915
Lectures Watched
Since January 1, 2014
Hundreds of free, self-paced university courses available:
my recommendations here
Peruse my collection of 275
influential people of the past.
View My Class Notes via:
Receive My Class Notes via E-Mail:

VIEW ARCHIVE


Contact Me via E-Mail:
edward [at] tanguay.info
Notes on video lecture:
The Six Categories of Engineering Materials
Choose from these words to fill the blanks below:
six, adjacent, sharing, control, luster, sheathing, plastic, submicroscopic, ionic, hydrogen, silicate, ductility, oxygen, Coulombic, light, conductivity, cations, spoken, engineering, ceramic, mobile
six categories of                        materials
nearly all materials used for modern applications come from these        categories
1. metals
metallic bond
                 atoms share electrons in a non-directional way
metal pan
can't see through it
electrons that provide the metallic bonding are reflecting any proton light rays from the environment
gives us the characteristic shiny             
can conduct electricity, since bonding electrons are             
power cord
metal is providing the                         
polymer                    that is providing the safety and insulation
2. polymers
covalent bond
directional bond
electron sharing between adjacent atoms
have a stable balance
               spatula
good structural integrity
convenient
          -weight
carbon-to-                 bonding
covalent
electrons are being shared by the two adjacent atoms
electrons are thus spoken for, good insulator
3. ceramics
           bond
non-directional bond
electron                from one atom to another
involves the electrostatic attraction between oppositely charged ions
atoms that have lost one or more electrons (known as               ) and atoms that have gained one or more electrons (known as anions)
from a metallic cation to a negative anion, very often             
                   forces
the magnitude of the electrostatic force of interaction between two point charges is directly proportional to the scalar multiplication of the magnitudes of charges and inversely proportional to the square of the distance between them
common ceramic coffee mug
electrons are              for, therefore electrical insulating
first three categories are based on the three different kind of electron bonding: metallic, covalent, and ionic
4. glass
a subset of ceramics
the key distinction between the                and glass
glass: random atomic arrangement of ions
ceramic: crystalline formation
common drinking glass
optically transparent
because of the nature of the ionic bonding
silicon ions and oxygen ions, a common                  material
5. fiberglass
best of both worlds
the                    of a polymer
ductility: when a solid material stretches under tensile stress
like the plastic spatula
harder structure
from microscopic glass fibers
a few microns in diameter
stacking chairs
fiberglass
6. semiconductors
small piece of silicon
microscopic and                             
can                the conductivity in a very powerful way

Spelling Corrections:

sillicatesilicate

Flashcards:

polymers have what kind of bond
covalent
ceramics have what kind of bond
ionic
glass is a subset of what
ceramics
what is the key distinction between the ceramic and glass
glass has random atomic arrangement, ceramic has crystalline formation
The Six Categories of Engineering Materials
Dislocations Explain Plastic Deformation