Effective Process to avoid Environmental or Chemical Corrosion

Corrosion is the surface disintegration of metals/alloys within specific environment. Some metals basically exhibit high corrosion resistance than others and this can be attributed to several factors like their chemical constituents, the nature of electrochemical reactions itself and others. The corrosion resistance of metals can be defined in terms of its ability to withstand aggressive conditions. This determines to a large extent the operational lifetime of components in service. It is realized that the most widely used definition of corrosion is the degradation of material by its reaction with its environment. The fact that corrosion needs to be controlled cannot be overemphasized in view of the colossal amount of money that is expended on it annually. Materials are protected from corrosion through a wide variety of methods.

By retarding either the anodic or cathodic reactions the rate of corrosion can be reduced. This can be achieved in several ways: Conditioning the Metal or Conditioning the Corrosive Environment. Conditioning the Metal can be sub-divided into two main groups which is Coating the metal, in order to interpose a corrosion resistant coating between metal and environment or Alloying the Metal. Again the coating may consist of another metal, e.g. zinc or tin coatings on steel, a protective coating derived from the metal itself, e.g. aluminium oxide on "anodised" aluminium, organic coatings, such as resins, plastics, paints, enamel, oils and greases. The action of protective coatings is often more complex than simply providing a barrier between metal and environment. Paints may contain a corrosion inhibitor.

An industrial coating, paint or coating adopted by its protective, rather than its aesthetic properties, although it can provide both. Corrosion resistant coatings protect metal components against degradation due to moisture, salt spray, oxidation or exposure to a variety of environmental or industrial chemicals. A sharply chosen anti corrosion coating may provide an added protection to the metal surfaces and also work as a wall between the metal surface and corrosive materials or chemical compounds. Good quality Protective Coatings can make the life of the metal larger than its usual at corrosive or chemical environment.

Halar Coating is also one of the most successive processes of corrosion control. Halar is actually the brand name for ethylene chlorotrifluoroethylene, or ECTFE. The most basic explanation for Halar is that it is a type of plastic. This particular type of plastic known as Halar is special because it is semi-crystalline and melt-processable. Halar provides excellent chemical resistance and electrical insulating properties over a broad-use temperature range from cryogenic to 1500C. It is a tough material with excellent impact strength and is one of the best fluoropolymers for permeation resistance. Halar is particularly suitable for use as a coating material in protection and anti-corrosion applications thanks to its unique combination of properties like high impact strength, chemical and permeation resistance, flame resistance, dielectric properties, adhesion to substrate etc. Today Halar Coating is extensively utilized in chemical and pharmaceutical processes, semiconductor fabs, refineries, power plants as well as for many other different applications in contact with highly corrosive or ultra-pure chemicals, like strong inorganic bases and strong mineral and oxidizing acids.