A method for bonding the interface between a plastic liner and a metal bottle valve seat

Abstract

The present invention belongs to the technical field of manufacturing hydrogen storage cylinders, and specifically relates to a method for bonding the interface of a plastic liner and a metal bottle valve seat, comprising the following steps: preparing a groove on the surface of the metal bottle valve seat, and distributing feed holes on the bottom edge of the metal bottle valve seat; preparing micron-sized pits on the surface of the metal bottle valve seat for setting the plastic liner; treating the area where the micron-sized pits are located so that the micron-sized pits form a microporous structure; using a specific solution to pretreat the surface of the metal bottle valve seat, and in the process of rotational integral molding of the plastic liner, the plastic melt reacts with the attached solution to generate heat, and the plastic melt is evenly filled in the microporous structure on the surface of the metal bottle valve seat, completing the integral molding of the metal bottle valve seat and the plastic liner. The present invention proposes a method for firmly bonding the plastic liner to the metal bottle valve seat, thereby improving the bonding strength, sealing and durability of the plastic liner and the metal bottle valve seat.

Description

Technical Field

[0001] The invention belongs to the technical field of hydrogen storage cylinder manufacturing, and specifically relates to a method for bonding an interface between a plastic liner and a metal cylinder valve seat. Background Art

[0002] Type IV hydrogen storage cylinders have the advantages of high hydrogen storage density, good fatigue performance, high manufacturing efficiency and low cost. They have been mass-produced and applied in Japan, the United States, France and other countries. Major domestic manufacturers are accelerating the development of Type IV hydrogen storage cylinders.

[0003] Type IV hydrogen storage cylinders are continuously filled and released during use, which places high demands on the fatigue performance of the cylinders. The junction between the plastic liner and the metal cylinder valve seat is the weakest part of the cylinder. Under the action of periodic dynamic loads, the probability of damage is multiplied compared to other areas, so this area is also a high-risk area for hydrogen leakage.

[0004] At present, most gas cylinder manufacturers use metal and plastic bonding technology or one-piece molding technology. The bonding process has high requirements on the performance of adhesives. Adhesives are seriously affected by environmental performance and will greatly increase the risk of failure under dynamic loads, causing cracks in the metal bottle valve seat and plastic liner, thereby causing gas cylinder leakage or explosion. Compared with the bonding process, the one-piece molding process has the advantages of high bonding strength, strong reliability, and good sealing performance. However, the bonding force of this process mainly comes from the molecular force between metal and plastic. At the same time, the bonding area between the metal bottle valve seat and the plastic liner may also produce defects such as bubbles due to design, material and process limitations, thereby reducing the bonding ability of the metal bottle valve seat and the plastic liner. Summary of the invention

[0005] In order to solve the problems of insufficient bonding strength and easy failure under high pressure and periodic dynamic load faced in the existing plastic liner and metal bottle valve seat molding process, the present invention provides a plastic liner and metal bottle valve seat interface bonding method.

[0006] The object of the present invention is to achieve the following technical solution. According to the present invention, a method for bonding the interface between a plastic liner and a metal bottle valve seat comprises the following steps:

[0007] A groove is prepared on the surface of the metal bottle valve seat for setting the plastic liner, and two or more feed holes are distributed on the bottom edge of the metal bottle valve seat;

[0008] Micron-sized pits are prepared on the surface of the metal bottle valve seat for setting the plastic liner by chemical etching;

[0009] The area where the micron-sized pits are located is processed by a chemical deposition process, so that the micron-sized pits form a microporous structure;

[0010] The surface of the metal bottle valve seat is pretreated with a specific solution, and the specific solution adheres to the surface of the metal bottle valve seat;

[0011] During the rotational molding process of the plastic liner, the plastic melt reacts with the attachment solution to generate heat, the flow rate of the plastic melt is increased, and the plastic melt is evenly filled in the microporous structure on the surface of the metal bottle valve seat, completing the integral molding of the metal bottle valve seat and the plastic liner.

[0012] Furthermore, the metal bottle valve seat is made of 6061 aluminum alloy, the groove is a dovetail groove, and the roughness Ra of the inner wall of the dovetail groove is controlled to be 12.5 after processing.

[0013] Furthermore, the dovetail grooves extend in the circumferential direction of the metal bottle valve seat, and the dovetail grooves located on the same circumference form a dovetail groove group, and each dovetail groove group includes a plurality of dovetail grooves located on the same circumference and distributed circumferentially.

[0014] Furthermore, one or more dovetail groove groups are axially arranged on the inner side wall of the metal bottle valve seat.

[0015] Furthermore, the bottom wall of the metal bottle valve seat is provided with a dovetail groove group or a plurality of dovetail groove groups distributed concentrically around the axis of the metal bottle valve seat.

[0016] Furthermore, the opening and bottom corners of the dovetail groove are both rounded.

[0017] Furthermore, when chemically corroding the metal bottle valve seat, first, the metal bottle valve seat is cleaned with ultrasound in anhydrous ethanol to remove stains on the surface of the bottle valve seat; after cleaning and drying, it is treated with an oil bath, and the oil temperature is controlled at room temperature; the part of the metal bottle valve seat that needs to be treated with micropores is immersed in a sodium hydroxide solution of a specific concentration, and after the aluminum oxide film on the surface of the metal bottle valve seat is completely corroded, the metal bottle valve seat is immersed in a hydrochloric acid solution of a specific concentration; after being corroded by the sodium hydroxide solution and the hydrochloric acid solution, micron-sized pits will appear on the surface of the metal bottle valve seat.

[0018] Furthermore, the chemical deposition method uses plasma chemical deposition, specifically: using radio frequency plasma discharge equipment, radio frequency plasma generates active groups under the discharge equipment, and metal oxides are quickly generated on the aluminum surface in the area where the micron-sized pits are located; by controlling the discharge voltage and frequency of the discharge equipment and the flow rate of the gas, the position and size of the metal oxide deposition in the micron-sized pits of the metal bottle valve seat are controlled, so that the micron-sized metal oxide film deposited on the side wall of the micron-sized pit is accumulated, the opening area is reduced, and a microporous structure is prepared.

[0019] Furthermore, the surface of the metal bottle valve seat is chemically pretreated with an amine aqueous solution, and the nitrogen element in the amine aqueous solution forms a coordination bond on the surface of the metal bottle valve seat, and the amine groups of the amine aqueous solution adhere to the surface of the metal bottle valve seat.

[0020] Compared with the prior art, the present invention is beneficial in that:

[0021] First, a segmented groove is set on the inner wall of the metal bottle valve seat to prevent the metal bottle valve seat from slipping due to the circumferential load, which causes the metal bottle valve seat and the plastic liner to rotate relative to each other, and at the same time, it can prevent the metal bottle valve seat from escaping from the plastic liner due to impact loads on the gas cylinder; an circumferential groove is designed in the bottom area of ​​the metal bottle valve seat, and a plurality of feed holes are evenly distributed in the circumferential direction to increase the feed amount and feed rate of the groove in this area, thereby ensuring the density of the nylon material in this area, thereby enhancing the bonding ability of the metal bottle valve seat and the plastic liner.

[0022] Second, the microporous structure on the surface of the metal bottle valve seat can increase the mechanical interlocking between the plastic material and the metal material, increase the contact area between the metal bottle valve seat and the plastic liner, and thus enhance the interaction force between the metal bottle valve seat and the plastic liner.

[0023] Third, the surface of the metal bottle valve seat is treated with a specific solution to increase the flow rate of the plastic melt, so that the plastic melt can be more easily filled in the microporous structure during the rotational molding process, thereby achieving direct bonding between the metal material and the plastic.

[0024] The present invention proposes a method for firmly bonding a plastic liner to a metal bottle valve seat, thereby solving the problems of insufficient bonding strength and easy failure under high pressure and periodic dynamic load faced in the existing plastic liner and metal bottle valve seat molding process, and improving the bonding strength, sealing and durability of the plastic liner and the metal bottle valve seat.

[0025] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following specifically cites a preferred embodiment and describes it in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the combination of a nylon plastic liner and a metal bottle valve seat in an embodiment of a method for combining a plastic liner and a metal bottle valve seat interface of the present invention;

[0027] Figure 2 for Figure 1 Enlarged cross-sectional view of the dovetail groove on the inner wall of the valve seat of the middle metal bottle

[0028] Figure 3 for Figure 1 Schematic diagram of radial cross section of the area where the segmented dovetail groove on the inner wall of the middle metal bottle valve seat is located;

[0029] Figure 4 for Figure 1 Schematic diagram of the structure of micron-scale pits on the surface of the valve seat of the middle metal bottle;

[0030] Figure 5 for Figure 4 Schematic diagram of the structure after chemical deposition of medium-micrometer-sized pits.

[0031] [Reference Signs]

[0032] 1- nylon plastic lining, 2- metal bottle valve seat, 3- dovetail groove, 4- micron-level pits, 5- feed hole, 6- microporous structure. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] An embodiment of a method for bonding a plastic liner to a metal bottle valve seat interface of the present invention comprises the following steps:

[0035] 1) A circumferentially extending groove is prepared on the inner side wall and the bottom surface of the metal bottle valve seat 2 by machining or the like, and two or more feed holes are distributed on the bottom edge of the metal bottle valve seat 2.

[0036] The steps are as follows:

[0037] According to the recommendation of GB / T42612 "Car Compressed Hydrogen Plastic Liner Carbon Fiber Fully Wrapped Gas Cylinder", the metal bottle valve seat 2 is made of 6061 aluminum alloy, and the overall structure of the metal bottle valve seat 2 is a rotating body. Figure 1 The figure shows the partial structure of the cross section of the rotating body. In this embodiment, the groove adopts a dovetail groove 3, such as Figure 2 As shown, the roughness Ra of the inner wall of the dovetail groove 3 is controlled at about 12.5.

[0038] The metal bottle valve seat 2 is prone to "hydrogen embrittlement" when in contact with high-pressure hydrogen, which leads to a decrease in the mechanical properties of the metal bottle valve seat 2 and stress corrosion cracking. In order to prevent the bottom of the metal bottle valve seat 2 from being in contact with hydrogen for a long time, and thus prevent the high-pressure hydrogen from directly contacting the metal bottle valve seat 2 to produce the "hydrogen embrittlement" effect, the bottom and sides of the metal bottle valve seat structure are completely wrapped with a nylon plastic liner, which can also enhance the sealing performance of the gas cylinder. In order to enhance the bonding ability of nylon plastic and the metal bottle valve seat, a dovetail groove 3 is provided at the bottom and inner wall of the metal bottle valve seat.

[0039] The dovetail groove 3 extends in the circumferential direction of the metal bottle valve seat 2. The dovetail grooves 3 located on the same circumference are a dovetail groove group. Each dovetail groove group includes multiple dovetail grooves 3 located on the same circumference and distributed circumferentially. In the present embodiment, the same dovetail groove group includes three sections of dovetail grooves 3 evenly distributed.

[0040] like Figure 3 The figure shows a radial cross-section of the dovetail groove on the inner wall of the metal bottle valve seat 2. One or more dovetail groove groups can be set in the axial direction of the inner wall of the metal bottle valve seat 2. After the plastic melt fills the above-mentioned dovetail grooves 3, the intervals between the dovetail grooves 3 in the same circumferential direction can effectively prevent the nylon plastic liner 1 formed by the plastic melt from slipping due to the circumferential load on the metal bottle valve seat during the repeated filling and discharging of hydrogen in the gas cylinder. The segmented "dovetail groove" structure designed on the inner wall of the metal bottle valve seat 2 can prevent the plastic material from escaping from the hole of the metal bottle valve seat 2, and can effectively prevent the metal bottle valve seat 2 from circumferentially slipping on the interface due to the circumferential load.

[0041] In order to further enhance the bonding ability between the metal bottle valve seat 2 and the nylon plastic liner 1, a dovetail groove 3 extending circumferentially is provided in the bottom area of ​​the metal bottle valve seat 2, and a dovetail groove group or a plurality of dovetail groove groups distributed concentrically are provided on the bottom wall of the metal bottle valve seat 2 around the axis of the metal bottle valve seat 2. In this embodiment, the metal bottle valve seat 2 is provided with the nylon plastic liner 1 by means of rotational molding. Considering that the nylon material in the area where the bottom groove is located cannot be completely filled during the rotational molding process, thereby generating defects such as bubbles, two or more feed holes 5 are evenly distributed in the circumferential direction of the bottom edge of the metal bottle valve seat 2. In this embodiment, four feed holes 5 are provided to increase the feed amount and feed rate of the groove in this area, ensure the density of the nylon material in this area, and thus enhance the bonding ability between the metal bottle valve seat and the plastic liner.

[0042] The enlarged cross section of the segmented dovetail groove structure is as follows: Figure 2 As shown, the corners (opening and bottom corners) of the dovetail groove 3 are rounded to prevent the plastic melt from being evenly filled into the dovetail groove 3, and to reduce stress concentration to a certain extent.

[0043] 2) Micron-sized pits 4 are prepared on the surface of the metal bottle valve seat 2 for setting the plastic liner by chemical etching.

[0044] The steps are as follows:

[0045] First, the metal bottle valve seat 2 is cleaned with ultrasound in anhydrous ethanol to remove stains on the surface of the bottle valve seat; after cleaning and drying, it is treated with an oil bath, and the oil temperature is controlled at room temperature; the part of the metal bottle valve seat 2 that needs to be treated with micropores is immersed in a sodium hydroxide solution of a specific concentration, and after the aluminum oxide film on the surface of the metal bottle valve seat 2 is completely corroded, the metal bottle valve seat 2 is immersed in a hydrochloric acid solution of a specific concentration. After being corroded by the sodium hydroxide solution and the hydrochloric acid solution, micron-sized pits 4 will appear on the surface of the metal bottle valve seat 2. The structure of the micron-sized pits 4 is as shown in FIG. Figure 4 shown.

[0046] 3) The area where the micron-sized pits 4 are located is processed by a plasma chemical deposition process, so that the micron-sized pits 4 form a microporous structure 6 with a reduced opening of the micron-sized pits 4 .

[0047] The steps are as follows:

[0048] Radio frequency plasma discharge equipment is used. Radio frequency plasma can generate active groups under the discharge equipment. The active groups have strong oxidizing properties and can quickly generate metal oxides on the aluminum surface in the area where the micron-sized pits 4 are located. By controlling the discharge voltage and frequency of the discharge equipment and the flow rate of the gas, the position and size of the metal oxide deposition in the micron-sized pits of the metal bottle valve seat can be accurately controlled. This process can quickly generate metal oxides on the metal surface, and the micron-sized metal oxide film deposited on the side wall of the pit is accumulated, such as Figure 5 As shown, the opening area is reduced and a microporous structure 6 is prepared, thereby increasing the contact area between the plastic melt and the metal bottle valve seat 2.

[0049] Micron-sized pits 4 are prepared on the metal surface by chemical etching, and metal oxides are deposited on the sidewalls of the pits by chemical deposition to reduce the opening area, thereby preparing a microporous structure 6. By preparing the microporous structure 6 on the surface of the metal bottle valve seat 2, the mechanical interlocking generated by the nylon plastic melt flowing into the microporous structure 6 on the surface of the metal bottle valve seat 2 is strengthened, the contact area between the metal bottle valve seat 2 and the nylon plastic liner 1 is increased, and the bonding force between the metal bottle valve seat 2 and the nylon plastic liner 1 is enhanced.

[0050] 4) The surface of the metal bottle valve seat 2 is chemically pretreated with a specific solution (such as an amine aqueous solution), the nitrogen element in the amine aqueous solution forms a coordination bond on the surface of the metal bottle valve seat 2, and the amine groups of the amine aqueous solution are attached to the surface of the metal bottle valve seat 2.

[0051] 5) During the rotational molding process of the nylon plastic liner 1, the heat generated by the reaction between the plastic melt and the amine groups in the amine aqueous solution can increase the kinetic energy of the plastic melt and improve the flow rate of the plastic melt, thereby allowing the plastic melt to more fully and evenly fill the microporous structure 6 on the metal surface, ultimately completing the integral molding of the metal bottle valve seat 2 and the nylon plastic liner 1.

[0052] The surface of the metal bottle valve seat 2 is pretreated with a specific solution, and the specific elements in the solution can form coordination bonds on the metal surface and make the solution adhere to the metal bottle valve seat 2; during the rotational molding of the nylon plastic liner, the heat generated by the reaction between the plastic melt and the attached specific solution can increase the flow rate of the plastic melt, thereby making the plastic melt more fully dispersed in the microporous structure 6 on the metal surface, thereby enhancing the bonding ability of the nylon plastic liner 1 and the metal bottle valve seat 2.

[0053] The present invention can effectively prevent the nylon plastic liner 1 and the metal bottle valve seat 2 from being separated due to insufficient bonding strength by establishing a "dovetail groove" structure on the surface of the metal bottle valve seat 2. At the same time, the segmented "dovetail groove" design can also bear part of the circumferential load and limit the relative rotation of the metal bottle valve seat 2 and the nylon plastic liner 1; the evenly distributed feed holes 5 can increase the filling amount and filling rate of the raw material of the lining in the bottom dovetail groove area, can reduce the generation of defects such as bubbles, and increase the density of the material in the dovetail groove area. The present invention can effectively strengthen the mechanical interlocking generated by the plastic flowing into the metal surface microporous structure 6 by arranging a microporous structure 6 on the metal material surface of the metal bottle valve seat 2, increase the contact area between the metal bottle valve seat 2 and the nylon plastic liner 1, and thus enhance the bonding force between the nylon plastic liner 1 and the metal bottle valve seat 2. The present invention uses a specific solution to pretreat the surface of the metal bottle valve seat 2. The heat generated by the reaction between the nylon plastic melt and the solution during rotational molding can increase the flow rate and filling effect of the plastic melt, thereby enhancing the bonding force between the nylon plastic liner 1 and the metal bottle valve seat 2.

[0054] The metal bottle valve seat 2 is processed by processing a "dovetail groove" structure and evenly distributed feed holes on the surface of the metal bottle valve seat 2, arranging a microporous structure on the surface of the metal bottle valve seat, and performing surface pretreatment on the metal. The metal bottle valve seat 2 is processed by the above structural design and process method. In the one-piece molding process of the nylon plastic liner 1 and the metal bottle valve seat 2, the bonding force between the plastic liner 1 and the valve seat 2 can be significantly improved, thereby solving the problem of insufficient interface bonding strength and easy failure of the nylon plastic liner 1 and the metal bottle valve seat 2 under high pressure and periodic dynamic loads.

[0055] Through the interface bonding method of the nylon plastic liner 1 and the metal bottle valve seat 2 of the present invention, the bonding force between the nylon plastic liner 1 and the metal bottle valve seat 2 can be effectively strengthened, the risk of hydrogen leakage at the joint can be avoided, the sealing performance can be enhanced, the product quality of the hydrogen storage bottle can be improved, and safety hazards can be reduced.

[0056] Compared with the prior art, the beneficial effects of the present invention are summarized as follows:

[0057] First, a segmented "dovetail groove" structure and other grooves are designed to prevent the metal bottle valve seat 2 from slipping due to annular loads, causing relative rotation between the metal bottle valve seat 2 and the plastic liner, and at the same time prevent the metal bottle valve seat from escaping from the plastic liner due to impact loads and the like. An annular groove is designed in the bottom area of ​​the metal bottle valve seat 2, and 4 feed holes are evenly distributed in the circumferential direction to increase the feed amount and feed rate of the groove in this area, thereby ensuring the density of the nylon material in this area, thereby enhancing the bonding ability between the metal bottle valve seat and the plastic liner.

[0058] Second, the microporous structure on the surface of the metal bottle valve seat can enhance the mechanical interlocking between the plastic material and the metal material, increase the contact area between the metal bottle valve seat and the plastic liner, and thus enhance the interaction force between the bottle valve seat and the plastic liner.

[0059] Third, the metal surface is treated with a specific solution to increase the flow rate of the plastic melt, so that the plastic melt can be more easily filled in the microporous structure during the rotational molding process, thereby achieving direct bonding between the metal material and the plastic.

[0060] In other embodiments, the dovetail groove may also be replaced by grooves of other shapes, such as a U-shaped groove, a straight groove with a small opening and a large interior, etc.

[0061] In other embodiments, nylon plastic may be provided on the metal bottle valve seat 2 by injection molding or the like.

[0062] In other embodiments, the nylon plastic may also be replaced by other types of plastic as the plastic lining of the metal bottle valve seat 2 .

[0063] In other embodiments, the metal bottle valve seat 2 may be placed in only one of a sodium hydroxide solution and a hydrochloric acid solution for corrosion treatment.

[0064] In other embodiments, other chemical deposition methods or other plasma discharge equipment may be used.

[0065] In other embodiments, the amine aqueous solution may be replaced by other solutions, as long as the solution can adhere to the surface of the metal bottle valve seat 2 and can react with the plastic melt to generate heat.

[0066] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for bonding the interface between a plastic liner and a metal bottle valve seat, characterized in that: The following steps are involved: A groove is prepared on the surface of the metal bottle valve seat for setting the plastic liner, and two or more feed holes are distributed on the bottom edge of the metal bottle valve seat; Micron-sized pits are prepared on the surface of the metal bottle valve seat for setting the plastic liner by chemical etching; The area where the micron-sized pits are located is processed by a chemical deposition process, so that the micron-sized pits form a microporous structure; The surface of the metal bottle valve seat is pretreated with a specific solution, and the specific solution adheres to the surface of the metal bottle valve seat; During the rotational molding process of the plastic liner, the plastic melt reacts with the attachment solution to generate heat, the flow rate of the plastic melt is increased, and the plastic melt is evenly filled in the microporous structure on the surface of the metal bottle valve seat, completing the integral molding of the metal bottle valve seat and the plastic liner.

2. A method for bonding the interface between a plastic liner and a metal bottle valve seat according to claim 1, characterized in that: The metal bottle valve seat is made of 6061 aluminum alloy, and the groove is a dovetail groove. After processing, the roughness Ra of the inner wall of the dovetail groove is controlled at 12.

5.

3. A method for bonding the interface between a plastic liner and a metal bottle valve seat according to claim 2, characterized in that: The dovetail grooves extend in the circumferential direction of the metal bottle valve seat, and the dovetail grooves located on the same circumference form a dovetail groove group, and each dovetail groove group includes a plurality of dovetail grooves located on the same circumference and distributed circumferentially.

4. A method for bonding the interface between a plastic liner and a metal bottle valve seat according to claim 3, characterized in that: One or more dovetail groove groups are axially arranged on the inner side wall of the metal bottle valve seat.

5. The method for bonding the interface between a plastic liner and a metal bottle valve seat according to claim 3, characterized in that: The bottom wall of the metal bottle valve seat is provided with a dovetail groove group or a plurality of dovetail groove groups distributed concentrically around the axis of the metal bottle valve seat.

6. A method for bonding a plastic liner to a metal bottle valve seat interface according to claim 2, characterized in that: The opening and bottom corners of the dovetail groove are both rounded.

7. The method for bonding the interface between a plastic liner and a metal bottle valve seat according to claim 1, characterized in that: When chemically corroding the metal bottle valve seat, first, clean the metal bottle valve seat with ultrasound in anhydrous ethanol to remove stains on the surface of the bottle valve seat; after cleaning and drying, perform oil bath treatment, and control the oil temperature at room temperature; immerse the part of the metal bottle valve seat that needs micropore treatment in a sodium hydroxide solution of a specific concentration, and after the aluminum oxide film on the surface of the metal bottle valve seat is completely corroded, immerse the metal bottle valve seat in a hydrochloric acid solution of a specific concentration; After being corroded by sodium hydroxide solution and hydrochloric acid solution, micron-sized pits will appear on the surface of the metal bottle valve seat.

8. The method for bonding the interface between a plastic liner and a metal bottle valve seat according to claim 1, characterized in that: Plasma chemical deposition is selected as the chemical deposition method, specifically: using radio frequency plasma discharge equipment, radio frequency plasma generates active groups under the discharge equipment, and metal oxides are quickly generated on the aluminum surface in the area where the micron-sized pits are located; by controlling the discharge voltage and frequency of the discharge equipment and the flow rate of the gas, the position and size of the metal oxide deposition in the micron-sized pits of the metal bottle valve seat are controlled, so that the micron-sized metal oxide film deposited on the side wall of the micron-sized pit is accumulated, the opening area is reduced, and a microporous structure is prepared.

9. The method for bonding the interface between a plastic liner and a metal bottle valve seat according to claim 1, characterized in that: The surface of the metal bottle valve seat is chemically pretreated with an amine aqueous solution, and the nitrogen element in the amine aqueous solution forms a coordination bond on the surface of the metal bottle valve seat, and the amine groups of the amine aqueous solution are attached to the surface of the metal bottle valve seat.

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