Theory of Failure (Corrosion)

Corrosion: A metal (a)   process resulted from interaction with its environment.

Which is the correct changes in metal's characteristic due to corrosion?

• Increasing its heat transfer rate

• thickening of metal

• Leak, sudden failure/damage of equipment

• shiny appearance

Below are the corrosion agent to metal, except?

• Water

• Oxygen

• Fire

• Salts

What is the correct pair of important process in corrosion?

• Anode - reduction

• Electrolyte - any solution that contains ion

• Cathode - oxidation

• Reduction - cathode

• Oxidation - cathode

• Reduction - anode

• Oxidation - anode

Choose the correct pair.

• a) Strong oxidizing agents/more cathodic

  b) Strong reducing agents/more anodic

• a) Strong oxidizing agents/more anodic

  b) Strong reducing agents/more cathodic

• a) Strong reducing agents/more cathodic

  b) Strong oxidizing agents/more anodic

• a) Strong reducing agents/more anodic

  b) Strong oxidizing agents/more cathodic

Which form of corrosion match with description below:

" Downward propagation of small pits & holes"

• Crevice

• Galvanic

• Pitting

• Intergranular

Which form of corrosion match with the description below:

" between two pieces of the same metal"

• Crevice

• Uniform attack

• Stress corrosion

• Erosion-corrosion

Choose the correct form of corrosion based on schematic diagram given.

• Pitting

• Intergranular

• Crevice

• Galvanic