. When the cold spraying technology is used, the copper is not oxidized, the antifouling effect of the copper can be ensured, and the thermal spraying technology and the cold spraying technology are rationally utilized. Can overcome the shortcomings of traditional methods and achieve remarkable results.

The object of the present invention is to provide a composite coating for preventing marine biofouling and a spraying method thereof, which adopts supersonic flame spraying technology and cold spraying technology to surface-treat the structure of the original component to achieve good marine biological antifouling effect. .

In order to achieve the object of the present invention, the composite coating for preventing marine biofouling provided by the present invention is composed of a transition layer: a nickel-chromium layer of 80-100 μm, a composite coating of aluminum oxide and titanium oxide of 180-250 μm. The layer is composed of a 800~1000μm copper antifouling coating with a total coating thickness of 1000~1500μm.

Another object of the present invention is to provide a spraying method for the above composite coating, which comprises the following steps: (1) metal substrate surface pretreatment: using abrasive blasting to remove Surface oxide layer And other debris, reaching Sa2.5 or above; (2) supersonic flame spraying: using a supersonic flame spraying method, spraying a nickel-chromium (Ni-Cr) transition layer on a sandblasted metal substrate, spraying a thickness of 80 ~100μm, then spray alumina and titanium oxide composite insulating coating on the transition layer, the thickness of the coating is 180~250μm; (3) cold spraying: spray the anti-fouling coating copper on the surface of the insulating coating by cold spraying The powder has a thickness of 800 to 1000 μm.

The beneficial effects of the present invention over the prior art are:

(1) Using supersonic flame spraying, the prepared transition layer and insulating layer have strong bonding force with the substrate, and the bonding strength is greater than 35 MPa.

(2) When the cold spray technique is used, the copper is not oxidized, and the antifouling effect of the copper can be ensured.

(3) The composite coating of the designed transition layer, the insulating layer and the antifouling functional layer can electrically insulate the anti-fouling functional coating between the metal substrates and fully exert the antifouling effect.

(4) Scope of application: It can be used for anti-fouling of underwater structures of ships, such as hull, submarine grille, propeller, etc.

The invention is further illustrated by the following examples, which are intended to illustrate the invention and not to limit the scope of the invention.

Example 1 Antifouling of Submarine Grille

A composite coating for preventing marine biofouling and a spraying method thereof, comprising the following steps: (1) Surface pretreatment of metal substrate: abrasive blasting is used to remove oxide layer and other impurities on the surface of the seafloor grid to reach Sa2.5 level (2) Supersonic flame spraying: using a supersonic flame spraying method, spraying a nickel-chromium (Ni-Cr) transition layer on a sandblasted metal substrate, spraying a thickness of 80 μm, and then Alumina and titanium oxide composite insulating coating was sprayed on the transition layer to a thickness of 250 μm; (3) Cold spraying: a copper powder was sprayed on the surface of the insulating coating by a cold spraying method to a thickness of 800 μm.

Example 2 Antifouling of a propeller

A spraying method for a composite coating for preventing marine biofouling comprises the following steps: (1) pretreatment of a metal substrate surface: sandblasting with an abrasive (such as copper ore) to remove oxide layer and other impurities on the surface of the propeller to reach Sa2 .5 or above; (2) Supersonic flame spraying: a supersonic flame spraying method is used to spray a nickel-chromium (Ni-Cr) transition layer on a sandblasted metal substrate, spraying a thickness of 100 μm, and then spraying on the transition layer. Alumina and titanium oxide composite insulating coating, spray thickness of 180μm; (3) cold spray: cold spray method, spray antifouling coating pure copper powder on the surface of the insulating coating, the thickness is 1000μm.

Example 3 Anti-pollution of underwater hull

A spraying method for a composite coating for preventing marine biofouling comprises the following steps: (1) Surface pretreatment of a metal substrate: abrasive blasting is used to remove oxide layer and other impurities on the surface of the underwater hull steel plate to reach Sa2.5 level (2) Supersonic flame spraying: using a supersonic flame spraying method, spraying a nickel-chromium Ni-Cr transition layer on a blasted metal substrate, spraying a thickness of 90 μm, and then spraying alumina and titanium oxide on the transition layer. Composite insulating coating, spray thickness of 200μm; (3) cold spray: cold spray method, spray antifouling coating pure copper powder on the surface of the insulating coating, the thickness is 900μm.

Claims (2)

A composite coating for preventing marine biofouling, characterized in that the composite coating consists of a nickel-chromium Ni-Cr transition layer of 80-100 μm, a composite coating of alumina and titanium oxide of 180-250 μm, and a composite coating of 800-1000 μm. The composition of the copper antifouling coating has a total coating thickness of 1000 to 1500 μm. A spraying method for preventing composite coating of marine organisms, comprising the following steps: (1) pretreatment of metal substrate surface: using abrasive blasting to remove oxide layer and other impurities on the surface of the component to reach Sa2.5 level or higher; (2) Supersonic flame spraying: using a supersonic flame spraying method, spraying a nickel-chromium Ni-Cr transition layer on a blasted metal substrate, spraying a thickness of 80-100 μm, and then spraying aluminum oxide and titanium oxide on the transition layer. Composite insulating coating, spraying thickness is 180~250μm; (3) Cold spraying: using cold spraying method, spraying antifouling coating copper powder on the surface of insulating coating, the thickness is 800~1000μm.