Chicken cage manufacturers often introduce the equipment after the salt spray test and how the anti-corrosion degree is. Today we will tell you what the salt spray test is. In fact, the salt spray test is to continuously spray the sodium chloride aqueous solution on the test plate in the form of a mist to observe whether the coating film is corroded or not.
Salt spray test chamber
After we opened the salt spray test box, we can see that the test boards standing in the box are arranged in an orderly manner (the steel plate is generally painted with paint).
Compared with fresh water and sea water, sea water is more likely to corrode steel. The salt spray test is a test in which salt water like seawater is continuously sprayed on the test panel to accelerate corrosion.
"Rust" and "corrosion" are actually chemical reactions, and a high temperature environment is also one of the reasons for rusting. Therefore, the set temperature in the salt spray box is 35°C. If the outdoor environment reaches 35 ℃, it is generally in hot weather. Therefore, a harsh and harsh environment like the sweltering heat is created in the salt spray box. The salt spray has been continuously carried out, so the humidity in the salt spray box is 100%.
To what extent will the iron plate in the salt spray box rust?
Let's see how long does it take for ordinary iron plates to rust when sprayed with salt water? If the steel plate (SS400) is directly put into the salt spray tester, the following rust will occur.
It didn't take long for the iron plate to rust, and the salt water in the box accelerated the rate of corrosion. Salt spray test can also be understood as an accelerated corrosion test.
If a test panel with a normal coating film is placed in the salt spray box, we will see this situation, the coating film will swell, and the damaged part of the coating film will also produce red rust. (The photo of the coating film below is not a Robalu Coating product.)
Poor salt spray test results do not mean poor corrosion resistance
The salt spray test is a test specified in GB/T 1771-2007 (Japan is JIS K 5600-7-1 standard).
A good salt spray test result does not mean that the coating has good corrosion resistance. Salt spray test results can only be used as a reference for performance indicators. In addition, as the inspection of paint quality, the results of salt spray test also have certain reference significance.
Let's take a look at the results of a salt spray test for hot dip galvanizing.
After 1008 hours, some red rust appeared on the hot-dip galvanizing, and the result of this salt spray test was not ideal.
(The white part of the surface is called white rust (zinc rust). The hot-dip galvanizing process uses zinc instead of iron to rust to prevent rust. It can also be said that zinc sacrifices itself to protect iron, which is the reason for white rust. , so white rust is not a basis for judging rust.)
We exposed the hot-dip galvanized sheet outdoors for 5 years, and the surface of the galvanized sheet did not produce red rust as in the above photos, indicating that zinc plays a role in protecting iron. (The outdoor exposure test is a test in which the test panel is placed outdoors and subjected to natural environments such as sunlight, wind and rain.)
Through the above experiments, we can see that the salt spray test results of the hot-dip galvanized sheet are not ideal, but the rust resistance performance in the general outdoor environment is good. In life, we can often see many buildings and facilities constructed of hot-dip galvanized parts (highway guardrails and signal light poles, etc.). Hot-dip galvanized parts have played a good anti-rust performance in practical applications and are widely used.
The results of the salt spray test are only one aspect of the anti-rust performance, but not all of the anti-rust performance. When we consider the rust protection performance of a coating, we need to look not only at the data of the salt spray test, but also with the results of other corrosion promotion tests.
For example, a person who runs 100 meters fast may not be good at baseball or football, but a person who runs fast may only have an advantage in baseball or football, so the running speed is only one of the physical fitness tests for sports such as football or baseball. indicators, but not all of them.
The same is true for the salt spray test. For details, please refer to the standard GB/T1771-2007.
Salt spray test results of Robalu paint
Finally, let's take a look at the results of the salt spray test of Robalu paint - no red rust after 1008 hours and in good condition.
The outdoor exposure test results were also good - no growth occurred after 5 years
Robalu paint has been exposed to the sun for 15 years without rusting.
