Introduction

Question 1

What are the three types of materials

Answer 1

Metals, ceramics, polymers, and semiconductors

Question 2

What are the structures of materials in different scales

Answer 2

atomic, microscopic, macroscopic

Question 3

What are the different properties of materials

Answer 3

6: mechanical, thermal, electrical, optical, magnetic and deteriorative

Question 4

Whats material science vs engineering

Answer 4

science: studying structures and properties and their relation

engineering: designing structures with pre-determined properties

Question 5

Explain the subatomic level

Answer 5

electronic structure of each atom that defines the way they interact among other atoms

Question 6

Explain the atomic level

Answer 6

how atoms are arranged in materials (isotopes)

Question 7

Microscopic vs microscopic

Answer 7

micro: small
macro: naked eye

Question 8

metric system conversion

Answer 8

T G M k h da Base d c m u n p

Question 9

How much is an angstrom? What is it used to measure?

Answer 9

10^-10m
inter-atoms

Question 10

What prefix used to measure microelectronics? Quantum dot? cellular shit

Answer 10

micrometer, nanometer/micro, nanometer

Question 11

What are the different properties?

Answer 11

Mechanical, electrical, thermal, magnetic, optical, deteriorative/chemical

Question 12

Describe mechanical properties

Answer 12

Modulus (how elastic) , toughness, strength, hardness

Question 13

What is modulus

Answer 13

How elastic something is

Question 14

Describe electrical property

Answer 14

conductivity, resistivity, dielectric constant (amount of electric potential energy)

Question 15

Describe thermal property

Answer 15

heat capacity, thermal expansion, thermal conductivity

Question 16

Describe magnetic property

Answer 16

Diamagnetic: not attracted to external magnetic fields

paramagnetic: attracted to external magnetic fields

ferromagnetic: highly attracted to external magnetic fields

Question 17

Describe optical properties

Answer 17

reflectivity, absorption (opaque, translucent, transparent), transmission

Question 18

What is optical transmission

Answer 18

using light to travel through an optical fiber, converting it into electrical signals as the receiver (form of communication)

translucent, opaque, transparent

Question 19

Describe deteriorative and chemical properties

Answer 19

Oxidation, corrosion, irradiation (exposing to radiation)

Question 20

How do properties, structure and processing relate

Answer 20

properties depend on structure. Processing can change the structure

Question 21

electrical resistivity of copper with temperature and impurities

Answer 21

the more impurities, deforming and inc temperature, the more resistive it is

Question 22

what happens when you add zinc to copper

Answer 22

increases thermal conductivity

Question 23

What makes aluminum oxide different light transmissions

Answer 23

single crystals allows for light to be transparent high degree of perfection

lots of polycrystals low porosity: translucent; lots of small single crystals connected, boundaries scattering light from printed page

lots of polycrystals high porosity: opaque; lots of small interconnected cyrstals with pores that scatter light

Question 24

Describe metals

Answer 24

has valence electrons detached from atoms and spread in electron sea

Good conductors, of heat and electricity

tough, strong and deformable

Dense

Question 25

What’s ductile

Answer 25

deformable

Question 26

Describe semiconductors

Answer 26

The bonding is covalent.

semmi CONDUCTORS

sensitive to impurities

Question 27

Describe ceramics

Answer 27

either behave like positive or negative ions and bond by Coulomb forces.

Made of metals atoms and oxides, nitrides and carbides (CON)

Insulator of heat and electricity

Hard but brittle

Question 28

Describe polymers

Answer 28

large organic molecules based on carbon, hydrogen, other nonmetallic

Plastic, rubber,

soft, flexible, light

Question 29

Describe composites

Answer 29

Combination of metals, ceramics and polymers

Question 30

Describe fiberglass properties

Answer 30

flexible fiber, strong glass

Question 31

Material selection process

Answer 31

Choose what properties you want

Choose what materials have those properties

Choose the process your use to obrain a better product and to get shape

Question 32

What are the differnt processes of making a material

Answer 32

Casting, Sintering( to heat and compress without liquifying), vapor deposition, doping forming (adding impurities), annealing (heat treating to change physical and chemcal properties)

Question 33

Characteristics of nanostructured matierals

Answer 33

1 and 100 nm with unsusual properties

Like electronic components for quantum computing

Question 34

What’s special about shells and mollusces

Answer 34

shells are hard tissue, mollusks produce powerful adhesive

Question 35

cutting vs etching

Answer 35

cut, engraving

Question 36

Whats bottom up vs top bottom?

Answer 36

bottom up is building things from basic level since we have microscopes

Question 37

how bit are biomolecules and inorganic clusters?

Answer 37

5-15nm

Question 38

What are smart materials

Answer 38

have a sensor and an actuator (performs responsive and adaptive function like change shape, temp etc)

Question 39

Not important: what are the four types of materials used for actuators

Answer 39

shape-memory alloys (metals): change shape with temperature

piezoelectric ceramics: expand and contract with electric field (voltage)

magnetostrictive materials: analogous to piezoelectrics but respond to magnetic field

electorheological/magnetorheological fluids: different viscosity with application of electric and magnetic fields

Question 40

Whats an alloy

Answer 40

a combination of two or more elements (usually metals)