Versatile Materials: Ceramics, Semiconductors, Polymers, and Composites

Vocabulary practice flashcards covering the properties and applications of ceramics, semiconductors, polymers, and composite materials from the lecture notes.

Ceramics

Materials made from dried clay or clay like mixtures, used as far back as the middle eastern city of dericho in $8000\,B.C.$

Traditional Ceramics

Ceramics made from easily obtainable raw materials including Clay, Silica (Sand), and feldspar (Crystalline rocks).

Modern Ceramics

Ceramics made from compounds of metallic and nonmetallic elements, such as Carbon, nitrogen, and Sulfar.

Firing

The heating process where ceramic shapes are heated to temperatures between $1000\,^{\circ}\text{C}$ and $1700\,^{\circ}\text{C}$.

Dehydration

The loss of water during the firing process which causes the spaces between particles to shrink.

Brittle

A property of some ceramics that causes them to break if dropped or if the temperature is changed quickly.

Chemical Resistance

The ability of ceramics to withstand oxygen, water, acids, bases, salts, and strong solvents.

Insulators

Materials that do not conduct heat or electricity, such as traditional ceramics used for wiring or Space Shuttle heat shields.

Chromium dioxide

An exception to traditional ceramic insulators that conducts electricity as well as most metals.

Semiconductors

Materials like metalloids Silicon $(Si)$ and germanium $(Ge)$ whose electrical conductivities can be controlled.

Doping

The process of adding impurities, such as arsenic $(As)$ or gallium $(Ga)$, to a semiconductor to modify its conductivity.

n-type Semiconductor

A semiconductor where the impurity (such as $Pb$ or $As$) causes the overall number of electrons to increase.

p-type Semiconductor

A semiconductor where doping (with elements like $B$ or $Ga$) reduces the overall number of electrons, creating holes or areas with fewer electrons.

Free electrons

Extra electrons in n-type semiconductors that are weakly attached to impurities and flow easily.

Transistors and Diodes

Devices made by placing n-type and p-type semiconductors together to control the flow of electrons in electrical circuits.

Polymers

Substances composed of molecules arranged in large chains of repeating units called monomers.

Synthetic

Materials that do not occur naturally but are manufactured in a laboratory or chemical plant.

Polypropylene

A polymer that can have $50,000$ to $200,000$ monomers in its chain.

Contact Cements

Synthetic adhesives used in the manufacture of automobile parts, furniture, leather goods, and decorative laminates.

Silicone

A structural adhesive used to seal windows and doors to prevent heat loss in buildings.

Ultraviolet-cured Adhesives

Adhesives used by orthodontists to bond braces brackets to teeth that set after exposure to ultraviolet light.

Composite

A mixture of two or more materials, where one is embedded or layered in another, to produce desired properties.

Fiberglass

A composite material made of small fibers of glass embedded in a Plastic, creating a strong and lightweight structure.

Graphite composites

Materials that are $13$ Percent lighter than aluminum, allowing the mass of an aircraft to be reduced by more than $2500\,kg$.