WHAT IS CORROSION?
Corrosion is the natural deterioration of materials due to their interaction with the environment.
WHY DOES CORROSION OCCUR?
Corrosion occurs mainly in metals due to their reaction with oxygen.
In general, the processes can be chemical or electrochemical but they can also be physical or mechanical such as high salinity, high temperatures or industrial pollution.
CORROSION MECHANICAL PROCESSES
HIGH SALINITY
HIGH TEMPERATURES
INDUSTRIAL POLLUTION
We have all seen red rust on steel, green rust on copper and white rust on aluminium. This corrosion involves a large amount of money for all countries both to replace corroded structures and to maintain existing ones.
CORROSION ON METALS IMPLIES AN INCREASE IN COST IN TERMS OF REPLACEMENT OR MAINTENANCE OF PARTS OR TOOLS
There are basically four types of corrosion, but there are also others that occur to a lesser extent.
TYPES OF CORROSION IN METAL
The first would be general corrosion - corrosion develops evenly over the entire surface of the material. In this painting system, depending on the exposure time, less or more corrosion is produced.
GENERAL OR ATMOSPHERIC CORROSION.
Galvanic corrosion: it occurs when two different potential materials are in contact with an electrolyte. This type of corrosion is very dangerous because, under certain circumstances, the reaction rate can be very high.
GALVANIC CORROSION
Pitting corrosion: it is a localised attack on metals and is accelerated by the presence of chlorides. This type of corrosion is very dangerous because in the case of tanks containing liquids they can perforate.
PITTING CORROSION
Corrosion caused by turbulence: it occurs inside pipes due to the flow of liquids that successively remove the rust layers that are formed.
The UNE 12944 standard is used to determine corrosive environments and resistance of paint systems.
CORROSION CAUSED BY TURBULENCE.
27 авг 2024