Graphite -> Glass (I)

Question 1

physical appearance of GRAPHITE

Answer 1

one of the two allotropes of carbon, it has a black to dark gray color with a dull sheen, can be mined in its natural form.

Question 2

microstructure of GRAPHITE

Answer 2

very strong crystalline layers stacked on top of each other with poor and weak bonds between these layers

Question 3

What everyday object uses GRAPHITE (where it is often referred to as lead)?

Answer 3

pencils

Question 4

metallic traits of GRAPHITE

Answer 4

can conduct electricity, ability to be machined (cut) using the same tools used for metals

Question 5

non-metallic trait of GRAPHITE

Answer 5

it does not melt under atmospheric pressure (makes it excellent for making crucibles or as casting molds for refractory metal alloys), high natural LUBRICITY (it is slippery)

Question 6

CERAMICS

Answer 6

consist of mineral-like ingredients, either as mixtures or in a pure form.

Question 7

PURE CERAMICS

Answer 7

created as lumps of raw product in a chemical plant

Question 8

COMMINUTION

Answer 8

process of crushing the lumps into powder in a BALL MILL.

Question 9

BALL MILL

Answer 9

a cylindrical drum that is lined with wear-resistant panels or bricks (Burrstone, Silica, or Alumina) and filled with ceramic balls (Zirconium Silicate). The lumps are turned into powder.

Question 10

What is mixed with the ceramic powder to create the desired thickness?

Answer 10

ceramic powder + water + binder(s)

Question 11

SLIP (in terms of ceramics)

Answer 11

larger amounts of water will create a runny and pourable consistency, allows the adoption of processes analogous to metal casting, but without the need for heat

Question 12

limiting the amount of water will produce a thick pliable plastic form suitable for…

Answer 12

MOLDING

Question 13

SLIP CASTING

Answer 13

same as SLUSH CASTING, but for ceramics instead of metals; slip is poured into a split mold and poured out when the desired thickness has solidified

Question 14

CERAMIC SPIN CASTING

Answer 14

similar to CENTRIFUGAL SPIN CASTING, but with ceramics instead of metals

Question 15

MOLDING

Answer 15

when shaping the pliable plastic MOLDING form of the moist ceramic blend, the methods are similar to FORGING and EXTRUSION of metals

Question 16

CERAMIC PRESSING

Answer 16

similar to CLOSED/IMPRESSIONS DIE FORGING

Question 17

CERAMIC EXTRUSION

Answer 17

pushes the material through the die cavity and the two die halves are brought together; a SCREW CONVEYER provides the driving force

Question 18

JIGGERING

Answer 18

the industrial equivalent of the manual potter’s wheel to mass produce circular forms; parts: plaster mold, clay slug, bat, bat former, jigger tool

Question 19

JIGGER TOOL

Answer 19

equivalent to potter’s hands; sweeps around the bat to create the final shape

Question 20

DRYING in terms of CERAMICS

Answer 20

the ceramic shape needs to be dried because any moisture can turn into steam and cause cracks in the FIRING STAGE

Question 21

GREENWARE

Answer 21

the resulting ceramic after the drying process, in a solid but fragile GREEN STATE, strong enough for light handling

Question 22

GREEN MACHINING

Answer 22

process of cutting GREENWARE

Question 23

KILN

Answer 23

a special oven that the final shape GREENWARE is placed into, the ceramic undergoes a chemical change that results in cross-linking and shrinking

Question 24

BISQUEWARE

Answer 24

the GREENWARE goes into the KILN and it is called BISQUEWARE when it comes out

Question 25

What are the advantages and disadvantages of BISQEWARE?

Answer 25

ADV- hard and durable DISADV- porous and susceptible to shattering from impacts or thermal shock

Question 26

HARD MACHINING

Answer 26

a technique used to machine BISQUEWARE

Question 27

DISADVANTAGE of HARD MACHINING

Answer 27

it requires abrasive cutting techniques; the ceramic is "notch sensitive" and care is needed to avoid sharp corners where cracks can start

Question 28

GLAZING

Answer 28

method of addressing the porosity of BISQUEWARE by applying a surface coating of runny SLIP

Question 29

GLAZEWARE

Answer 29

the coated BISQUEWARE is put in the KILN again and comes out as GLAZEWARE

Question 30

EXAMPLES of GLAZED products

Answer 30

most tableware ceramics, bathroom tiles, turbine blades

Question 31

GLASS

Answer 31

composed mostly of SILICA which exists in a crystalline form known as QUARTZ, and an amorphous state called FUSED SILICA

Question 32

FUSED SILICA

Answer 32

has a disorganized microstructure and possesses the transparent appearance of GLASS

Question 33

SODA LIME GLASS

Answer 33

contains sodium oxide (soda) and calcium oxide (lime)

Question 34

LEAD/FLINT GLASS

Answer 34

SILICA and LEAD OXIDE; known for its sparkle and clarity, while being able to block GAMMA and X-RAYS

Question 35

CROWN GLASS

Answer 35

POTASSIUM OXIDE creates this glass

Question 36

BOROSILICATE GLASS

Answer 36

BORON OXIDE results in this glass; known as PYREX, with superior thermal-shock resitance

Question 37

GORILLA GLASS

Answer 37

flexible corning glass widely used for smartphone and tablet screen protectors

Question 38

GLASS in the form of PLATE or SHEET

Answer 38

widely used in architectural applications, formed using rollers

Question 39

FLOAT GLASS

Answer 39

process of making very flat and smooth glass for window panes, the glass is supported by liquid tin during this process

Question 40

Why is LIQUID TIN used in the FLOAT GLASS process?

Answer 40

- non-toxic - more dense than glass - lower MP than glass temp - higher BP than glass temp - non-reactive with glass - non-wetting

Question 41

GLASS BLOWING

Answer 41

a GOB of molten glass is placed on the end of a long tube. a craftsman uses their lungs to force air into the center of the GOB, creating the glass container shape

Question 42

AUTOMATED GLASS BLOWING

Answer 42

the GOB is formed into a crude container called a PARISON using a pressing method. the PARISON is then transferred to a split mold of the final desired shape and reheated

Question 43

GLASS FIBER

Answer 43

long lengths of straight fiber with consistent diameters can be produced by BUSHING

Question 44

BUSHING

Answer 44

allowing molten glass to pour through a series of holes

Question 45

INSULATION BATTS

Answer 45

short curly fibers are preferred bc they don't pack together very well and leave a majority of airspace

Question 46

CELLULOSE

Answer 46

was used in attic insulation before GLASS FIBER BATTS, basically just old newspapers

Question 47

DISADVANTAGES of CELLULOSE

Answer 47

- burns - absorbs moisture - attracts critters - compacts over time - inferior R-value

Question 48

FLOOD LAMP - SCREW CONDUCTOR

Answer 48

brass sheet metal is generally used; it is BLANKED, DEEP DRAWN, and then BULGED

Question 49

FLOOD LAMP - LENS

Answer 49

the lens is PRESSED glass

Question 50

GLASS PRESSING

Answer 50

similar to ceramic pressing, but the glass GOB is pliable bc of heat instead of moisture

Question 51

FLOOD LAMP - REFLECTOR

Answer 51

needs to be reflective and PARABOLIC in shape; made with GLASS CENTRIFUGAL CASTING

Question 52

ADV of CENTRIFUGAL CASTING

Answer 52

any liquid placed into a container and spun will naturally form a parabolic shape

Question 53

The Achilles Heel of Graphite

Answer 53

Brittleness

Question 54

True/False: Graphite maintain its slipperiness in space?

Answer 54

True because it is not dependent on oxidation or external lubricants

Question 55

a specialized application for solid graphite in space vehicles.

Answer 55

docking latch bushings