Unit 9 - oxidation and corrosion Flashcards

1
Q

characteristics of mild steel

A

excellent structural material as it is cheap easily formed and mechanically strong.
it rust at low temperature and oxidises at high temperatures.
FeO forms but it is not very protective

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2
Q

How to prevent corrosion

A

thicker material to allow for it
paints and coatings
corrosion inhibitors
cathodic protection

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3
Q

Explain Galvanic corrosion

A

it occurs when a potential difference is established between two electrically connected metals immersed in a corrosive or conductive solution

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4
Q

Prevention of galvanic corrosion

A

select metal alloys as close together as possible in the galvanic series
avoid unfavourable area effect of a small anode and large cathode
insulate dissimilar metals
apply coatings with caution
avoid threaded joints for materials far apart in the galvanic series

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5
Q

what is pitting

A

localised attack of a boldly exposed metallic surface where the rate of attack is greater in small areas than at others

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