AMPP CIP Level 1 Theory
What is corrosion? - answer The deterioration of a metal or alloy that results from an
electrochemical reaction with its environment.
What needs to be present in order for corrosion to occur? - answer Anode
Cathode
Metallic Pathway
Electrolyte
What is an anode? - answer The anode is the area of the metal surface that
corrodes. The metal oxidizes (gains oxygen), causing it to lose mass and dissolve into
the electrolyte.
What is oxidation? - answer Oxidation is a chemical reaction that occurs at the
anode where the metal loses electrons.
What is a cathode? - answer The cathode is the area of the metal surface that
reduces (loses oxygen).
What is reduction? - answer Reduction is a chemical reaction that occurs at the
cathode that involves the metal gaining electrons.
What is the metallic pathway? - answer The metallic pathway connects the anode to
the cathode and allows the passage of electrons generated from the cathode to the
anode.
What is an electrolyte? - answer The electrolyte is the conductive medium (any
solution, like water) in which ions are carried from the anode to the cathode.
What is a barrier coating? - answer A barrier coating protects the substrate/metal by
providing a chemical and physical barrier between the metal surface and the
environment.
The barrier coating interrupts the electrolyte of the electrochemical cell.
What is passivation? - answer Passivation is when a layer of oxides form on the
surface of a metal that provides corrosion protection.
, What is the purpose of the electrolyte? - answer To allow the passage of ions from
the anode to the cathode.
What is a sacrificial coating? - answer A sacrificial coating is a coating that contains
a metal (usually zinc) that will corrode instead of the metal substrate.
What is an inhibitive coating? - answer Inhibitive coatings act as aa barricade to slow
down the reaction at the anode, or cathode, or both. They contain special pigments that
react with moisture or oxygen and form a hard, non-reactive surface film that interferes
with the corrosion process.
What are the 4 basic components of a coating? - answer Pigments
Binder/Resins
Solvents
Additives
What is are pigments? - answer Pigments are the solid particles that give specific
protective, mechanical, or decorative qualities to the coating.
In its unmixed form, pigments are powders.
What are binders/resins? - answer Binders/resins are liquids that adhere to the
substrate and chemically change (cure) to form a hard, protective film.
What are solvents? - answer Solvents are the liquid components of the coating that
are responsible for dissolving the solid binder/resin.
What are additives? - answer Additives are special ingredients used to enhance the
performance or certain properties or characteristics of coatings.
They are commonly liquid components that are added in small amounts.
Which 3 materials are commonly used as galvanic anodes for carbon steel? - answer
Zinc
Magnesium
Aluminum
How does high or low temperature affect the corrosion rate? - answer High temp =
corrosion rate increases
Low temp = corrosion rate decreases
What is the primary role of a coating inspector? - answer To ensure compliance with
the contract/project specifications.
What is corrosion? - answer The deterioration of a metal or alloy that results from an
electrochemical reaction with its environment.
What needs to be present in order for corrosion to occur? - answer Anode
Cathode
Metallic Pathway
Electrolyte
What is an anode? - answer The anode is the area of the metal surface that
corrodes. The metal oxidizes (gains oxygen), causing it to lose mass and dissolve into
the electrolyte.
What is oxidation? - answer Oxidation is a chemical reaction that occurs at the
anode where the metal loses electrons.
What is a cathode? - answer The cathode is the area of the metal surface that
reduces (loses oxygen).
What is reduction? - answer Reduction is a chemical reaction that occurs at the
cathode that involves the metal gaining electrons.
What is the metallic pathway? - answer The metallic pathway connects the anode to
the cathode and allows the passage of electrons generated from the cathode to the
anode.
What is an electrolyte? - answer The electrolyte is the conductive medium (any
solution, like water) in which ions are carried from the anode to the cathode.
What is a barrier coating? - answer A barrier coating protects the substrate/metal by
providing a chemical and physical barrier between the metal surface and the
environment.
The barrier coating interrupts the electrolyte of the electrochemical cell.
What is passivation? - answer Passivation is when a layer of oxides form on the
surface of a metal that provides corrosion protection.
, What is the purpose of the electrolyte? - answer To allow the passage of ions from
the anode to the cathode.
What is a sacrificial coating? - answer A sacrificial coating is a coating that contains
a metal (usually zinc) that will corrode instead of the metal substrate.
What is an inhibitive coating? - answer Inhibitive coatings act as aa barricade to slow
down the reaction at the anode, or cathode, or both. They contain special pigments that
react with moisture or oxygen and form a hard, non-reactive surface film that interferes
with the corrosion process.
What are the 4 basic components of a coating? - answer Pigments
Binder/Resins
Solvents
Additives
What is are pigments? - answer Pigments are the solid particles that give specific
protective, mechanical, or decorative qualities to the coating.
In its unmixed form, pigments are powders.
What are binders/resins? - answer Binders/resins are liquids that adhere to the
substrate and chemically change (cure) to form a hard, protective film.
What are solvents? - answer Solvents are the liquid components of the coating that
are responsible for dissolving the solid binder/resin.
What are additives? - answer Additives are special ingredients used to enhance the
performance or certain properties or characteristics of coatings.
They are commonly liquid components that are added in small amounts.
Which 3 materials are commonly used as galvanic anodes for carbon steel? - answer
Zinc
Magnesium
Aluminum
How does high or low temperature affect the corrosion rate? - answer High temp =
corrosion rate increases
Low temp = corrosion rate decreases
What is the primary role of a coating inspector? - answer To ensure compliance with
the contract/project specifications.
