Anti-hydrogen embrittlement hydrogen sprayer of hydrogen internal combustion engine

Abstract

The utility model relates to a hydrogen embrittlement resistant hydrogen sprayer of a hydrogen internal combustion engine, which comprises a valve body and a sprayer component sleeved on the outer surface of one end of the valve body. A first coating is arranged on the surface of the nozzle component, and a second coating is arranged on the surface of the valve body; the first coating is thicker than the second coating. Compared with the prior art, according to different working conditions of the nozzle component and the valve body, coatings with different thicknesses are arranged on the nozzle component and the valve body, the actual use condition is met, and the service life of the hydrogen sprayer is guaranteed; and only the surface, in contact with hydrogen, of the valve body is provided with the coating, so that the production cost is effectively reduced.

Description

Technical Field

[0001] This utility model relates to hydrogen internal combustion engines, and more particularly to a hydrogen injector for hydrogen internal combustion engines that is resistant to hydrogen embrittlement. Background Technology

[0002] A hydrogen internal combustion engine, also known as a hydrogen fuel cell internal combustion engine, retains the main structure and systems of a traditional internal combustion engine. By improving components such as the fuel supply system and injection system, it uses hydrogen as fuel to generate power, thereby driving the vehicle. Its basic principle is the same as that of a regular gasoline or diesel internal combustion engine, employing a classic cylinder-piston structure and converting chemical energy into mechanical energy through four strokes: intake, compression, power, and exhaust. The hydrogen injector is a key component of a hydrogen internal combustion engine, operating under high temperature, high pressure, and a hydrogen-filled environment, especially in direct-injection hydrogen internal combustion engines. Therefore, hydrogen injectors are highly susceptible to hydrogen embrittlement, leading to a reduced lifespan.

[0003] Resistance to hydrogen embrittlement is a crucial safety indicator for hydrogen fuel cell engines. When metallic materials are subjected to external forces, the stress distribution within the material is uneven, leading to stress concentration in areas of rapid transition in the material's shape or at internal defects and microcracks. Under the influence of stress gradients, hydrogen atoms diffuse within the crystal lattice or follow dislocations towards stress concentration areas. Due to the interaction between hydrogen and metal atoms, the bonding force between metal atoms weakens, causing cracks to initiate and propagate in high-hydrogen regions, resulting in brittle fracture. Hydrogen embrittlement is prone to occur in high-temperature, high-pressure environments filled with hydrogen gas. Hydrogen injectors in hydrogen internal combustion engines, especially those in direct-injection hydrogen internal combustion engines, are frequently exposed to this environment, making them highly susceptible to hydrogen embrittlement and reduced lifespan. To prevent hydrogen embrittlement, three main measures are currently employed: first, using hydrogen-resistant materials, such as austenitic stainless steel, aluminum and its alloys, and copper and its alloys, which have low sensitivity to hydrogen embrittlement; second, applying coatings with low hydrogen diffusivity and solubility to the surfaces of components; and third, reducing the solubility of components for hydrogen through heat treatment.

[0004] Application publication number CN118417142A discloses a composite coating method for bolt parts with zinc penetration and Dacromet paint sealing. It adopts a multi-level anti-corrosion technology of "zinc penetration + two Dacromet coatings + high-hardness coating paint sealing", which makes the coating have the advantages of corrosion resistance, high hardness, wear resistance, strong adhesion and uniform coating. However, it does not consider the applicability of the coating to hydrogen injectors under different working conditions.

[0005] Therefore, designing a hydrogen injector with strong resistance to hydrogen embrittlement and suitable for different working conditions is a technical problem that needs to be solved. Utility Model Content

[0006] The purpose of this invention is to overcome the shortcomings of the existing technology, which is not applicable to different working conditions, and to provide a hydrogen embrittlement-resistant hydrogen injector for hydrogen internal combustion engines.

[0007] The objective of this utility model can be achieved through the following technical solutions:

[0008] According to one aspect of the present invention, a hydrogen embrittlement-resistant hydrogen injector for a hydrogen internal combustion engine is provided, comprising a valve body and a nozzle component, wherein the nozzle component is sleeved on the outer surface of one end of the valve body; a first coating is provided on the surface of the nozzle component, and a second coating is provided on the surface of the valve body; the thickness of the first coating is greater than that of the second coating.

[0009] As a preferred technical solution, the surface of the valve body is divided into a first region and a second region, the first region being in contact with hydrogen gas, and the second coating being disposed in the first region.

[0010] As a preferred technical solution, both the first coating and the second coating include multiple sub-coatings, and the number of sub-coatings included in the first coating and the second coating is different.

[0011] As a preferred technical solution, the thickness of the sub-coating is 3 to 10 μm.

[0012] As a preferred technical solution, the sub-coating has N layers, where N is a positive integer and N≥2, and the N sub-coating layers are stacked sequentially; wherein, the sub-coating layer closer to the valve body or nozzle component is the first sub-coating layer, and the sub-coating layer farther away from the valve body or nozzle component is the Nth sub-coating layer; the thickness of the first sub-coating layer is 3 to 5 μm, and the thickness of the second sub-coating layer is 6 to 10 μm.

[0013] As a preferred technical solution, the first coating has a thickness of 50 μm and includes three or four stacked sub-coatings.

[0014] As a preferred technical solution, the second coating has a thickness of 10 μm and includes two stacked sub-coating layers.

[0015] As a preferred technical solution, the first coating and / or the second coating include zinc, aluminum and chromium.

[0016] As a preferred technical solution, in the first coating and / or the second coating, the zinc content is less than or equal to 70%, the aluminum content is less than or equal to 30%, and the chromium content is less than or equal to 15%.

[0017] As a preferred technical solution, the surfaces of the nozzle component with the first coating and the valve body with the second coating are both surfaces that have undergone shot blasting treatment.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1) This utility model sets coatings of different thicknesses on the nozzle components and valve body for different working conditions, which conforms to actual use and ensures the service life of the hydrogen injector; the coating is only set on the surface of the valve body that comes into contact with hydrogen, which can effectively reduce production costs.

[0020] 2) The thickness of the sub-coating of this utility model is 3 to 10 μm. Compared with electro-galvanizing, hot-dip galvanizing or other coating methods, it is thinner and does not affect the performance of the parts without changing the corrosion resistance, heat resistance and hydrogen embrittlement resistance.

[0021] 3) This utility model uses a coating made of zinc, aluminum and chromium, which eliminates the need for precious metals such as gold and silver while ensuring corrosion resistance, thus greatly reducing costs; shot blasting is performed on the surface of the hydrogen injector with the coating to form a certain roughness so that the coating can adhere, and it can also improve the fatigue life of the hydrogen injector and further prevent brittle fracture. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of an anti-hydrogen embrittlement hydrogen injector for a hydrogen internal combustion engine according to the present invention.

[0023] Figure 2 This is a schematic diagram of the first coating structure of this utility model;

[0024] Figure 3 This is a schematic diagram of the second coating structure of this utility model;

[0025] The numbers in the diagram are as follows:

[0026] 1. Valve body; 11. First coating; 2. Nozzle assembly; 21. Second coating. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of the present utility model. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present utility model.

[0028] like Figure 1As shown, this embodiment provides a hydrogen injector for a hydrogen internal combustion engine that resists hydrogen embrittlement, including a valve body 1 and a nozzle component 2. The nozzle component 2 is sleeved on the outer surface of one end of the valve body 1. A first coating 11 is provided on the surface of the nozzle component 2, and a second coating 21 is provided on the surface of the valve body 1. When the hydrogen internal combustion engine is operating in a direct injection manner, the nozzle component 2 typically operates in a relatively harsh environment. Therefore, to ensure the service life of the internal combustion engine, applying different coatings to the nozzle component 2 can ensure that it still has good resistance to hydrogen embrittlement under high temperature and high pressure, thereby guaranteeing the service life of the hydrogen injector.

[0029] like Figure 2 As shown, the first coating 11 on the surface of the valve body 1 includes multiple sub-coatings. Generally, only a few layers are needed to meet the requirements. Two sub-coatings can be used: the sub-coating closest to the surface of the valve body 1 is the first sub-coating, with a thickness of 3-5 μm, and the sub-coating furthest from the surface of the valve body 1 is the second sub-coating, with a thickness of 6-10 μm. The overall thickness of the first coating 11 is 10 μm, which is sufficient to ensure durability. The first coating 11 only needs to be applied to surfaces exposed to a hydrogen environment to reduce production costs.

[0030] like Figure 3 As shown, the second coating 21 on the surface of the nozzle component 2 includes multiple sub-coatings. To ensure its service life, a large number of sub-coatings are required, generally 3 to 4 layers. The multiple sub-coatings are stacked sequentially. The sub-coating closest to the valve body 1 or the nozzle component 2 is the first sub-coating, and the sub-coating furthest from the valve body 1 or the nozzle component 2 is the Nth sub-coating. The thickness of the first sub-coating is 3 to 5 μm, and the thickness of the second sub-coating is 6 to 10 μm. The overall thickness of the second coating 21 is 50 μm, ensuring good resistance to hydrogen embrittlement under high temperature and high pressure without affecting the assembly of components. Coatings are required on both the inner and outer surfaces of the nozzle component 2.

[0031] The number of sub-coating layers can be adjusted according to actual work requirements.

[0032] The first coating 11 and the second coating 21 contain zinc, aluminum, and chromium, wherein the zinc content is less than or equal to 70%, the aluminum content is less than or equal to 30%, and the chromium content is less than or equal to 15%. This eliminates the need for precious metals while ensuring corrosion resistance, thus reducing production costs. Specific material ratios can be selected through comparative experiments based on actual needs; appropriate coating composition parameters can be selected for different high-pressure and low-pressure hydrogen injection methods.

[0033] While maintaining the same corrosion resistance, heat resistance, and hydrogen embrittlement resistance, the coating in this embodiment is thinner than that of electroplating, hot-dip galvanizing, or other coatings, and does not affect the performance of the parts.

[0034] To ensure the quality of the coating, the surfaces of the valve body 1 and the nozzle component 2 where the coating is applied need to be cleaned to remove oil and ensure surface cleanliness; shot blasting is also required to create a certain roughness on the surfaces of the valve body 1 and the nozzle component 2, which facilitates coating adhesion.

[0035] This embodiment achieves the goal of reducing production costs and ensuring the service life of the hydrogen injector by using different anti-hydrogen embrittlement coatings on different components of the hydrogen injector.

[0036] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this utility model, and these modifications or substitutions should all be covered within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A hydrogen embrittlement resistant hydrogen sparger for a hydrogen internal combustion engine, characterized by, The valve body (1) and the spray head component (2) are included, the spray head component (2) is sleeved on the outer surface of one end of the valve body (1), the surface of the spray head component (2) is provided with a first coating (11), and the surface of the valve body (1) is provided with a second coating (21); the thickness of the first coating (11) is greater than that of the second coating (21).

2. A hydrogen-embrittling resistant hydrogen sparger for a hydrogen internal combustion engine according to claim 1, characterized by The surface of the valve body (1) is divided into a first region and a second region, the first region is in contact with hydrogen, and the second coating (21) is arranged in the first region.

3. The hydrogen-embrittling hydrogen sparger for a hydrogen internal combustion engine according to claim 1, characterized by The first coating (11) and the second coating (21) each include a plurality of sub-coatings, and the first coating (11) and the second coating (21) include different numbers of sub-coatings.

4. The hydrogen-embrittling hydrogen sparger of claim 3, wherein The thickness of the sub-coating is 3-10 μm.

5. The hydrogen-embrittled hydrogen sparger of claim 3, wherein The sub-coatings are N layers in total, N is a positive integer and N≥2, and the N layers of sub-coatings are sequentially stacked; wherein, the sub-coating close to the valve body (1) or the spray head component (2) is the first sub-coating, and the sub-coating away from the valve body (1) or the spray head component (2) is the Nth sub-coating; the thickness of the first sub-coating is 3-5 μm, and the thickness of the second sub-coating is 6-10 μm.

6. A hydrogen-embrittling hydrogen sparger for a hydrogen internal combustion engine according to claim 3, characterized by The thickness of the first coating (11) is 50 μm, and the first coating (11) includes three or four layers of stacked sub-coatings.

7. The hydrogen sparger of claim 3, wherein the hydrogen sparger is configured to provide a hydrogen pressure of about 1.5 MPa to about 2.5 MPa. The thickness of the second coating (21) is 10 μm, and the second coating (21) includes two layers of stacked sub-coatings.

8. The hydrogen-embrittled hydrogen sparger of claim 1, wherein The first coating (11) and / or the second coating (21) include zinc, aluminum and chromium.

9. A hydrogen-embrittling hydrogen sparger for a hydrogen internal combustion engine according to claim 8, characterized by In the first coating (11) and / or the second coating (21), the content of zinc is less than or equal to 70%, the content of aluminum is less than or equal to 30%, and the content of chromium is less than or equal to 15%.

10. The hydrogen-embrittled hydrogen sparger of claim 1, wherein The surface of the spray head component (2) provided with the first coating (11) and the surface of the valve body (1) provided with the second coating (21) are both surfaces treated by shot blasting.

Images