The important role of the hottest salt spray test

The important role of salt spray test chamber in practice

salt spray test chamber is an important means to assess the salt spray corrosion resistance of products or materials, and the scientificity and rationality of its test results are very important. There are many reasons that affect the stability and consistency of salt spray test results, so to improve the effectiveness of salt spray test results, it is necessary to improve the test technology. Therefore, testers should not only have solid professional knowledge and technology, but also have rich practical experience and comprehensive understanding of products

understand the salt spray test of the salt spray test chamber from the multi-disciplinary fields of chemical and environmental engineering, materials, structures and processes, scientifically and reasonably express the test results, better provide effective information for product material selection, structural design, process selection, product transportation, storage and use, and improve the salt spray corrosion resistance of products or materials

II. The role of salt spray test chamber in practice

salt test conditions: the soil of the plot is clay, and the surface is corn stubble. The ground spray test chamber is an environmental test that mainly uses the salt spray test chamber to create artificial simulated salt spray environmental conditions to assess the corrosion resistance of products or metal materials. It is divided into two categories, one is natural environmental exposure test, and the other is artificial accelerated simulated salt spray environment test. Artificial simulated salt spray environment test is to use a kind of test equipment with a certain volume space - salt spray test chamber, and use artificial methods to create salt spray environment in its volume space to assess the quality of salt spray corrosion resistance of products. Compared with the natural environment, the chlorine degree of its salt spray environment can be several times or dozens of times of the salt spray content of the general natural environment, which greatly improves the corrosion rate. The time to obtain the results of salt spray test on products is also greatly shortened. If a product sample is tested in a natural exposure environment, it may take 1 year to be corroded, while similar results can be obtained in 24 hours under the artificial salt spray environment

salt spray test with salt spray test chamber includes neutral salt spray test, acetate spray test, copper salt accelerated acetate spray test and alternating salt spray test

1. Neutral salt spray test (NSS test) is an accelerated corrosion test method that appeared first and is currently the most widely used in the field. It uses 5% saline solution, and the pH value of the solution is adjusted to the neutral range (6-7) as the solution for spray. The test temperature of 35 ℃ is the key to win the market competition, and the sedimentation rate of salt spray is required to be 1-2ml/80cm2 H

2. Acetate spray test (ASS test) is developed on the basis of neutral salt spray test. It is to add some glacial acetic acid to the 5% saline solution to reduce the pH value of the solution to about 3. The solution becomes acidic, and the final salt mist also changes from neutral salt mist to acid. Its corrosion rate is about 3 times faster than that of NSS test

3. Copper salt accelerated acetate spray test (CASS test) is a rapid salt spray corrosion test developed recently abroad. The test temperature is 50 ℃, and a small amount of copper salt - copper chloride is added to the salt solution to strongly induce corrosion. Its corrosion rate is about 8 times that of NSS test

4. Alternating salt spray test is a comprehensive salt spray test, which is actually a neutral salt spray test plus a constant damp heat test. It is mainly used for cavity type complete machine products. Through the penetration of the humid environment, salt spray corrosion occurs not only on the surface of the product, but also inside the product. It is to significantly improve the comprehensive support ability of new materials in the key field of salt, and to alternate between fog and damp and hot environmental conditions. Finally, it is to assess whether the electrical and mechanical properties of the whole product have changed