CN201567375U - Anti-corrosion coating on magnesium alloy surface - Google Patents

Abstract

An anti-corrosion coating on the surface of a magnesium alloy is arranged on a magnesium alloy substrate, a polysiloxane modified fluorocarbon coating is arranged on the outer surface of the magnesium alloy substrate, and a polysiloxane modified fluorocarbon coating is arranged on the magnesium alloy substrate and polysiloxane modified fluorocarbon Silicone coatings are provided between the coatings. The utility model solves the problem of weak bonding force between the fluorocarbon coating and the magnesium alloy substrate. Because the polysiloxane modified fluorocarbon coating has excellent durability and corrosion resistance, it can produce extremely strong corrosion resistance to the magnesium alloy. Protective effect; at the same time, using the better bonding ability of the siloxane coating, it is used as an intermediate layer to play the role of bonding and bonding, so that the polysiloxane modified fluorocarbon coating can be tightly covered on the magnesium alloy substrate , effectively improving the bonding force between the coating and the substrate, and significantly improving the corrosion resistance of the magnesium alloy.

Description

Anti-corrosion coating on magnesium alloy surface

technical field

The utility model relates to the anticorrosion treatment technology of the magnesium alloy surface, in particular to an anticorrosion coating capable of increasing the binding force between the magnesium alloy surface and organic materials.

Background technique

Magnesium alloy is a light engineering structure metal material with low density, high specific strength, good electrical conductivity and electromagnetic shielding performance, and also has the characteristics of good vibration reduction and damping performance, and easy recycling. Magnesium alloys can be widely used in automotive, aerospace and other fields. However, since the electrode potential of magnesium is very low (-2.37V), its chemical properties are active, and its corrosion resistance is poor, it is usually necessary to add a protective coating on its surface during use.

At present, various organic coatings, such as epoxy, acrylic acid, polyvinyl acid, and fluorocarbon coatings, have been widely used in the surface treatment of metals. Among them, fluorocarbon coatings have been widely used in bridges, steel structures, buildings, etc. due to their good stability, excellent outdoor durability and corrosion resistance. However, it is precisely because of the good stability of the molecular structure of fluorocarbon coatings that it is difficult to combine fluorocarbon coatings with other materials. Therefore, when using fluorocarbon coatings as protective coatings for metal substrates, only surface modification Sexual treatment to improve the bonding force with the metal matrix.

Among the current metal surface pretreatment technologies, the chromate conversion technology developed by Dow Chemical Company in the United States is the most representative, but the treatment solution used in it contains hexavalent chromium ions, which will cause serious damage to the environment and human health. great harm. Therefore, people need to develop environmentally friendly surface pretreatment technology. At present, siloxane pretreatment technology has been applied to steel, aluminum alloy or other metal materials because it can strengthen the combination of metal and organic coating. Therefore, in order to improve the corrosion resistance of magnesium alloys, it is a new direction to study the combination of silane pretreatment technology and fluorocarbon coating.

Utility model content

In view of the above-mentioned deficiencies in the prior art, the purpose of this utility model is to solve the problem that the protective coating on the surface of the current magnesium alloy is difficult to be tightly bonded, so that the protective coating on the surface is easy to flang and fall off during use, and the magnesium alloy is easy to The problem of being corroded, and provide an anti-corrosion coating on the surface of the magnesium alloy that has a strong bonding force with the magnesium alloy, can enhance the corrosion resistance of the magnesium alloy, and has a lower cost.

The technical scheme of the utility model: a magnesium alloy surface anti-corrosion coating, including a magnesium alloy substrate, is characterized in that a polysiloxane modified fluorocarbon coating is arranged on the outer surface of the magnesium alloy substrate, and the magnesium alloy substrate and the A siloxane coating is arranged between the polysiloxane modified fluorocarbon coatings.

Due to the excellent durability and corrosion resistance of the polysiloxane modified fluorocarbon coating, it can have a strong protective effect on magnesium alloys; at the same time, by utilizing the good bonding ability of the silicone coating and metal, the As an intermediate layer, it plays the role of adhesive bonding, which overcomes the problem that the polysiloxane modified fluorocarbon coating itself is too stable so that the bonding force is weak, so that the polysiloxane modified fluorocarbon coating can It is closely covered on the magnesium alloy substrate, giving full play to the durability of the fluorocarbon coating.

Further, the siloxane coating includes a siloxane primer layer and a siloxane transition layer, and the siloxane primer layer is arranged between the magnesium alloy substrate and the siloxane transition layer. Both the base layer and the transition layer are siloxane of the same material. The base layer acts as a pretreatment for the magnesium alloy, and then the transition layer is applied, which not only enhances its bonding ability, but also has a certain protective effect on the magnesium alloy matrix. .

When setting the fluorocarbon coating, the polysiloxane modified fluorocarbon coating is two or more layers, and the polysiloxane modified fluorocarbon coating is set on the magnesium alloy substrate by brushing or spraying The outermost layer to make it more uniform and prevent partial shedding.

The utility model solves the problem of weak bonding force between the fluorocarbon coating and the magnesium alloy substrate, and effectively improves the bonding force between the coating and the substrate through siloxane pretreatment and siloxane modification of the fluorocarbon coating, and significantly Improve the corrosion resistance of magnesium alloys.

Compared with the prior art, the utility model has the following advantages:

1. Two layers of siloxane coating are set on the surface of magnesium alloy to form the base layer and transition layer of siloxane. After two siloxane pretreatments, the polysiloxane modified fluorocarbon coating can be effectively improved. The combination of organic coatings such as layers and metal materials further enhances the corrosion resistance of the magnesium alloy substrate;

2. Since the polysiloxane-modified fluorocarbon coating has excellent weather resistance, the corrosion resistance of the substrate is significantly enhanced by spraying the siloxane-modified fluorocarbon coating on the outer surface of the alloy;

3. The construction process of the anti-corrosion coating of this structure is simple, the production efficiency is high, and the production cost is low, the technology is safe and environmentally friendly, and it is suitable for large-scale production and popularization and application.

Description of drawings

Fig. 1 is a distribution structure diagram of the anti-corrosion coating of the present invention.

In the figure, 1-magnesium alloy substrate, 2-priming layer, 3-transition layer, 4-polysiloxane modified fluorocarbon coating.

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment, the utility model is further described.

Embodiment 1: A kind of anticorrosion coating on the surface of magnesium alloy, comprises magnesium alloy substrate 1, polysiloxane modified fluorocarbon coating 4 is set on the outer surface of magnesium alloy substrate 1, in magnesium alloy substrate 1 and polysiloxane A siloxane coating is arranged between the alkane-modified fluorocarbon coatings 4 .

The siloxane coating is used to increase the bonding force between the polysiloxane modified fluorocarbon coating 4 and the magnesium alloy substrate 1, and it also has a certain anti-corrosion ability, which further enhances the protection of the magnesium alloy Effect.

The utility model adopts the surface treatment of the extruded plate AZ31 magnesium alloy, and the obtained coating structure sample is tested by the electrochemical experiment, which can effectively improve the corrosion resistance of the base material, and the corrosion current density is lower than that of the base material. Nearly 4 orders of magnitude.

Embodiment 2: as shown in Figure 1, a kind of magnesium alloy surface anticorrosion coating is arranged on the magnesium alloy substrate 1, and polysiloxane modified fluorocarbon coating 4 is set on the outer surface of magnesium alloy substrate 1, on Two layers of siloxane coatings are arranged between the magnesium alloy substrate 1 and the polysiloxane modified fluorocarbon coating 4, and the siloxane coatings are a siloxane primer layer 2 and a siloxane transition layer 3, The siloxane primer layer 2 is arranged between the magnesium alloy substrate 1 and the siloxane transition layer 3 .

The siloxane primer layer 2 acts as a pretreatment for the magnesium alloy substrate, forming a thin layer with strong bonding force on the surface of the magnesium alloy substrate; the siloxane transition layer 3 is used to combine with polysiloxane modified fluorocarbon Coating 4 combined, while also increasing the thickness of the silicone coating.

Embodiment 3: a kind of anticorrosion coating on the surface of magnesium alloy, is arranged on the magnesium alloy substrate 1, is provided with two or more polysiloxane modified fluorocarbon coatings 4 on the outer surface of the magnesium alloy substrate 1, in A siloxane coating is arranged between the magnesium alloy substrate 1 and the polysiloxane modified fluorocarbon coating 4 .

In the above embodiments, the polysiloxane modified fluorocarbon coating 4 is set on the magnesium alloy substrate by brushing or spraying. The main purpose of brushing or spraying is to form a protective coating with layered structure as described above on the surface of the magnesium alloy substrate. This protective coating has the characteristics of corrosion resistance, dense fastening and uniform distribution, and can protect the magnesium alloy substrate. Form long-term effective protection.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model rather than limit the technical solutions. Although the applicant has described the utility model in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that, Those who make modifications or equivalent replacements to the technical solutions of the present invention without departing from the purpose and scope of the technical solutions shall be included in the scope of the claims of the present invention.

Claims (3)

1. a magnesium alloy surface anticorrosion coating, comprising a magnesium alloy substrate (1), is characterized in that a polysiloxane modified fluorocarbon coating (4) is set on the outer surface of the magnesium alloy substrate (1), A siloxane coating is arranged between the magnesium alloy substrate (1) and the polysiloxane modified fluorocarbon coating (4). 2. magnesium alloy surface anticorrosion coating according to claim 1, is characterized in that, described siloxane coating comprises siloxane priming layer (2) and siloxane transition layer (3), siloxane The primer layer (2) is arranged between the magnesium alloy substrate (1) and the siloxane transition layer (3). 3. The anticorrosion coating on the surface of magnesium alloy according to claim 1, characterized in that, the polysiloxane modified fluorocarbon coating (4) is two or more.

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