MODULE 1

Question 1

what are the four components of material science?

Answer 1

processing,structure,properties and performance

Question 2

Refers to the group of materials that are used in the construction of manmade structures and components.

Answer 2

Engineering materials

Question 3

What are the major classifications of engineering materials?

Answer 3

inclue metals,polymers, ceramics and composites.

Question 4

Materials are classified into two?

Answer 4

Metallic and Non-metallic

Question 5

involves investigating the relationships that exist between the structures and
properties of materials (i.e., why materials have their properties)

Answer 5

materials
science

Question 6

involves, on the basis of these structure–property correlations, designing or
engineering the structure of a material to produce a predetermined set of properties.

Answer 6

materials
engineering

Question 7

role of a material scientist

Answer 7

s to develop or synthesize
new materials

Question 8

role of a material engineer

Answer 8

is called upon to create new products or
systems using existing materials and/or to develop techniques for processing materials

Question 9

material usually relates to the arrangement of its internal components.

Answer 9

structure

Question 10

involves electrons within the individual atoms, their energies
and interactions with the nuclei

Answer 10

Subatomic structure

Question 11

involves electrons within the individual atoms, their energies
and interactions with the nuclei

Answer 11

Subatomic structure

Question 12

relates to the organization of atoms to yield molecules or crystals.

Answer 12

Atomic structure

Question 13

deals with aggregates of atoms that form particles (nanoparticles)
that have nanoscale dimensions (less that about 100 nm).

Answer 13

Nanostructure

Question 14

those structural elements that are subject to direct observation using
some type of microscope (structural features having dimensions between 100 nm
and several millimeters).

Answer 14

Microstructure

Question 15

structural elements that may be viewed with the naked eye (with
scale range between several millimeters and on the order of a meter).

Answer 15

Macrostructure

Question 16

a material trait in terms of the kind and magnitude of response to a
specific imposed stimulus

Answer 16

property

Question 17

relate deformation to an applied load or force; examples
include elastic modulus (stiffness), strength, and resistance to fracture.

Answer 17

Mechanical properties

Question 18

the stimulus is an applied electric fi eld; typical properties include electrical conductivity and dielectric constant.

Answer 18

Electrical properties

Question 19

are related to changes in temperature or temperature gradients
across a material; examples of thermal behavior include thermal expansion and heat
capacity.

Answer 19

Thermal properties

Question 20

the responses of a material to the application of a magnetic
fi eld; common magnetic properties include magnetic susceptibility and magnetization

Answer 20

Magnetic properties

Question 21

—the stimulus is electromagnetic or light radiation; index of refraction and refl ectivity are representative of _____

Answer 21

Optical properties

Question 22

relate to the chemical reactivity of materials; for
example, corrosion resistance of metals.

Answer 22

Deteriorative characteristics

Question 23

the structure of a material
depends on how it is???

Answer 23

processed

Question 24

a material’s performance is a function of??

Answer 24

properties

Question 25

means a model or set of ideas.)

Answer 25

“paradigm

Question 26

The four components of the discipline of materials science and engineering and their interrelationship

Answer 26

processing - structure - properties - performance

Question 27

Solid materials

Answer 27

metals, ceramics, and polymers

Question 28

are composed of one or more metallic elements (e.g., iron, aluminum, copper, titanium, gold, nickel), and often also nonmetallic elements (e.g., carbon, nitrogen, oxygen) in relatively small amounts.

Answer 28

Metals

Question 29

Atoms of metals?

Answer 29

arranged in avery orderly manner aand and are relatively dense in comparison to the ceramics and polymers

Question 30

mechanical characteristics of metals

Answer 30

these materials are relatively stiff and strong, yet are ductile (i.e., capable of large amounts of deformation without fracture), and are resistant to fracture

Question 31

Properties of metals

Answer 31

are extremely good conductors of electricity and heat 2. not transparent to visible light 3. a polished metal surface 4. has a lustrous appearance

Question 32

are compounds between metallic and nonmetallic elements; they are most frequently oxides, nitrides, and carbides

Answer 32

Ceramics

Question 33

mechanical behavior of ceramics?

Answer 33

are relatively stiff and strong—stiffnesses and strengths are comparable to those of the metals 2. they are typically very hard 3. extreme brittleness (lack of ductility) 4. highly susceptible to fracture

Question 34

Ceramic materials are typically?

Answer 34

insulative to the passage of heat and electricity (i.e., have low electrical conductivities, and are more resistant to high temperatures and harsh environments than are metals and polymers.

Question 35

include the familiar plastic and rubber materials. Many of them are organic compounds that are chemically based on carbon, hydrogen, and other nonmetallic elements (i.e., O, N, and Si)

Answer 35

Polymers

Question 36

Properties of polymers

Answer 36

1. low densities 2.their stiffnesses and strengths on a per-mass basis are comparable to those of the metals and ceramics 3. extremely ductile and pliable (i.e., plastic), which means they are easily formed into complex shapes. 4. e low electrical conductivities 5. nonmagnetic

Question 37

composed of two (or more) individual materials that come from the categories previously discussed—metals, ceramics, and polymers

Answer 37

composite

Question 39

include semiconductors, biomaterials, and what we may term materials of the future (i.e., smart materials and nanoengineered materials),

Answer 39

Advanced materials

Question 40

have electrical properties that are intermediate between those of electrical conductors (i.e., metals and metal alloys) and insulators (i.e., ceramics and polymers)

Answer 40

Semiconductors

Question 41

nonviable (i.e., nonliving) materials that are implanted into the body, so that they function in a reliable, safe, and physiologically satisfactory manner, while interacting with living tissue

Answer 41

biomaterial

Question 42

compatible with body tissues and fluids with which they are in contact over acceptable time periods.

Answer 42

biocompatible

Question 43

hey are not distinguished on the basis of their chemistry but rather their size; the nano prefix denotes that the dimensions of these structural entities are on the order of a nanometer (10−9 m)—as a rule, less than 100 nanometers (nm; equivalent to the diameter of approximately 500 atoms)

Answer 43

nanomaterials,

Question 44

Each chemical element is characterized by the number of protons in the nucleus, or the

Answer 44

atomic number

Question 45

of a specific atom may be expressed as the sum of the masses of protons and neutrons within the nucleus.

Answer 45

atomic mass

Question 46

atoms of some elements have two or more different atomic masses,

Answer 46

isotopes.

Question 47

corresponds to the weighted average of the atomic masses of the atom’s naturally occurring isotopes.

Answer 47

atomic weight

Question 48

may be used for computations of atomic weight.

Answer 48

atomic mass unit (amu)

Question 49

1 amu/atom (or molecule)

Answer 49

1 g/mol

Question 50

; protons and neutrons

Answer 50

1.67 × 10−27 kg

Question 51

electron

Answer 51

9.11 × 10−31 kg

Question 52

The mass number of the atom (M) is equal to

Answer 52

the sum of the number of protons and neutrons in the nucleus

Question 53

Bonding that is always found in compounds composed of both metallic and nonmetallic elements

Answer 53

Ionic bonding

Question 54

what is the direction of ionic bonding?

Answer 54

nondirectional

Question 55

magnitude of the bond is equal in all directions around an ion.

Answer 55

nondirectional

Question 56

What boonding has the lowest bonding energy?

Answer 56

van der Waals

Question 57

Bonding that happens between nonmetals?

Answer 57

Covalent bonding

Question 58

What happens in covalent bonding?

Answer 58

sharing of electrons

Question 59

What type of bond is there in covalent bonding?

Answer 59

Directional bond

Question 60

it is between specific atoms and may exist only in the direction between one atom and another that participates in the electron sharing.

Answer 60

directional

Question 61

Bonding found in metals and their alloys?

Answer 61

Metallic Bonding

Question 62

What type of bond is there in metaalic bonding?

Answer 62

Nondirectional

Question 63

It exists whenever there is some separation of positive and negative portions of an atom or molecule.

Answer 63

electric dipoles

Question 64

a special type of secondary bonding, is found to exist between some molecules that have hydrogen as one of the constituents.

Answer 64

Hydrogen bonding,

Question 65

3 Types of van der Waals bonds?

Answer 65

1. Fluctuating Induced Dipole Bonds 2. Polar Molecule-Induced Dipole Bonds 3. Permanent Dipole Bonds

Question 66

a special type of secondary bonding, is found to exist between some molecules that have hydrogen as one of the constituents.

Answer 66

Hydrogen Bonding

Question 67

Electric charge amount

Answer 67

1.60 x10 -19 C,

Question 68

using naturally occuring materials with only changes in shape I

Answer 68

Stone Age

Question 69

Ability to modify materials by refining (using heat), chemical modifications (alloying) and mechanical deformation (cold working)

Answer 69

Bronze Age

Question 70

Ability to heat treat at high temperature, control microstructure at different length scale and ability to design specific microstructures for specific properties

Answer 70

Iron Age

Question 71

Discovery of polymers, and the ability to synthesize and process polymers

Answer 71

Plastic Age

Question 72

Ability to control alloying accurately, ability to make thin films.

Answer 72

Silicon Age