BASIC CORROSION
This is the gradual deterioration of a metal due to chemical or electrochemical reaction with the environment.
What is corrosion?
Corrosion occurring in the presence of moisture and electrolyte is called this.
What is wet corrosion?
Corrosion occurring when two dissimilar metals are connected in an electrolyte.
What is galvanic corrosion?
Chromium protects stainless steel by forming this thin protective layer.
What is a passive oxide film?
Coating iron with zinc to prevent corrosion is called this.
What is galvanization?
Rust on iron mainly consists of this hydrated compound.
What is hydrated ferric oxide?
Direct attack of oxygen on metals at high temperature is called this type of corrosion.
What is oxidation corrosion?
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In a zinc-copper couple, this metal corrodes first.
What is zinc?
This rule relates oxide volume to protective nature of oxide films.
What is the Pilling–Bedworth rule?
Magnesium blocks attached to pipelines act as these.
What are sacrificial anodes?
Corrosion causes loss of this important property used for electrical wiring.
What is electrical conductivity?
This type of oxide film protects the metal surface from further attack.
What is a non-porous oxide film?
Engineers use this practical series to predict corrosion behavior in seawater.
What is the galvanic series?
Oxide films containing cracks allow continued corrosion and are called this.
What are porous oxide films?
This method uses an external DC supply to prevent corrosion.
What is impressed current cathodic protection?
Metals naturally tend to return to this stable state found in nature.
What is the ore state (oxide/sulphide/carbonate form)?
Corrosion involving formation of electrochemical cells is known as this.
What is electrochemical corrosion?
A small anodic area connected to a large cathodic area causes this effect.
What is rapid corrosion of the anode?
Titanium and aluminum resist corrosion strongly because of this phenomenon.
What is passivation?
Paints and polymer layers belong to this type of corrosion protection.
What are protective coatings?
This branch of chemistry explains corrosion using oxidation and reduction reactions.
What is electrochemistry?
In wet corrosion, corrosion always occurs at this electrode region.
What is the anode?
Ship hull corrosion near the waterline commonly occurs due to this phenomenon.
What is differential aeration corrosion?
According to Pilling–Bedworth rule, oxide films with ratio less than one are generally this.
What are non-protective or porous films?
Graphite and high-silica iron are commonly used as these in cathodic protection systems.
What are insoluble anodes?