SO₂ as a common harmful gas, its corrosive effect on materials can not be underestimated. Whether it is metal pipes and equipment in the chemical and power industries, or non-metallic materials in the construction and electronics fields, SO₂ erosion may lead to reduced performance, shortened life and even lead to safety accidents.
SO₂ corrosion test chamber came into being, it provides an indispensable means for accurately evaluating the corrosion resistance of materials in SO₂ environment, and becomes a powerful tool for material research and quality control.
SO₂ has a strong chemical activity. When it dissolves in water, it forms H₂SO₃, which further dissociates to produce H +, making the solution acidic. This acidic environment is capable of electrochemical reactions with metals, for example, for metals such as iron, the iron atoms lose electrons to form Fe² + entering the solution, while the hydrogen ions in the solution gain electrons to form hydrogen.
For some non-metallic materials, such as rubber and plastics, SO₂ may penetrate into the interior of the material and react with some chemical components in it, resulting in changes in the molecular structure of the material, thereby reducing the physical properties of the material such as hardness, elasticity, toughness and so on.
SO₂ corrosion test chamber releases SO₂ gas through the steel cylinder, uses heating and humidification devices to adjust the temperature and humidity inside the chamber and keeps it stable by relevant systems, controls the gas concentration with the help of the measuring cylinder buoy, and circulates the gas evenly. SO₂ reacts with atomized water to produce acidic substances to corroze the tested items to test their corrosion resistance. The control system accurately controls the parameters and the test process, and the exhaust gas is discharged after the test through filtration and other purification treatment, so as to realize the simulation test and research on the performance of materials in the SO₂ environment.
For metal materials, the thickness is between a few millimeters and tens of millimeters. During the sampling process, care should be taken to avoid damage or contamination to the surface of the material. After sampling, the sample needs to be pre-treated, such as sanding the metal surface with sandpaper to remove the oxide layer and impurities on the surface, and then cleaning with organic solvents to ensure that the surface is clean. For non-metallic materials, such as plastic or rubber, it is also necessary to cut the sample into the specified size, and clean the surface to remove dust, oil and so on.
The setting of test parameters depends on the type of material, application scenario and test purpose. For metal materials, such as steel, in the general atmospheric environment simulation test, the SO₂ concentration may be set at 50-200 ppm, the temperature is 25°C, the humidity is 70% RH, and the test time can be set to 24-720 hours according to the expected service life of the material or relevant standards.
For metal materials used in high-pollution industrial environments, the SO₂ concentration may be increased to more than 1000 ppm, while increasing the temperature and humidity conditions, and extending the test time. For non-metallic materials, such as coatings, the SO₂ corrosion resistance test, the parameter Settings will be different, the concentration may be relatively low, the test time will be based on the type of coating and application requirements.
First, place the prepared sample carefully on the sample holder in the test chamber to ensure that the sample is securely placed and does not interfere with each other. Then, close the test chamber door and check the seal. Then, according to the set test parameters, turn on the SO₂ gas supply system, adjust the flow rate to the required concentration, and start the temperature and humidity control system to achieve the set temperature and humidity conditions.
During the test, the changes of the sample should be closely observed through the observation window of the test chamber or the monitoring system, and the test data should be recorded regularly, such as temperature, humidity, SO₂ concentration and other environmental parameters, as well as the quality changes of the sample, surface topography changes and other data.
By comparing the microstructure of the sample surface before and after the test, such as whether there are corrosion pits, cholders, material spalling, etc., the corrosion resistance of the material is evaluated. For example, if a large number of evenly distributed small corrosion pits appear on the surface of the metal sample, and the depth of the corrosion pits is shallow, indicating that the material has a certain corrosion resistance, but if the corrosion pits are large and deep, or even penetrating corrosion, it indicates that the corrosion resistance of the material is poor.
The SO₂ corrosion test chamber can accurately simulate the single corrosion environment of SO₂ or the complex environment combined with temperature and humidity and other factors, providing standardized and repeatable conditions for the corrosion resistance test of materials. By precisely controlling parameters such as SO₂ concentration, temperature and humidity, and test time, the corrosion resistance data of materials in a specific environment can be quickly and accurately obtained, which greatly reduces the cycle of material development and quality detection.
Not only a single gas (SO2) is available, but also toxic gas types such as H2S,NO2,CL2, etc., greatly increasing the complexity of the toxic gas environment.MFG test chamber can greatly restore this complex environment.
Moreover, the environmental parameters inside the test chamber can be adjusted at any time, which is convenient to study the corrosion behavior of the material under different conditions, and provides a strong support for the study of the corrosion mechanism of the material.
Although the test chamber has many advantages, it also has some limitations. In the actual environment, materials are often exposed to a variety of pollutants (such as SO₂, nitrogen oxides, particulate matter, etc.) and complex climatic conditions (such as rapid changes in temperature, humidity, light, wind and rain, etc.), and the test chamber is difficult to fully simulate this complex multi-factor synergy.
English
русский
français
العربية
Deutsch
Español
