What is Corrosion ?

CORROSION SCIENCE

Toddy we learn about the corrosion science that is what is corrosion, how to corrosion process is occurring and how to prevent it. Let’s start learning, first of all we learn about what is corrosion.

Definition of Corrosion:

Corrosion is the presses of destruction or decomposition of metal by electrochemical and chemical attack of environment on the surface of metals called corrosion. The machines, equipment, various metallic structure and metallic parts damage due to corrosion. The corrosion of metals by a chemical attach due to environment is slow but rate of corrosion is fast due to formation of cell. During the formation of cell there are two types of cell is formed.

1) Electrochemical Cell

2) Electrolyte Cell

                                                                                                                        All about our solar system 

Types of Corrosion:

Direct Chemical Corrosion:
            The corrosion occurring due to direct attack of chemicals like atmospheric gases, hydrogen, oxygen, carbon dioxide, chlorine, nitrogen oxide etc and attack of hot flow liquids on the metals. The rate of this corrosion is depending upon the following factors.

• Temperature
• Moisture in Air 
• Nature of Oxide Film on Surface of Metal 
• Chemical Affinity between Metal and Gas

Electrochemical or Wet Corrosion:

 The corrosion of metal by the aqueous conduction medium with the formation of catholic and anodic areas is called electrochemical corrosion. The aqueous medium may be aqueous solution, see, water, moisture, and high humidity. In this corrosion anodic and catholic area  are form but corrosion occur only anodic aria and corrosion product is desolve into medium or deposited into surface of cathode.

This types of corrosion have two types.

1) Galvanic Corrosion

2) Concentration Cell Corrosion

1)   Galvani Corrosion:

Galvanic corrosion is electrochemical corrosion of a metal by attack of conducting medium, with the formation of galvanic cell is called galvanic corrosion.

2)   Concentration Cell Corrosion:

When a part of metal is contact with higher concentration of electrolyte and other part of metal is formed concentration cell .The part of metal which is contact with the low concentration of electrolyte act as anode and get corroded, this corrosion is called concentration cell corrosion. In easy word we say that "The concentration cell formed due to warring of Oxygen concentration on a metal, are called Concentration Cell Corrosion".