The neutral salt spray test is to expose the sample to a neutral sodium chloride atmosphere for a specified period of time to evaluate its surface blistering, rust level and corrosion propagation distance. The neutral salt spray test is one of the methods commonly used to test the corrosion resistance of coatings.
The salt spray test of the color-coated steel plate is carried out through a special salt spray Test Chamber (Figure 4-17). Periodic accelerated corrosion environment, check the damage phenomenon of the sample, including blistering, rust, adhesion loss and corrosion spread from scratches, etc., and comply with the GB/T 1766-1995 standard. Use 0, 1, 2, 3, 4, 5 to rate the degree of damage. For the test conditions of the salt spray box in this test, the humidity is required to be kept at 35°±2°; the concentration of the sodium chloride solution configured is (50±5) g/L; the pH value is 6.5~7.2; calculated after a 24h cycle The solution collected by each collector should be 1.0~2.0mL/h per 80cm² area. When evaluating the blister level and rust level after the test, the worst value of the parallel samples should be taken as the test result.
