Metal surface in-situ local corrosion system and use method thereof

Abstract

The invention relates to a metal surface in-situ local corrosion system and a use method thereof. The metal surface in-situ local corrosion system is used for carrying out local corrosion on a metal structure and comprises a corrosion environment bin mounted on a corroded surface of the metal structure; the optical microscope is used for observing the metal structure through the corrosion environment bin; the etchant solution tank is used for providing etchant solution; the peristaltic pump is used for inputting the corrosive liquid in the corrosive liquid tank into the corrosive environment bin; the air pump is used for inputting air into the corrosion environment bin; the corrosion waste liquid pool is used for recycling corrosion liquid; the electromagnetic valve is arranged between the liquid outlet of the corrosion environment bin and the corrosion waste liquid pool; and the control module is used for controlling the optical microscope, the peristaltic pump, the air pump and the electromagnetic valve. Compared with the prior art, a local corrosion environment can be formed on the surface of the tested metal structure, and local corrosion of the metal structure can be observed in situ.

Description

Technical Field

[0001] The invention belongs to the technical field of metal corrosion, and in particular relates to an in-situ local corrosion system for a metal surface and a use method thereof. Background Art

[0002] When conducting research related to defect tolerance of structural parts, it is usually necessary to prefabricate corrosion defects or conduct corrosion tests in some areas of the metal structure. Existing test technologies often require the entire metal structure to be placed in a corrosive environment, which poses a risk of corrosion in non-target areas and cannot achieve local corrosion effects; and the metal structures to be tested are often large in size and complex in shape. Using conventional corrosion methods to corrode the entire sample places high demands on the test equipment and is less economical.

[0003] In addition, since defect tolerance research often requires the examination of the morphology of corrosion defects rather than the corrosion time of traditional corrosion tests, there is a certain demand for in-situ tests that observe corrosion defects in real time. Traditional corrosion methods such as salt spray are prone to corroding observation equipment due to the closed corrosion environment, making it difficult to meet the needs of effective in-situ observation tests.

[0004] Therefore, in response to the technical problems in the above-mentioned defect tolerance related research, it is urgent to develop a local corrosion system that can detect local corrosion and observe the metal surface in situ to meet the needs of prefabricating corrosion defects in partial areas of metal structures or conducting corrosion tests. Summary of the invention

[0005] The purpose of the present invention is to provide a metal surface in-situ local corrosion system and its use method in order to overcome the defects of existing metal corrosion equipment, such as difficulty in local corrosion and inability to effectively observe the corrosion state, so as to meet the relevant research needs of metal defect tolerance.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] The present invention provides a metal surface in-situ local corrosion system, which is used for local corrosion of metal structures, and specifically comprises:

[0008] Corrosion environment chamber installed on the corroded surface of metal structure;

[0009] Optical microscope for observing metal structures through a corrosive environment chamber;

[0010] A corrosion solution tank for providing a corrosion solution;

[0011] A peristaltic pump used to input the corrosive solution in the corrosive solution pool into the corrosive environment chamber;

[0012] An air pump for inputting air into the corrosive environment chamber;

[0013] A corrosion waste liquid pool for recovering corrosion liquid;

[0014] A solenoid valve provided between the liquid outlet of the corrosive environment chamber and the corrosive waste liquid pool;

[0015] Control modules for controlling peristaltic pumps, air pumps and solenoid valves.

[0016] Furthermore, the corrosive environment chamber is installed on the surface of the metal structure using a switchable magnetic seat or a strap.

[0017] Furthermore, the corrosive environment chamber is a box-shaped structure with one side open as a whole.

[0018] Furthermore, a sealing groove is arranged around a surface of the corrosive environment chamber that contacts the metal structure, and a sealing gasket that can be sealed and connected to the sealing groove is arranged on the surface of the metal structure.

[0019] Furthermore, a transparent observation window is provided on a side of the corrosion environment chamber facing the optical microscope.

[0020] Furthermore, the diameter of the observation window is 25-35 mm, and the material of the observation window is quartz glass.

[0021] Furthermore, the optical microscope is composed of a coaxial light source, a microscopic optical path, a telephoto objective lens and a CCD camera.

[0022] Furthermore, the graphic data collected by the CCD camera is transmitted to the control module.

[0023] Furthermore, the liquid outlet of the peristaltic pump and the liquid outlet of the air pump are both provided with a one-way valve to prevent the liquid in the pipeline from flowing back and contaminating the corrosion solution pool or damaging the instrument.

[0024] Furthermore, the two sides of the corrosive environment chamber are respectively provided with a liquid inlet and a liquid outlet for the corrosive liquid;

[0025] Furthermore, the corrosion solution pool is connected to the liquid inlet of the peristaltic pump through a pipeline, and the liquid outlet of the peristaltic pump and the outlet pipeline of the air pump are connected to the liquid inlet of the corrosion environment chamber through the pipeline after merging.

[0026] Furthermore, the liquid outlet of the corrosive environment chamber is connected to the liquid inlet of the solenoid valve through a pipeline, and the liquid outlet of the solenoid valve is connected to the corrosive waste liquid pool through a pipeline.

[0027] The present invention also provides a method for using the in-situ localized corrosion system on a metal surface, comprising the following steps:

[0028] S1: Install the corrosion environment chamber on the corroded surface of the metal structure;

[0029] S2: Input clean water into the corrosive environment chamber through a peristaltic pump to verify the sealing, and then drain the liquid;

[0030] S3: Install an optical microscope to focus on the surface of the metal structure being tested and observe the metal surface in situ;

[0031] S4: The peristaltic pump, air pump and solenoid valve are intermittently started and stopped through the control module, and the soaking cycle and the drying cycle are performed alternately until the local corrosion of the metal structure surface is completed.

[0032] Furthermore, in step S4, when the immersion cycle begins, the solenoid valve and the peristaltic pump are opened to allow the corrosive liquid to fill the corrosive environment chamber, and the solenoid valve is closed until the immersion cycle ends.

[0033] Furthermore, in step S4, when the drying cycle starts, the solenoid valve and the air pump are opened to drain the corrosive liquid from the corrosive environment chamber, and the air pump is continuously operated until the drying cycle ends.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) The present invention can form a local corrosion environment on the surface of the metal structure being tested by filling the corrosion environment chamber with air or corrosive medium through the cooperation of a peristaltic pump and an air pump; in addition, an optical microscope can be directly focused on the surface of the metal structure in the corrosion environment chamber to achieve in-situ observation of the local corrosion test of the metal structure.

[0036] (2) The present invention uses a peristaltic pump to transport corrosive media and an air pump to transport air. The two pipelines converge and connect to the corrosive environment chamber. A solenoid valve is installed behind the liquid outlet of the corrosive environment chamber to control the pipeline switch. The above three devices are all connected to a control system, and local intermittent corrosion of the metal surface is achieved by adjusting the cycle of liquid and air intake.

[0037] (3) The present invention can realize in-situ observation of local corrosion and corrosion process of large metal structures, without the need to place the entire metal structure in a corrosion environment chamber as in traditional metal corrosion methods, and the size requirement of the corrosion environment chamber is relatively small.

[0038] (4) The optical microscope of the present invention can be flexibly arranged outside the corrosion environment chamber, and can realize in-situ observation by directly focusing on the surface of the metal structure, and can judge the degree of corrosion through the collected and transmitted pictures.

[0039] (5) The in-situ localized corrosion system of metal surfaces of the present invention provides a universal system and research method applicable to localized corrosion of various types of metal surfaces, which is expected to promote research progress in related fields such as metal component defects and localized corrosion, and has industrial application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic structural diagram of the in-situ localized corrosion system of a metal surface according to the present invention.

[0041] Figure 2 It is a schematic structural diagram of the corrosion environment chamber of the present invention.

[0042] Figure 3 It is a schematic diagram of the connection between the corrosion environment chamber and the metal structure of the present invention.

[0043] Figure 4 This is a microscope image of the metal before corrosion in Example 3 of the present invention.

[0044] Figure 5 This is a microscope image of the metal after corrosion in Example 3 of the present invention.

[0045] Description of the markings in the figure:

[0046] 1-metal structure, 2-corrosion environment chamber, 21-water inlet pipe, 22-water outlet pipe, 23-fixing strap, 24-acrylic shell, 25-rubber waterproof pad, 3-optical microscope, 4-corrosion solution tank, 5-peristaltic pump, 6-air pump, 7-corrosion waste liquid tank, 8-solenoid valve, 9-control module. DETAILED DESCRIPTION

[0047] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0048] Unless otherwise specified, the reagents, methods, instruments and equipment used in the present invention are conventional reagents, methods, instruments and equipment in the art. Unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0049] In the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention; the terms "first", "second", and "third" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance; in addition, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0051] Embodiment 1:

[0052] This embodiment provides a metal surface in-situ localized corrosion system, such as Figure 1 As shown, it is used to locally corrode the metal structure 1. The in-situ local corrosion system of the metal surface of this embodiment includes: a corrosion environment chamber 2 installed on the corroded surface of the metal structure 1; an optical microscope 3 for observing the metal structure 1 through the corrosion environment chamber 2; a corrosion solution pool 4 for providing corrosion liquid; a peristaltic pump 5 for inputting the corrosion liquid in the corrosion solution pool 4 into the corrosion environment chamber 2; an air pump 6 for inputting air into the corrosion environment chamber 2; a corrosion waste liquid pool 7 for recovering the corrosion liquid; an electromagnetic valve 8 provided between the liquid outlet of the corrosion environment chamber 2 and the corrosion waste liquid pool 6; and a control module 9 for controlling the peristaltic pump 5, the air pump 6 and the electromagnetic valve 8.

[0053] In this embodiment, the peristaltic pump 5 and the air pump 6 can be used to fill the corrosive environment chamber 2 with air or corrosive medium, so as to form a local corrosive environment on the surface of the tested metal structure 1, thereby achieving local corrosion of the metal. In addition, the optical microscope 3 can be directly focused on the surface of the metal structure 1 in the corrosive environment chamber 2, so as to achieve in-situ observation of the local corrosion test of the metal structure 1.

[0054] Embodiment 2:

[0055] This embodiment provides a metal surface in-situ local corrosion system and a method of using the same, which are used to perform local corrosion on a metal structure 1. Figure 1 As shown, the metal surface in-situ localized corrosion system of this embodiment includes a corrosion environment chamber 2, an optical microscope 3, a corrosion solution pool 4, a peristaltic pump 5, an air pump 6, a corrosion waste liquid pool 7, a solenoid valve 8 and a control module 9. Among them, the control module 9 is used to control the start and stop of the optical microscope 3, the peristaltic pump 5, the air pump 6 and the solenoid valve 8.

[0056] The corrosive environment chamber 2 is installed on the corroded surface of the metal structure 1. Its specific structure and installation method are as follows: Figure 2-3 Specifically, the basic structure of the corrosion environment chamber 2 is an acrylic shell 24 wrapped on five sides, which is fixed to the surface of the corroded metal structure 1 with a strap 23, and connected to the water inlet pipe 21 and the water outlet pipe 22 through openings at both ends, and a rubber waterproof pad 25 is bonded to the edge of one side of the opening with a sealant.

[0057] like Figure 1 As shown, a transparent observation window is provided on the side of the corrosion environment chamber 2 facing the optical microscope 3. The diameter of the observation window is 25-35 mm and the material of the observation window is quartz glass. The optical microscope 3 is composed of a coaxial light source, a microscopic optical path, a telephoto objective lens and a CCD camera, and is used to observe the local corrosion of the surface of the metal structure 1 through the corrosion environment chamber 2. Among them, the graphic data collected by the CCD camera is transmitted to the control module 9.

[0058] The corrosive solution pool 4 is used to provide corrosive liquid, and the peristaltic pump 5 is used to input the corrosive liquid in the corrosive solution pool 4 into the corrosive environment chamber 2. The air pump 6 is used to input air into the corrosive environment chamber 2. The liquid outlet of the peristaltic pump 5 and the liquid outlet of the air pump 6 are both provided with a one-way valve. The inlet and outlet of the corrosive liquid are respectively provided on both sides of the corrosive environment chamber 2. The corrosive solution pool 1 is connected to the liquid inlet of the peristaltic pump 5 through a pipeline, and the liquid outlet of the peristaltic pump 5 and the outlet pipeline of the air pump 6 are connected to the liquid inlet of the corrosive environment chamber 2 through a pipeline after merging. The corrosive waste liquid pool 7 is used to recover the corrosive liquid, and a solenoid valve 8 is provided between the liquid outlet of the corrosive environment chamber 2 and the corrosive waste liquid pool 6. The liquid outlet of the corrosive environment chamber 2 is connected to the liquid inlet of the solenoid valve 8 through a pipeline, and the liquid outlet of the solenoid valve 8 is connected to the corrosive waste liquid pool 7 through a pipeline.

[0059] The method for using the metal surface in-situ localized corrosion system of this embodiment specifically includes the following steps:

[0060] S1: Install the corrosion environment chamber 2 on the corroded surface of the metal structure 1;

[0061] S2: Input clean water into the corrosive environment chamber 2 through the peristaltic pump 5 to verify the sealing, and then drain the liquid;

[0062] S3: installing an optical microscope 3 so that it focuses on the surface of the metal structure 1 to be tested, and performing in-situ observation of the metal surface;

[0063] S4: The peristaltic pump 5, the air pump 6 and the solenoid valve 8 are intermittently started and stopped by the control module 9, and the immersion cycle and the drying cycle are performed alternately until the local corrosion of the surface of the metal structure 1 is completed. At the beginning of the immersion cycle, the solenoid valve 8 and the peristaltic pump 5 are opened to fill the corrosive environment chamber 2 with the corrosive liquid, and the solenoid valve 8 is closed until the immersion cycle ends. At the beginning of the drying cycle, the solenoid valve 8 and the air pump 6 are opened to empty the corrosive environment chamber 2 with the corrosive liquid, and the air pump 6 is continuously operated until the drying cycle ends.

[0064] Embodiment 3:

[0065] The present embodiment provides a metal surface in-situ localized corrosion system and a method for using the same. The metal surface in-situ localized corrosion system of the present embodiment is composed of a corrosion solution pool 4, a corrosion waste liquid pool 7, a peristaltic pump 5, an air pump 6, an optical microscope 3, an electromagnetic valve 8, a corrosion environment chamber 2, and a control module 9. The corrosion solution pool 4 is connected to the liquid inlet of the peristaltic pump 5 through a pipeline, and the pipeline connected to the liquid outlet of the peristaltic pump 5 and the outlet pipeline of the air pump 6 are converged and connected to the liquid inlet of the corrosion environment chamber 2, and the liquid outlet of the corrosion environment chamber 2 is connected to the liquid inlet of the electromagnetic valve 8 through a pipeline, and the liquid outlet of the electromagnetic valve 8 is connected to the corrosion waste liquid pool 7 through a pipeline. The peristaltic pump 5, the air pump 6, the optical microscope 3, and the electromagnetic valve 8 are connected to the control module 9 through a pipeline.

[0066] The corrosion environment chamber 2 of this embodiment is fixed to the surface of the metal structure 1 being tested using a switch-type magnetic seat or a strap. The corrosion environment chamber 2 is a box-shaped structure with one side open, and the overall material is resin. The upper wall shell of the corrosion environment chamber 2 is bonded with a transparent observation window made of quartz glass, specifically a circular observation window with a diameter of 30 mm. The side wall has a liquid inlet and a liquid outlet on two opposite sides, the bottom is open and has an annular sealing groove at the edge and is connected to a rubber sealing gasket. The shape of one side of the annular rubber sealing gasket is consistent with the bottom of the corrosion environment chamber 2, and the shape of the other side is consistent with the surface of the metal structure 1 being tested. The peristaltic pump 5 and the air pump 6 are both equipped with a one-way valve at the liquid outlet to prevent the liquid in the pipeline from flowing back to contaminate the corrosion solution pool 4 or damage the instrument.

[0067] The optical microscope 3 of this embodiment is composed of a coaxial light source, a microscopic optical path, a telephoto objective lens and a CCD camera, and is fixed to the outside of the tested metal structure 1 using a tripod, and transmits the graphic data collected by the CCD camera to the control module 9 in real time.

[0068] The control module 9 of this embodiment is a computer, which is connected to the peristaltic pump 5, the air pump 6, the solenoid valve 8 and the CCD camera on the microscope 3 using a USB data cable, and controls the corresponding components. Its functions include controlling the start and stop of the peristaltic pump 5, controlling the start and stop of the air pump 6, controlling the opening and closing of the solenoid valve 8, and controlling the CCD camera on the microscope 3 to take pictures.

[0069] The method of using the metal surface in-situ localized corrosion system of this embodiment is specifically as follows:

[0070] Use a strap or a magnetic base to fix the corrosion environment chamber 2 to the surface of the tested metal structure 1. Open the solenoid valve 8 and the peristaltic pump 5 through the control module 9 to pump clean water into the corrosion environment chamber 2. After the clean water is filled, close the solenoid valve 8 and let it stand for inspection to ensure that the test device does not leak.

[0071] Install the optical microscope 3 so that it can penetrate the transparent top cover of the corrosion environment chamber 2 and focus on the surface of the metal structure 1 under test, confirm from the control module 9 that the image acquisition is clear, and start recording.

[0072] The solenoid valve 8 and the air pump 6 are opened through the control module 9 to drain the residual liquid in the pipeline.

[0073] The intermittent immersion test program is set by the control module 9, and the peristaltic pump 5, the air pump 6 and the solenoid valve 8 are automatically started and stopped intermittently according to the test cycle requirements. At the beginning of the immersion cycle, the solenoid valve 8 and the peristaltic pump 5 are opened to allow the corrosive medium to fill the corrosive environment chamber 2, and then the solenoid valve 8 is closed until the end of the immersion cycle. At the beginning of the drying cycle, the solenoid valve 8 and the air pump 6 are opened to empty the corrosive environment chamber 2, and the air pump 6 is continuously operated until the end of the drying cycle.

[0074] By regularly checking the microscopic image displayed on the control module 9, it is determined whether the local corrosion degree of the surface of the tested metal structure 1 meets the requirements. If the requirements are met, the solenoid valve 8 and the air pump 6 are opened to drain the residual liquid in the pipeline, the control module 9 is closed, the corrosive environment chamber 2 is removed, and the local corrosion of the metal surface ends.

[0075] In this embodiment, a 5% concentration neutral NaCl solution was used to corrode the surface of the cast magnesium alloy ZM6 for 3 cycles at 25° C., with 6 hours of immersion and 6 hours of drying as one cycle. Figure 4 and Figure 5 The images taken with microscope 3 are respectively of the corrosion situation before and after. It can be clearly seen that white corrosion products are formed on the surface of the magnesium alloy, indicating that this method is real and effective.

[0076] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A metal surface in-situ local corrosion system, used for local corrosion of a metal structure (1), characterized in that: include: A corrosive environment chamber (2) installed on the corroded surface of a metal structure (1); An optical microscope (3) for observing a metal structure (1) through a corrosive environment chamber (2); A corrosion solution tank (4) for providing a corrosion solution; A peristaltic pump (5) for inputting the corrosive solution in the corrosive solution pool (4) into the corrosive environment chamber (2); An air pump (6) for inputting air into the corrosive environment chamber (2); A corrosion waste liquid pool (7) for recovering the corrosion liquid; A solenoid valve (8) disposed between the liquid outlet of the corrosive environment chamber (2) and the corrosive waste liquid pool (6); A control module (9) is used to control a peristaltic pump (5), an air pump (6) and a solenoid valve (8).

2. A metal surface in-situ localized corrosion system according to claim 1, characterized in that: The corrosive environment chamber (2) is installed on the surface of the metal structure (1) using a switchable magnetic seat or a binding strap.

3. The in-situ localized corrosion system for metal surface according to claim 1, characterized in that: The corrosive environment chamber (2) is a box-shaped structure with one side open; A sealing groove is arranged around a surface of the corrosive environment chamber (2) in contact with the metal structure (1), and a sealing gasket capable of being sealed and connected to the sealing groove is arranged on the surface of the metal structure (1).

4. The in-situ localized corrosion system for metal surface according to claim 1, characterized in that: The corrosion environment chamber (2) is provided with a transparent observation window on a side facing the optical microscope (3); The diameter of the observation window is 25-35 mm, and the material of the observation window is quartz glass.

5. The in-situ localized corrosion system for metal surface according to claim 1, characterized in that: The optical microscope (3) is composed of a coaxial light source, a microscopic optical path, a telephoto objective lens and a CCD camera; The graphic data collected by the CCD camera is transmitted to a control module (9).

6. The in-situ localized corrosion system for metal surface according to claim 1, characterized in that: The liquid outlet of the peristaltic pump (5) and the liquid outlet of the air pump (6) are both provided with a one-way valve.

7. The in-situ localized corrosion system for metal surface according to claim 1, characterized in that: The two sides of the corrosive environment chamber (2) are respectively provided with a liquid inlet and a liquid outlet for the corrosive liquid; The corrosive solution pool (1) is connected to the liquid inlet of the peristaltic pump (5) through a pipeline, and the liquid outlet of the peristaltic pump (5) and the outlet pipeline of the air pump (6) are connected to the liquid inlet of the corrosive environment chamber (2) through a pipeline after merging.

8. The in-situ localized corrosion system for metal surface according to claim 7, characterized in that: The liquid outlet of the corrosive environment chamber (2) is connected to the liquid inlet of the electromagnetic valve (8) through a pipeline, and the liquid outlet of the electromagnetic valve (8) is connected to the corrosive waste liquid pool (7) through a pipeline.

9. A method for using the metal surface in-situ localized corrosion system according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1: installing the corrosive environment chamber (2) on the corroded surface of the metal structure (1); S2: Input clean water into the corrosive environment chamber (2) through the peristaltic pump (5), verify the sealing, and then drain the liquid; S3: installing an optical microscope (3) so that it is focused on the surface of the metal structure (1) to be tested, and performing in-situ observation of the metal surface; S4: The peristaltic pump (5), the air pump (6) and the solenoid valve (8) are intermittently started and stopped through the control module (9), and the soaking cycle and the drying cycle are performed alternately until the local corrosion of the surface of the metal structure (1) is completed.

10. The method for using the in-situ localized corrosion system for metal surface according to claim 9, characterized in that: In step S4, when the soaking cycle starts, the solenoid valve (8) and the peristaltic pump (5) are opened to allow the corrosive liquid to fill the corrosive environment chamber (2), and the solenoid valve (8) is closed until the soaking cycle ends; When the drying cycle begins, the solenoid valve (8) and the air pump (6) are opened to drain the corrosive liquid from the corrosive environment chamber (2), and the air pump (6) is continuously operated until the drying cycle ends.

Images