Exploring the Benefits of Salt Spray Tests and Chambers for Corrosion Resistance

Salt spray test chamber is also called salt spray testing machine, which is called salt spray testing machine in full, and is mainly used to test the corrosion resistance of samples. At present, it is widely used in industries such as aerospace industry, automotive electronics, electronic and electrical engineering, mobile digital, plastic products, metal materials, etc., to test its corrosion resistance and simulate extreme situations under natural or working conditions, in order to understand the performance temperature situation of each sample.

LISUN Salt Spray Test Chamber | Salt Fog Test | ASTM B117 Salt Spray ChamberSalt Spray Test Chamber is applicable to the salt spray corrosive test for the protection layer of components, parts, electronic and electrical parts and metal materials and industrial products. The salt fog test chamber meets the following standards: IEC60068-2-11 (GB/T2423.17), GB/T10125, GB/T1771, ISO9227, ASTM-B117, GB/T2423-18, QBT3826, QBT3827, IEC 60068-2-52, ASTM-B368, MIL-STD-202, EIA-364-26, GJB150, DIN50021-75, ISO3768, 3769, 3770; CNS 3627, 3885, 4159, 7669 etc.

The current salt spray test chamber has evolved from a simple neutral salt spray test to various forms such as acetate spray test, copper salt accelerated acetate spray test, and alternating salt spray test. China has also adopted salt spray testing as a national standard and provided detailed regulations.

I. Working principle of salt spray test chamber:
The working principle of the salt spray test chamber is relatively simple. It is mainly to compress the corrosive solution into air spray, spray the sample, and wrap the spray on all sides of the sample as much as possible. This test can be carried out continuously or circularly until the sample is corroded. Then record the corrosion time as the corrosion resistance of the sample. The longer the time is, the better the corrosion resistance of the sample is.

Generally, the corrosion solution in the salt spray test chamber is mainly 5% sodium chloride solution or 0.26 g Copper(II) chloride is added per liter of sodium chloride solution as the salt spray corrosion solution. In addition, the salt spray test chamber can independently regulate the settling and spraying amount of salt spray, ensuring a constant test temperature, convenient operation, and stable test environment. Therefore, it is often used to test the corrosion resistance of daily Household goods or industrial products.

The test chamber can reach any temperature point from room temperature to 50 ℃ within the test workspace and maintain a constant temperature. Conduct salt spray corrosion tests on materials or products within a specified volume of the box, with constant temperature and relative humidity. The material used for manufacturing this equipment is imported corrosion-resistant PVC plastic sheet, which does not react with saline or acidic saline solutions and does not affect the test results. In the design work of this equipment, the internal and external pressure is balanced, and the salt mist freely settles in the box, and can be adjusted to the range specified by national standards.

II. Salt spray test

1. Prepare a 5% saline test solution. Take 13.3 liters of pure distilled water from a measuring cup, add 700g of industrial salt sodium chloride (NaCl) to the pure distilled water, and stir evenly.

2. Use a measuring cup to add the prepared saline test solution to the inlet of the liquid medicine test in batches, allowing the saline test solution to flow into the saline preheating tank.

3. Place the test sample on the shelf. Before the test, the surface of the test sample must be clean, free from oil stains, and have no temporary protective layer.

4. Turn on the power switch of the saline spray tester, set the laboratory temperature to 35 ℃, the pressure tank temperature to 45 ℃, and set the test time to 12 hours. Turn on the instant spray switch and the timed spray switch. Start spray, salt water spray test starts, 12 hours later, salt water spray test machine will automatically shut down, and salt spray test ends. If there are special requirements for experimental time in the customer supply contract, the contract shall be followed.

5. After the test is completed, gently wash off the salt deposits on the surface of the test sample with flowing water, and then rinse in distilled water. The washing water temperature should not exceed 35 ℃, and then place it in the indoor atmosphere.

III. The application of the Salty spray test chamber
The actual application of salt spray test box: Artificial simulation of salt spray test includes neutral salt spray test, acetic acid salt spray test, copper salt accelerated acid salt spray test and cyclic salt spray test.

1. Neutral salt spray test (NSS test) is the earliest and most widely used accelerated corrosion test. It uses 5% sodium chloride solution, and the pH value of the solution is adjusted to the neutral range (6-7) as spraying solution. The test temperature is 35°C, and the settling rate of salt fog is required to be between 1-2ml/80cm2.h.

2. Acetic acid salt spray test (ASS test) is developed on the basis of the neutral salt spray test. Some acetic acid is added to the 5% sodium chloride solution to reduce the PH value of the solution. The deep solution turns into acid, and the finally formed salt fog changes from neutral to acetic acid. Its corrosion speed is three times faster than that of the NSS test.

3. Copper salt accelerated acetic acid salt spray test (CASS test) is a newly developed rapid salt fog corrosion test abroad. The test temperature is 50°C, and a small amount of copper salt-copper chloride is added to the salt solution to strongly induce corrosion. Its corrosion speed is about 8 times faster than that of the NSS test.

4. The alternating salt spray test is a comprehensive salt spray test. In fact, it is a neutral salt spray test plus a constant wet heat test. It is mainly used for cavity type complete machine products. Through the infiltration of wet and hot environment, salt spray corrosion is not only produced on the product surface, but also in its interior. It tests the electrical performance and mechanical properties of the complete machine product by alternating the product between salt spray and wet heat environment.

Tags：YWX/Q-010