exam 3 Flashcards
Anion –
Atom in a molecule that gains an electron through bonding
Cation –
Atom in a molecule that loses an electron through bonding
Frenkel Defect –
A cation vacancy paired with a cation interstitial (could also describe
anion, but it is rarer for anions)
Schottky Defect –
A cation vacancy paired with an anion vacancy
Stoichiometry –
Describes the ratio of anions to cations in a crystal structure
Viscosity –
Measure of a glassy material’s resistance to deformation
Polymer –
Large chain of repeating units with same chemical makeup
Mer –
Single unit of polymer
Monomer –
A mer that exists on its own
Isomer –
A molecule with the same chemical formula but different arrangement
Copolymer –
Polymer with more than one type of mer
Thermoplastic –
Polymer can break apart during heating
Thermosetting –
Polymer is permanently set upon cooldown
Elastomer –
Totally elastic type of polymer
Particle Reinforced –
Large particles in a matrix
Fiber Reinforced –
Long fibers in a matrix
Cement –
Ceramic that mixes with water then hardens
Concrete –
Composite made with cement, sand, gravel, water
Oxidation –
Element gives up electron
Reduction –
Element gains electron
Anode –
Metal where oxidation occurs
Cathode –
Metal where reduction occurs
Uniform –
All corrosion happens equally across the entire surface
Galvanic –
Two different metals are exposed to an electrolyte (think salt water), and
electrons travel from one metal, through the electrolyte, to the other metal
Crevice –
corrosion is local to a crevice between two faces
Pitting –
Similar to crevice corrosion, caused by defects in the material
Intergranular –
Corrosion happens along grain boundaries
Selective Leaching –
One metal in an alloy corrodes faster than the other
Erosion –
Fluid with ions continuously flows over a surface, as electrons are stolen, and
ions become neutral, new ions replace them with flow
Stress corrosion –
the combination of the two causes failure quicker
Hydrogen embrittlement (not technically corrosion) –
hydrogen ions insert themselves in
the material structure, which weakens it
Conductor –
Material that easily conducts electricity
Insulator –
Material that resists electric current
Electron drift velocity –
How quickly an electron moves through an electric field
Band gap –
Range of energy values an electron cannot possess
Intrinsic semiconductor –
No intentional impurities, high resistivity
Extrinsic semiconductor –
Intentional impurities change the material’s ability to conduct
electricity
N-type –
Impurities that produce extra electrons
P-type –
Impurities that produce extra holes for electrons
Capacitance –
Ability to store electric charge across a distance
Piezoelectricity –
External force on a ceramic creates electric field
Heat capacity –
Ratio of energy added to material to change in temperature
Phonon –
A way to describe the wave of atomic displacement due to vibrations
Thermal conductivity –
Rate at which heat passes through a distance
Thermal expansion –
Volume of a material increases with temperature
Thermal stresses/shock –
Expansion due to temperature causes stress on a restrained
material
Diamagnetic –
Magnetism that only exists when an external field is applied
Ferrimagnetic –
Ceramics that have permanent magnetization
Ferromagnetic –
Permanent magnetic moment without external force
Magnetic Moment –
Moment that occurs due to motion of electrons
Paramagnetic –
Exists due to permanent dipoles
Absorption –
Energy from a photon is absorbed by an electron
Color –
Wavelength of light emitted from an electron moving to a lower energy state
Reflection –
Light is reflected at the surface
Refraction –
Transmitted light experiences change in velocity and is bent
Transmission –
Light passes through a solid
