NSS test is widely used to test the accelerated steel corrosion. It is in a special test box, and people spray a mist, including 5士0.5% sodium chloride, and 5-7.2 brine whose PH is 6. Try to make the mist on the experimentation and observe its corroding conditions. It has a great request, (35±2)℃, and the humidity is over 95%. Besides, the fog is about 1～2 mL/h. The nozzle pressure is 78.5～137.3 kPa (0.8～1.4 kgf/cm2).
When the experiment ends, put out the sample to dry it 0.5-1 h. Then use the flow water, under 40 degree, to clean it. At last, use the blower to blow it immediately. Experiment result. To meet the demand of the different experiment, different evaluate criterion could be adopted, such as weight variation, microscope observation, and mechanical property. Usually, the evaluate criterion should be put up by the product’s standard.
As for the general test, the routine record should think about the following factors:
a: the outlook after the experiment.
b: the outlook after cleaning the corroding products.
c: the corroding defects, such as the number and distributing of pitting, crackles and bubbles.
d: the time to corrode. People often use the resistant to salt spray test to evaluate the durability.