Multi-angle rotary experimental equipment for erosion corrosion of high-temperature saline solution

Abstract

The utility model provides multi-angle rotary experimental equipment for erosion corrosion of a high-temperature saline solution. The device is made of customized acrylic materials, a JJ-1B type motor is selected as a rotating motor, the diameter of a rotating disc is 100 mm, and three kinds of rotating discs with different impact angles are manufactured in total. The centers of the samples are fixed on a rotary erosion corrosion device through bolts, three parallel samples are arranged in each group, the experiment temperature is 80 + / -5 DEG C, and the experiment time is 120 hours. The experimental medium is deionized water and a 3.5% NaCl solution. The erosion corrosion resistance of the material can be further analyzed by recording weight change results and weightlessness experiment results of different samples.

Description

Technical Field

[0001] The utility model discloses a multi-angle rotating experimental device for high-temperature salt solution erosion corrosion, which relates to an experimental device and a method for measuring high-temperature erosion corrosion resistance performance by using the device. Background Art

[0002] Stainless steel has good mechanical properties and easy processing performance. It also has many advantages such as corrosion resistance and oxidation resistance. It has been widely used in the field of nuclear power. However, during the operation of nuclear power plants, stainless steel will corrode when it is eroded by acid and alkali media, especially under alkaline conditions with high pH values. It is easy to passivate. In order to solve this problem, nuclear power plants use martensitic stainless steel to process pump impellers, and use magnetic rotors to drive the workpieces to rotate at high speed in high-temperature salt-rich solutions for corrosion experiments. Erosion corrosion is a common metal damage phenomenon caused by the interaction between metal surfaces and corrosive fluids under high-speed relative motion, in which mechanical wear plays a major role. Existing studies have shown that there are factors that affect the erosion corrosion rate, such as liquid flow rate, fluid sand content, scouring angle, fluid pH value, solution temperature, material composition, material microstructure and heat treatment system. In order to test the service life and safety of the reactor, it is necessary to study the cavitation and erosion behavior of the workpiece alloy material. According to the standards "SY / T 7394-2017 Recommended Practice for Erosion and Wear Assessment of Pipeline Systems", "GB / T 6383-2009 Vibration Cavitation Test Method" and "GB / T 40299-2021 Applicable Practice for Electrochemical Measurement Methods for Metal and Alloy Corrosion Tests", and combined with the service conditions of the martensitic stainless steel impeller in the power plant, the high-temperature erosion and corrosion assessment method of the stainless steel workpiece is determined, and the high-temperature erosion and corrosion resistance of the reactor stainless steel workpiece is tested by the utility model erosion and corrosion experimental rotating erosion and corrosion test device. Summary of the invention

[0003] In response to the above needs, the utility model proposes a multi-angle rotating experimental equipment for high-temperature salt solution erosion corrosion. The corrosion environment under different working conditions is simulated, including parameters such as high temperature, high pressure, and fluid velocity, and the corrosion resistance of parts with different materials, coatings, and structures is evaluated. The coating includes a surface coating and an inner coating. The corrosion performance of different design schemes is evaluated, including different angles of attack and rotation, potential corrosion problems are discovered, and corresponding preventive measures are taken.

[0004] The utility model first proposes a multi-angle rotating experimental equipment for high-temperature salt solution erosion corrosion. The technical solution described in the utility model is achieved as follows:

[0005] The utility model discloses a multi-angle rotary experimental device for high-temperature salt solution erosion corrosion, characterized in that it comprises a sample holder (1), a motor (2), a sample (3), a water bath (4), an experimental solution (5), a fixed holder (6) and refractory bricks (7); the experimental sample (3) is placed on the sample clamp at the angle required for the experiment; the motor (2) fixed to the fixed holder (6) drives the sample holder (1) to rotate, and the sample is subjected to a high-temperature erosion corrosion test in the experimental solution (5) heated by the water bath (4); the surface of the sample is flush with the fixed surface of the device, and after the experimental solution is heated to the experimental temperature, the sample holder, the motor and the fixed holder are fixed; the motor performs the high-temperature erosion corrosion test at a certain wheel linear speed.

[0006] The sample holder and sample fixing device of the utility model is in the shape of a disc with a diameter of 100 mm, and is characterized in that: the sample holder (1) is integrally formed of acrylic material, a JJ-1B motor is selected as the motor (2), and three sample holders (1) with discs of different impact angles are manufactured, providing more accurate conditions for the test. The sample fixing device of the sample holder (1) is made of transparent bolts made of acrylic material to prevent galvanic corrosion during the experiment.

[0007] The sample size of the utility model is a 55mm×10mm×2mm cuboid. The sample is ground and polished with 180#, 400#, and 800# metallographic sandpaper, and then ultrasonically cleaned with anhydrous ethanol and blown dry to prevent interference from oil and the like.

[0008] The measurement method described in the utility model is to record the initial weight as m0 and the weight after corrosion as m i , erosion corrosion is usually manifested as corrosion weight loss; m0 is the standard weight before the experiment, m i is the weight of the substance after the i-th experiment.

[0009] Data analysis is to calculate the weight loss ratio Δm, which is expressed by formula 1. The value calculated by this formula represents the weight ratio consumed by the object during the experiment. According to the measurement records of the experimental process, the weight change results of different samples and the weight loss test results are obtained to analyze the material's anti-erosion and corrosion performance:

[0010]

[0011] The advantage of the utility model is that the multi-angle rotary experimental equipment for high-temperature salt solution erosion corrosion and its measurement method provide simulate the high-temperature and high-pressure corrosion environment inside the reactor. By simulating actual working conditions in a laboratory environment, the corrosion resistance of the reactor equipment can be effectively evaluated, and potential corrosion problems can be discovered in advance, so that corresponding preventive measures can be taken. In specific applications, the high-temperature salt solution erosion corrosion experimental equipment can be used to evaluate and improve the performance of materials, structures, coatings, etc. of key components of the reactor, further improve the safety, stability and reliability of the reactor, and reduce possible environmental pollution and casualties. The equipment can provide important experimental data and references for the research and development and design of reactors. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The utility model has two drawings, in which:

[0013] Attached Figure 1 It is a schematic diagram of the structure of the utility model;

[0014] Attached Figure 2 For attachment Figure 1 Schematic diagram of the fixing device of the disc part of the sample holder and the size diagram of the test sample used in the utility model;

[0015] In the attached Figure 1 In: 1. sample holder 2. motor 3. specimen 4. water bath 5. experimental solution 6. fixed holder 7. refractory brick. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the utility model clearer, the device is tested to evaluate its correctness and health status to ensure the reliability and stability of the device in practical applications. The device structure and measurement method of the utility model will be further described below.

[0017] Example 1

[0018] The specific implementation example of the utility model is shown in the attached figure. Figure 1 As shown, it is characterized in that the multi-angle rotary erosion corrosion test equipment includes a sample holder 1, a motor 2, a sample 3, a water bath 4, an experimental solution 5, a fixed holder 6, and a refractory brick 7; the utility model is experimentally verified to ensure its normal operation, and the implementation method is as follows:

[0019] As shown in Tables 1 and 2, a comparative test of three material systems was designed, taking the martensitic stainless steel matrix material, laser cladding layer material, and composite sample containing both matrix and cladding metal used in the reactor as examples. The dimensions of sample 3 are as shown in the attached figure. Figure 2The sample shown is 55mm×10mm×2mm. After being polished with 180#, 400#, and 800# metallographic sandpaper, it is ultrasonically cleaned with anhydrous ethanol and then blown dry to prevent interference from oil and other pollutants.

[0020] Experimental solution 5 used a two-solution system of deionized water and 3.5% NaCl;

[0021] The surface of the sample 3 is flush with the fixed surface of the disc-shaped device with a diameter of 100 mm. Figure 2 The fixtures for three different impact angles, 0°, 45° and 90°, are shown. The center of the specimen is fixed to the rotating erosion corrosion device by bolts.

[0022] After the experimental solution 5 is heated to the experimental temperature of 80±5°C, the sample holder 1, the motor 2 and the fixed holder 6 are fixed, and the equipment and the timer are turned on;

[0023] Motor 2 was subjected to a high temperature erosion corrosion test for 120 hours at a rotation speed of 300 r / min and a corresponding linear speed of 2 m / s.

[0024] After the test time is reached, take out the sample, wash it with anhydrous ethanol, dry it with a hair dryer, weigh it after drying for 1 minute, dry it again for 2 minutes and weigh it again until the difference between the two weighing readings is less than 0.5 mg. Take the average value of multiple weighings and record the weighing data.

[0025] The initial weight is recorded as m0, and the weight after corrosion is recorded as m i (i=6h, 12h, 24h...), erosion corrosion is usually manifested as corrosion weight loss, weight loss ratio Δm= (m0-m i ) / m0. Where m0 is the standard weight before the experiment, m i is the weight of the substance after the i-th experiment;

[0026] The weight loss ratio Δm shown in Table 3 was calculated based on the experimental data. The material anti-erosion and corrosion performance was analyzed by combining the weight change results of different samples with the characterization experimental results to verify the reliability of the experimental device.

[0027] Under the experimental condition that the impact angle of the deionized water environment is set to 45°, only a small amount of corrosion pits appeared on both the coating and the substrate, and the difference was not obvious; under the experimental conditions that the impact angle of the deionized water environment is set to 0° and 90°, it was found that obvious corrosion pits and NaCl crystal particles appeared on the surface of the sample; under the experimental condition that the impact angle of the 3.5% NaCl solution environment is set to 45°, obvious and large corrosion pits appeared at the junction of the coating and the substrate. The above-mentioned characterization phenomenon is consistent with the trend of the weight loss ratio change of different samples in Table 3, which proves that the device structure and measurement method of the utility model can effectively simulate the high temperature and high pressure corrosion environment inside the reactor, and effectively evaluate the corrosion resistance of the reactor equipment.

[0028] The above is only a preferred embodiment of the utility model and does not have any limiting effect on the utility model. Any technician in the relevant technical field, without departing from the scope of the technical solution of the present invention, makes any form of equivalent replacement or modification to the technical solution and technical content disclosed in the utility model, which does not depart from the content of the technical solution of the utility model and still falls within the protection scope of the utility model.

[0029]

[0030]

[0031]

Claims

1. A multi-angle rotating experimental equipment for high temperature salt solution erosion corrosion, characterized in that: The invention comprises a sample holder (1), a motor (2), a sample (3), a water bath (4), an experimental solution (5), a fixed holder (6) and refractory bricks (7); the experimental sample (3) is placed on the sample holder at an angle required for the experiment; the motor (2) fixed by the fixed holder (6) drives the sample holder (1) to rotate, and the sample is subjected to a high-temperature erosion corrosion test in the experimental solution (5) heated by the water bath (4).

2. The multi-angle rotating experimental equipment for high-temperature salt solution erosion corrosion according to claim 1, characterized in that: The sample holder (1) is integrally formed of acrylic material, a JJ-1B motor is selected as the motor (2), and three sample holders (1) with discs having different impact angles are manufactured, providing more precise conditions for the test.

3. The multi-angle rotating experimental equipment for high temperature salt solution erosion corrosion according to claim 2, characterized in that: The sample fixing device of the sample holder (1) uses transparent bolts made of acrylic material to prevent galvanic corrosion during the experiment.

Images