The salt spray settling rate in the salt spray test chamber refers to the amount of salt spray settled per unit area per unit time, which is an important parameter of the salt spray test, reflecting the characteristics of spray density and uniformity. Corrosion of the salt spray test, in addition to the role of chloride ions in the corrosive medium, is also affected by the diffusion of oxygen in the liquid film on the metal surface. The finer the salt spray particles, the larger the surface area formed, and the more oxygen is adsorbed, the stronger the corrosivity. In nature, more than 90% of the salt spray particles have a diameter of 1 Lm or less. Studies have shown that the amount of oxygen adsorbed on the surface of the salt spray particles with a diameter of 1 Lm is relatively balanced with the amount of dissolved oxygen inside the particles. The salt spray particles are smaller and the amount of oxygen adsorbed does not increase any more. However, if the oxygen in the liquid film is stationary, when the liquid film is in contact with the metal, the metal will corrode quickly, and the oxygen in the liquid film also drops rapidly, causing the corrosion reaction to slow down. If the liquid film is continuously updated, the corrosion will continue. The rate of renewal of the liquid film on the metal surface increases with the increase of the salt spray settling rate in the salt spray test chamber. The salt spray rate is too low, which will affect the renewal rate of the liquid film on the metal surface. When the sedimentation rate is less than 0.3 mL/80 cm 2 · h, the corrosion rate increases as the sedimentation rate increases. This is because the liquid film on the metal surface is thinner and the oxygen quickly reaches the surface of the cathode, so the corrosion rate will slowly rise and gradually stabilize. When the sedimentation rate exceeds 1.2mL/80cm2·h, the liquid film continues to thicken and the oxygen diffuses. As the distance increases, it is difficult to reach the surface of the cathode, and the corrosion rate is not accelerated. Therefore, taking a moderate salt spray settling rate, the corrosion rate is stable, and the test results are reproducible. The salt spray settling rate is usually controlled within the range of 1~2mL/80cm2·h to ensure the correctness of the test results in the salt spray test chamber. Led Floating Globe,Best Illuminated Globe,Illuminated Universe Globe,Illuminated Globe With Stand Ningbo Holly Arts & Crafts Co.,Ltd. , https://www.china-globes.com
Effect of salt spray settling rate on test results in salt spray test chamber