Navair 01-1A-509-1

Front 1

Corrosion

Back 1

______ is the electrochemical deterioration of a material or its properties due to its chemical reaction with the surrounding environment?

Front 2

ATOM

Back 2

The smallest unit of an element, made
up of a positively charged nucleus surrounded by a system of negatively charged electrons?

Front 3

Electron

Back 3

A negatively charged subatomic
particle?

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Ion

Back 4

An atom or group of atoms or molecules
which has acquired a net electric charge by gaining(negative ion) or losing (positive ion) electrons.

Front 5

Electrolyte

Back 5

A liquid (usually water) solution
containing ions. Sea water is an electrolyte: an aqueous(water-based) solution whose major components are
sodium and chloride ions.

Front 6

Grains

Back 6

Most alloys are made up entirely of small crystalline regions called?

Front 7

Dissimilar Metals

Back 7

What make electrical contact in the presence of an electrolyte, the rate at which corrosion occurs depends
on the difference in their activities, that is, their positions?

Front 8

(the anode), (the cathode)

Back 8

The rate of corrosion also depends on the size of the parts in contact. If the surface area of the corroding
metal______is smaller than the surface area of the less active metal ______, corrosion will be rapid and severe.

Front 9

Electrolyte

Back 9

Dirt, salt, acidic stack gases, and
engine exhaust gases can dissolve on wet surfaces,increasing the electrical conductivity of the ______,
thereby increasing the rate of corrosion.

Front 10

Concentration of the Electrolyte

Back 10

In the same way that metals can corrode when exposed to different concentrations of oxygen in an electrolyte, corrosion will also occur if the ______ on the surface varies from one location to another.

Front 11

an oxygen concentration cell or differential aeration cell

Back 11

When some of the electrolyte on a metal surface is partially confined (such)as between faying surfaces or in a deep crevice), metal in this confined area corrodes more rapidly than other metal surfaces of the same part outside this area. This type of corrosion is called?

Front 12

Temperature

Back 12

Higher _______ environments tend to produce more rapid corrosion due to accelerated chemical reactions and, in humid environments, higher concentration of water vapor in
the air.

Front 13

BIOLOGICAL ORGANISMS

Back 13

Bacterias, molds,fungi, and other living organisms (some microscopic)
can grow on damp surfaces.Once they are well established, the area tends to remain damp, increasing the possibility of corrosion.

Front 14

Stress Corrosion

Back 14

Many alloys used in aircraft construction are sensitive to a form of corrosion known as ______ cracking.

Front 15

Uniform Surface Corrosion

Back 15

______ is probably the most common type of corrosion. It results from a direct chemical attack on a metal surface that proceeds uniformly over the entire exposed surface

Front 16

Galvanic corrosion

Back 16

_______ occurs when different metals are in contact with each other and an electrolyte, such as sea water. It is usually recognizable by the presence of a buildup of corrosion deposits at the joint between the metals.

Front 17

Pitting corrosion

Back 17

______ is a form of extremely localized attack that results in holes in the metal.

Front 18

Intergranular corrosion

Back 18

______ is an attack on the grain
boundaries of the metal. A highly magnified cross section of any commercial alloy and granular structure of the metal.

Front 19

Exfoliation

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______ is an advanced form of intergranular corrosion where the surface grains of a metal are lifted up by the force of expanding corrosion
products occurring at the grain boundaries?

Front 20

Crevice corrosion

Back 20

______ is one of the most familiar types of corrosion. Field experience shows that this type of corrosion may occur in any crevice where a stagnant solution has pooled?

Front 21

Filiform corrosion

Back 21

______ is a form of crevice corrosion which occurs on metal surfaces having a thin (~4 mils) organic protective
coating. It is recognized by its characteristic worm like trace of corrosion products beneath the coating?

Front 22

Erosion corrosion

Back 22

_______ is the increase in the rate of attack on a metal due to the
action of a corrosive fluid against the metal surface. Generally the movement is rapid, and wear or abrasion occurs with the corrosion.
Characterized by grooves, gullies, waves, rounded holes and/or valleys in the metal surface?

Front 23

Stress corrosion

Back 23

______is the intergranular or transgranular cracking of a metal caused by the combined effects of
constant tensile stress (internal or applied) and corrosion. Internal or residual stresses may be produced by welding,cold working, forming, and heat treatment operations during the manufacture of a part?

Front 24

Corrosion fatigue

Back 24

_____is the cracking of metals caused by the combined effects of cyclic stress and corrosion. No metal is immune to reduction in its resistance to cyclic stress if the metal is in a corrosive environment?

Front 25

Fretting corrosion

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______occurs at contact areas between materials under load subject to repeated vibration. The relative motion needed to produce fretting is extremely small (sometimes as little as 10-8 cm?

Front 26

HOT CORROSION

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Also called high temperature oxidation. Corrosion in the absence of
water can occur at high temperatures? such as those found in turbine engine combustors, turbine sections,
and afterburners.

Front 27

Aluminum and aluminum alloys

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Are the most widely used materials for aircraft construction. In addition to its uses in aircraft? structure,

Front 28

Anodize

Back 28

Some aluminum parts are protected with an electrochemically applied
oxide coating called?

Front 29

Magnesium alloys

Back 29

Are the lightest structural metals used for aircraft and missile
airframes?

Front 30

Aluminum Alloy

Back 30

Surface pitting, intergranular, exfoliation, stress corrosion and fatigue cracking, and fretting. White to gray powder?

Front 31

Magnesium Alloy

Back 31

Highly susceptible to pitting White, powdery, snowlike mounds,and white spots on surface?

Front 32

Carbon & Low Alloy Steel(4000-8000 series)

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Surface oxidation and pitting;
surface and intergranular corrosion Reddish-brown oxide (rust).

Front 33

Stainless Steels
(300-400 series)

Back 33

Crevice corrosion; some pitting in marine environments; corrosion cracking; intergranular corrosion (300 series); surface corrosion (400
series)Rough surface; sometimes a red, brown, or black stain.

Front 34

Titanium Alloy

Back 34

Highly corrosion resistant; extended or repeated contact with chlorinated solvents may result in degradation of the metal's structural properties.
Cadmium plated tools can cause embrittlement. No visible corrosion products at low temperature. Colored surface oxides develop above
700° F (370° C).

Front 35

Cadmium (used as a protective plating
for steel)

Back 35

Uniform surface corrosion From white powdery deposit to brown or black
mottling of the surface.

Front 36

Chromium (plate)

Back 36

Pitting (promotes rusting of steel where pits occur in plate)No visible corrosion products; blistering of plating due to rusting and lifting.

Front 37

Nickel-base Alloy (Inconel, Monel)

Back 37

Generally has good corrosion resistant qualities; susceptible to pitting in sea water Green powdery deposit.

Front 38

Electroless Nickel(used as a plating)

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Pitting and flaking of surface plating
Nickel does not corrode, but promotes corrosion of aluminum base metal where pits occur in the plating.

Front 39

Copper-base Alloy,Brass, Bronze

Back 39

Surface and intergranular corrosion Blue or blue-green powdery deposit.

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Silver

Back 40

Will tarnish in presence of sulfur Brown to black film.

Front 41

Gold

Back 41

Highly corrosion resistant Deposits cause darkening of reflective surfaces.

Front 42

Tin

Back 42

Subject to whisker growth Whisker-like deposits.

Front 43

STEEL or Ferrous (iron) alloys

Back 43

are used to manufacture many aircraft components and massive structures and assemblies in aircraft ground support
equipment, such as missile gantries, silo crib structures, frames and bodies of trailers and vans, and lesser structural parts such as brackets, racks, and panels.

Front 44

Stainless steels, or corrosion resistant steels (as they are more properly described)

Back 44

are alloys of iron containing large amounts of chromium and nickel. Are used for gears, bearings, and high strength bolts, and for mountings, racks, brackets, and hardware in avionic systems.

Front 45

Acrylic

Back 45

UV light, moisture, solvents Discoloration, cracking.

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Adhesive

Back 46

Dirt, UV light, solvent, moisture Cracking, peeling.

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Ceramic

Back 47

Extreme heat Discoloration, cracking

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Cloth

Back 48

Dry rot, mildew Discoloration, tears, dust