Aerosols are sea water droplets that are transported by […]
Aerosols are sea water droplets that are transported by the sea breeze from the ocean. During air travel, these droplets evaporate slightly, increasing their salt concentration, making them destructive. Once corrosion occurs, an effective technique now known as dry ice blasting can be used to eliminate flash rust that has formed.
In the external environment, stainless steel sometimes suffers from severe corrosion. However, as a rule, its performance rate is between excellent and excellent. This is especially true when using AISI 316; especially in the interior. The problem mainly occurs along the coastline, alongside the railway, and sometimes close to the harsh gas emissions from factories and vehicles. Another important factor is the condition of the surface of the material; the smoother the surface, the stronger the corrosion resistance of the material. This is also the reason why the ground stainless steel corrodes relatively quickly in the marine environment, while the polished surface remains in good condition. Figure 1 contains the corrosion of the grounded tube of the column and the polished cover looks dull.
The degree of corrosion resistance of stainless steel depends in part on the size of the gravel used. The finer the sand, the stronger the corrosion resistance. One disadvantage of grinding compared to pickling is that the grinding exposes small areas of poor corrosion resistance; these then serve as entry points for local attacks. If the sand used is too rough, dirt deposits can accumulate in the grooves, which can also cause corrosion; especially in seawater and chlorine-containing environments. The reason for this is that, with relatively large oxygen molecules, small chloride ions can penetrate deeper under dirt deposits. This is also known as "deposition corrosion." A clear example can be seen on passenger ships with highly polished AISI 316 railings. After the apparent sun's reflection caused too much trouble for the passengers, it was decided to replace the railings with ground K320 pipes made of AISI 316. Three months later, rusting plaques began to appear in several places on the pipe, causing shipping companies to think that AISI 304 was incorrectly provided instead of 316. After investigation, it was found that this was not the case; instead, it was the surface condition of the pipe that caused it. this phenomenon. There is no choice but to use a scouring pad to remove flash rust from the tube. The annoying part is that it must now be done on a regular basis, while the polished tube requires little maintenance.