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Question 1

Galvanic corrosion

Answer 1

two metals dissimilar in anodic properties are put in a corrosive electrolyte

Question 2

Dealloying

Answer 2

the selective removal of one element from an alloy by corrosion processes

Question 3

Crevice corrosion

Answer 3

the attack of metal surfaces by a stagnant solution in crevices

Question 4

Pitting corrosion

Answer 4

local cathodic sites in a material are larger than the anodic sites

Question 5

Intergranular corrosion

Answer 5

preferential corrosion at grain boundaries

Question 6

Environmental sensitive fracture

Answer 6

worst kind, includes stress corrosion cracking, corrosion fatigue, hydrogen embrittlement

Question 7

Naturally “resistant” combinations

Answer 7

> nickel-caustic
lead-water
Al-atmosphere pressure

Question 8

Naturally “corrosive” combinations

Answer 8

> copper-ammonia
304SS-chlorides (sea water)
lead-wine

Question 9

What are the three kinds of corrosion?

Answer 9

> chemical: degradation of insulators
electrochemical: degradation of conductors and semiconductors in ionically conducting liquids
dry oxidation: degradation in reactive gases

Question 10

Substance producer, energy consumer

Answer 10

> electrodeposition

Question 11

Substance consumer, energy producer

Answer 11

> battery

> rechargeable when ions go back to initial state

Question 12

Energy and substance consumer

Answer 12

> corrosion

> short circuited battery