Neutral salt spray test is to put the sample exposed to a neutral sodium chloride atmosphere to the specified time. And then assess the blistering, rust grade and corrosion spread distance on its surface. It is one of the currently used method to test the corrosion resistance of the coating by CAMELSTEEL.
The neutral salt spray test of color coated steel coil is carried out by special salt spray test chamber. The salt spray test chamber simulates the natural environment of the atmosphere. Providing the specimen with the temperature range, the settling volume of salt mist and the accelerated corrosion environment of the test period specified by salt spray corrosion.
Check the phenomenon of destruction in the sample. Including blistering, rust, the decrease of adhesion and spread caused by the corrosion of scratches, and stipulate according to GB/T 1766-1995 standards. Use 0, 1, 2, 3, 4, 5 six levels to assess the extent of their damage. When evaluating its foaming grade, rust grade after test, worst value of parallel samples should be taken as test results.
2. Humidity resistance test.
Humidity resistance test, also known as wet test. It is used to evaluate the coating’s resistance to high temperature and high humidity. It’s also a measurement to test the corrosion resistance of a coating. Therefore, it usually carry out simultaneously with the salt spray test.
As the most important factor in the humidity resistance test is the temperature and humidity. So the regulate and control of these two indexes in temperature and humidity regulator should be paid special attention in the whole process of each test so as not to affect the test results.
Humidity resistance test is usually carried out in two ways, one is condensing damp heat method, and the other is non-condensing damp heat method. For the evaluation of the sample, mainly according to GB / T 1766-1995 standard to observe the grade of coating blistering, cracking, rusting and shedding, using the worst value of parallel samples for the test results.