Corrosion Questions

Question 1

What ways are there to protect metal from corrosion?

Answer 1

surface coating of paint

surface coating of metal ie. alclad

introduction of certain elements into the base metal

corrosion resistant alloy

surface coating of a chemical conversion coating
moisture barriers like lubricants and protectants

Question 2

Metal corrosion is the deterioration of the metal by 2 means. What are they?

Answer 2

Chemical
Electrochemical

Question 3

galvanic corrosion

Answer 3

dissimilar metal corrosion

Question 4

uniform surface

Answer 4

covering an entire surface general roughening

Question 5

filiform

Answer 5

worm like appearance caused by improper wash primer

Question 6

intergranular

Answer 6

attack along the grain boundaries from improper heat treating

Question 7

exfoliation

Answer 7

advanced form of intergranular with flaking

Question 8

stress

Answer 8

cracking from sustained tensile force and corrosive environment

Question 9

fretting

Answer 9

matting surfaces have slight relative motion between them leaving fine debris

Question 10

a smoking rivet is a sign of

Answer 10

fretting

Question 11

oxidation

Answer 11

when metal is exposed to oxygen in the air

Question 12

concentration cell

Answer 12

has 2 forms; oxygen and metallic ion

Question 13

pitting

Answer 13

pockets of white or gray powder

Question 14

There are two general classifications of corrosion.

Answer 14

direct chemical and spilled battery acid is an example of it.

direct chemical and electroplating is an example of it.

Question 15

_____ ______ and _______ _______ ____ is an example of it.

Answer 15

direct chemical

spilled battery acid

Question 16

What is needed for electrochemical attack to occur (3)

Answer 16

anode
cathode
electrolyte

Question 17

Heat will speed up corrosion

Answer 17

True

Question 18

Water is worse than salt water for corrosion

Answer 18

False

Question 19

Florida weather is worse than Oklahoma

Answer 19

True

Question 20

Soil and dust do not affect corrosion

Answer 20

False

Question 21

Exhaust residue harms the paint but not corrosive

Answer 21

False

Question 22

Welding flux is corrosive

Answer 22

True

Question 23

Corrosion preventive maintenance includes the following: (9)

Answer 23

sealing against water

treatment of corrosion and touchup of paint

adequate cleaning

use of protective covers

periodic lubrication

wipe down of exposed critical areas

detailed inspection

clearing drain holes

draining of fuel cell sumps

Question 24

What are some corrosion prone areas (7)

Answer 24

exhaust trail areas

bilge area

flap recesses

piano hinge

lavs and galleys

wheel well

battery compartment and vent openings

Question 25

5 steps to corrosion removal

Answer 25

cleaning and stripping of the corroded area

restore protective surface

apply temporary or permanent coatings or paint finishes

removing as much of the corrosion as practicable

neutralizing residue

Question 26

Ways to prevent dissimilar metal corrosion (involving contact) (5)

Answer 26

washers

grease

metal primer

sealant

aluminum tape