IC A Test 9 Pt 1 of 4

intergranular corrosion can stay undetected while weaking metal strength

electrochemical deterioration of a material or its properties due to chemical reaction w/ surrounding environment

Electrons may flow through liquid solutions only in the presence of ___.

a water solution with soluble salts makes corrosion of many alloys easy at ambient temperatures

The effect of different electrolyte concentrations create different electrical potentials across the surface.

Development of corrosion: 1) surface 2)penetration *3) if develops inside, creates holes on surface.

Which factor of corrosion? high temp or nightly drops in temp=high water vapor=high corrosive rate

Chemical reactions that occur at surfaces in contact with electrolytes

Most active metals are high on the list and corrode easily.

Which type of corrosion? Attack on grain boundaries and individual grains.

Which type of corrosion? extremely localized, holes of diff shapes, difficult to detect

The greater difference in galvanic activity, a slower rate of corrosion will occur.

10 factors influencing corrosion: The Hot Dads Sometimes Present Concern About Their Masculine Energy. (THDSPCATME)

Which factor of corrosion? as time passes metals naturally corrode. can decrease w/ product barriers or treatments.

Type Material, Heat, Dissimilar Mets, Surface Area, Presence Es, E Conct, Avail 02, Temp, Mech Stress, Exposure length

Which type of corrosion? Diff metals in contact w/ each other thru an electrolyte. Lower rate w/ gaskets & sealants.

Which form of corrosion causes aluminum to become white/gray powdery blotches?

All metals will corrode to some extent in a ___ environment.

Where are these metals with respect to the galvanic activity list? Stainless steel, nickel, copper, brass, chromium.

The effect of the type of material on corrosion is based on the likelihood metal will corrode based on its _____.

A(n) ______ will mask effects of corrosion and stop current between anodes & cathodes.

ions cannot move through ___ ___.

exfoliation can be prevented by separating aluminum and steel with a barrier like primer or sealant

Magnesium+Gold=fast rate corrosion & Aluminum+Cadmium=slow rate corrosion

Which factor of corrosion? Partially confined areas + reduced O2=adjacent metal to become anode w/ air-exposed metals.

Lithium, magnesium, aluminum, & zinc are examples of ____ metals. (high on list)

combination of 2+ metals

Which factor of corrosion? alloys susceptible to corrosion cracking. ex: machining, forming, welding, heat stress

Which factor of corrosion? Dirt, salt, acidic gases dissolve on wet surfaces. (high conductivity electrolytes=fast rate)

Cathodes have less tendency to corrode as a ___ ___.

Which factor of corrosion? 2 dissimilar metals make elect. contact w/ an electrolyte.

Which type of corrosion (most common)? Direct chem attack spreads uniformly on a surface, becomes thin & fails.

Dissimilar metals can be different metals, protected part of same metal, or a conductive non-metal.

Which factor of corrosion? Heavy sections of materials do not cool evenly, varied chem composition.

crevices usually found under bolt or rivet heads, at gasket surfaces and lap joints

the 4 conditions necessary for corrosion to occur

Which factor of corrosion? Size of anodes and cathodes.

Which factor of corrosion? Electrolytes on surface differ @ 1 location to another, corrosion occurs at different rates.

Which form of corrosion is characterized by rough, dulling, etching, or frosting?

Which type of corrosion? occur in crevice w/ stagnant pooled solutions, b/c local area diff from large environment

a water solution with soluble salts makes corrosion difficult at ambient temperatures

what is the smallest unit of an element (+ nucleus and - electrons)?

What is an example of an electrolyte?

one area of different electrolyte concentration

Anodes have a tendency to do what?

Silver, gold, palladum, titanium, & carbon are examples of ____ metals (low on list).

anode<cathode=fast rate, anode>cathode=slow rate

Which type of corrosion? advanced form of intergranular, lifted, swelling @ boundaries (on wrought/forged materials).

Which form of corrosion is characterized by a buildup of corrosion deposits at the joints?

An atom/group of molecules that has/have electric charge by gaining or losing electrons (+/-ions).

Uniform, Galvanic, Pitting, Intergranular, Exfoliation, Crevice (Ugly Guys Pee In Every Corner).

Current occurs when electrons are forced to move through ___ ___.

When metal corrodes, atoms lose ___ and become ___ charged.

iron combined with moisture & air will make iron return to its natural state, which is what?

What atomic particle has a negative charge?

Electrolytes are conductive liquids that must connect the ___& ___ to create _____.

corrosion occurs b/c of metals' tendency to return to what?

Noble metals corrode easily with dissimilar metals.