Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

IE 301 > Exam 1 > Flashcards

Exam 1 Flashcards

1
Q

Investigate relationships between structures and properties of materials
Design/develop new materials

A

Materials science

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Create products from existing materials

Develop materials processing techniques

A

Materials engineering

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Processing affects _______ and ________ affects ________

A

Structure
Structure
Hardness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Properties of Metals?

A

Strong, ductile
High thermal & electrical conductivities
Opaque, reflective

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Properties of Polymers/plastics?

A

compounds of non-metallic elements
Soft, ductile, low strengths, low densities
Low thermal & electrical conductivities
Opaque, translucent or transparent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Properties of Ceramics?

A

compounds of metallic & non-metallic elements (oxides, carbides, nitrides, sulfides)
Hard, Brittle
Low thermal & electrical conductivities
Opaque, translucent, or transparent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Understand Material Selection Procedure

A

**Screenshot of slide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the six properties of materials?

A 
Mechanical 
Electrical 
Thermal 
Magnetic 
Optical 
Deteriorative
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Increasing ______ increases _____ of steel.

A

carbon content

hardness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What 3 things increase resistivity?

A

Increasing temperature
Increasing impurity content
Deformation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is Thermal Conductivity ?

A

measure of a material’s ability to conduct heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Increasing impurity content decreases _________.

A

Thermal conductivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Highly porous materials are _____ conductors of heat: therefore ceramics have _____ thermal conductivity

A

poor

ceramics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are two Magnetic properties?

A

Magnetic storage and magnetic permeability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The _________ of some materials depend on their structural characteristics

A

light transmittance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is an example of a deteriorative property?

A

stress-corrosion cracking

• For stress-corrosion cracking, rate of crack growth is diminished by heat treating

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Materials’ properties depend on their _______; ________ are determined by how materials are processed

A

structure(s)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

In terms of chemistry the three classifications of materials are

A

metals, ceramics, and polymers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

An important role of engineers is that of _________

A

materials selection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Organic compounds that are chemically based on carbon, hydrogen, and other nonmetallic elements low density and may be extremely flexible

A

Polymers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

combination of metallic elements (free electrons)
good conductors of electricity and heat
not transparent to visible light
strong and ductile

A

Metals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Compounds between metallic and nonmetallic elements, such as nitrides, oxides, carbides
insulators of electricity and heat
resistant to high temperature and harsh environment

A

Ceramics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Consisting of more than one material type, combination of the best characteristics of each of the component materials

A

Composities

ex. fiberglass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

the smallest particle of an element that possesses the physical and chemical properties of that element

A

atom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

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

A

atomic number

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

For an electrically neutral (equilibrium state) or complete atom: Atomic number =________

A

number of protons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Atomic mass =

A

mass of protons + mass of neutrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

the electrons that occupy the outermost filled shell

A

Valence electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Know atomic chem review

A

**lecture 2a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Smaller electronegativity is on the _____ side of the periodic table, while larger is on the _______

A

left

right

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

When is atomic bonding achieved?

A

when the atoms fill their outer s and p shells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the 3 types of atomic bonding?

A

Ionic Bonding
Covalent Bonding
Metallic Bonding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is a type of secondary bonding?

A

van der Waals (weak bonding)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is an ion?

A

an atom, or a molecule, in which the total number of electrons is not equal to the total number of protons, giving the atom or molecule a net positive or negative electrical charge.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What does ionic bonding occur between?

A

metallic and nonmetallic elements which are situated at the horizontal extremities of the periodic table

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What occurs during ionic bonding?

A

Metallic elements “transfer” valence electrons to nonmetallic atoms  They become ions
-all the atoms acquire stable or inert gas configurations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

The predominant bonding in _______ is ionic.

A

ceramics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Ionic materials are _____ and ______

A

hard

brittle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What occurs during covalent bonding?

A

Stable electron configurations are assumed by the “sharing” of electrons between adjacent atoms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

The predominant bonding in _______ is covalent.

A

polymers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Covalent bonds may be very ____, or may be very ____

A

strong

weak

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What occurs during metallic bonding?

A

The valence electrons are not bound to any particular atom in the solid and are free to drift throughout the entire metal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Characteristics & Caveats of metallic bonding?

A

Bonding may be strong or weak.
Good ductility
Good electrical conductivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Why are metallic materials usually good conductors?

A

Because their electrons are free to move in the sea of electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

weak electrostatic attractions between atomic or molecular dipoles

A

Van der Waals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

________ bonds can change dramatically the properties of certain materials.

A

Van der Waals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Melting Temperature (Tm) is ____ if the bond energy is _____

A

larger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Elastic Modulus E (measure of a material)

E is ______ if the bond energy is ______

A

larger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Know the summary of bonding slide

A

**screenshot of slide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What is the summary of the material selection process?

A

Application —> Require Properties —–> Candidate Materials ——> Processing Techniques —–> Structure —–> Property —–> Performance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

The properties of some materials are directly related to their __________

A

crystal structures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

How do atoms align themselves in a crystalline materials?

A

in a repetitive, precise 3-dimensional patterns over large atomic distances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Lattice

A

a three-dimensional array of points coinciding with atom positions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Unit cell

A

a smallest subdivision (repetitive) of crystalline lattice. Still retains overall characteristics of entire lattice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Hard sphere model

A

Atoms are thought of as being solid spheres having well-defined diameters; the spheres representing nearest-neighbor atoms touch one another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Face-Centered Cubic (FCC) Crystal Structure

A

A unit cell of cubic geometry with atoms located at each of the corners and the centers of all the cube faces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Number of Atoms in FCC Unit Cell

A

4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Body-Centered Cubic (BCC) Crystal Structure

A

A unit cell of cubic geometry with atoms located at all eight corners and a single atom at the cube center

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Number of Atoms in BCC Unit Cell

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What has important effect upon material properties?

A

Structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

some chemical elements to exist in two or more different forms, in the same physical state

A

Allotropic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

theoretical density of the material

A

Density of a unit cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Theoretical density is usually within ______ of the actual density of the pure material.

A

2 percent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Most efficient form of packing is the _________

A

close packed layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Less efficient is _______

A

square packing

66
Q

Materials that have _______ structures deform more easily than do body-centered cubic materials that are not ______

A

close packed

67
Q

Materials that are _______ tend to have higher strength values and are harder to deform than ________ materials

A

not close packed

close packed

68
Q

_______ materials have the most slip systems and thus are the easiest to deform without fracture

A

FCC - Face centered cubic

69
Q

For FCC, Close packed directions are ____ diagonals.

A

face

70
Q

For BCC, Close packed directions are ____ diagonals

A

cube

71
Q

Number of atoms/ unit cell in HCP

A

6

72
Q

Some materials have more than one crystal structure, depending on _______ & _______

A

temperature

pressure

73
Q

Allotropic Materials

A

materials that change crystal structure depending on temperature

74
Q

Upon completion of solidification, the colonies contact each other, forming ________

A

Grain boundaries

75
Q

Metals deform more easily in directions along which __________ on planes of atoms that are ________ together

A

atoms are in closest contact

most tightly packed

76
Q

Know how to find miller indices

A

**Screenshot of slide

77
Q

Mechanical properties

A

response of the material to an applied force or stress

78
Q

Important mechanical properties are

A

strength, ductility, stiffness, and hardness

79
Q

Three principal ways in which a load may be applied

A

Tension(tensile test)
Compression(compression test)
Shear (shear test)

80
Q

Lateral strains are _______ when the force is in tension

A

negative

81
Q

_____ is always dimensionless

A

Strain

82
Q

a linear portion on the stress-strain curve and the material will return to its original shape upon unloading

A

Elastic Region

83
Q

in elastic region, stress-strain are proportional to each other

A

Hooke’s law

84
Q

The ratio of the lateral and axial strains

A

Poisson’s Ratio

85
Q

Larger _______ minimize elastic deflection

A

elastic moduli

86
Q

What’s going on during elastic deformation?

A

Bond stretching during elastic deformation!

87
Q

Elastic means _________ and __________

A

Elastic

Nonpermanent

88
Q

modulus of elasticity is

A

a measure of stiffness of the material

89
Q

Plastic Behavior

A

As the material is deformed beyond the yield strength point, permanent, or plastic deformation occurs

90
Q

yield strength (proportional limit)

A

the initial departure from linearity of the stress-strain curve

91
Q

What’s going on during plastic deformation?

A

Dislocation is moving during plastic deformation

92
Q

Plastic deformation, or dislocation movement is __________

A

permanent

93
Q

Yield Strength

A

Stress at which noticeable plastic deformation has

occurred

94
Q

Tensile Strength

A

Maximum possible engineering stress in tension

95
Q

When does tensile strength for metals occur?

A

when noticeable necking starts

96
Q

Ductility

A

is the ability of a material to bend, stretch, or distort without breaking

97
Q

plastic tensile strain at fracture

A

Percent Elongation (%PE)

98
Q

A ductile material is ________

A

flexible

99
Q

Brittle materials:

%EL

A

< 5%

100
Q

Ductile materials:

%EL

A

> 5%

101
Q

Toughness

A

The ability of a material to absorb energy up to fracture

102
Q

For a material to be tough

it must display both _______ & _______

A

strength

ductility

103
Q

This reversible behavior often shows a linear relation between stress and strain

A

Elastic behavior

104
Q

This permanent deformation

A

Plastic behavior

105
Q

the slope of the elastic portion

A

Young’s modulus

106
Q

the stress at fracture

A

Fracture strength

107
Q

The total energy absorbed during plastic deformation…. to break the material

A

Toughness

108
Q

The plastic strain at failure

A

Ductility

109
Q

Hardness

A

A measurement of a material’s resistance to penetration or localized plastic deformation

110
Q

Steps in hardness test

A

A small indenter is forced into the surface of a material to be tested with certain load.
The depth / size of the resulting indentation is measured.
Such data are converted to a hardness number

111
Q

The softer the material, the ______ and ______ the indentation, and the _____ the hardness number

A

larger
deeper
lower

112
Q

What are hardness tests are performed more frequently than any other mechanical tests?

A

Simple / inexpensive
nondestructive
Other mechanical properties may be estimated from hardness data

113
Q

_________ is an accurate hardness measurement for soft materials

A

Brinell hardness (HB)

114
Q

________ is the most widely used of all metal hardness testing methods

A

Rockwell hardness (HR)

115
Q

_____ iron is much harder than the cast iron.

A

gray

116
Q

Atomic vibrations are in the form of _______ or _______

A

lattice waves

phonons

117
Q

Thermal Expansion (α )

A

Materials change size when temperature is changed

118
Q

Polymers have larger α values because of ___________

A

weak secondary bonds

119
Q

Thermal Conductivity

A

The ability of a material to transport heat.

120
Q

Atomic vibrations and free electrons in hotter regions transport energy to cooler regions.

A

Atomic perspective

121
Q

Why does thermal stress occur?

A

restrained thermal expansion/contraction

temperature gradients that lead to differential dimensional changes

122
Q

The thermal properties of materials include:

A

Coefficient of thermal expansion

Thermal conductivity

123
Q

Coefficient of thermal expansion

A

the size of a material changes with a change in temperature

polymers have the largest values

124
Q

Thermal conductivity

A

the ability of a material to transport heat

metals have the largest values

125
Q

Plastic deformation is __________ deformation.

A

permanent (non-recoverable)

126
Q

_________ and _________ are measures of a material’s resistance to plastic deformation

A

Strength

hardness

127
Q

During the plastic deformation, __________ must be ruptured and then reformed

A

interatomic bonds

128
Q

In crystalline solids, plastic deformation most often involves the ___________

A

motion of dislocations

129
Q

Edge Dislocation

A

associated with the edge of the extra half plane of atoms

130
Q

Breaking the bonds together to _________ requires extremely large stress

A

facilitate slip

131
Q

For metals, plastic deformation occurs by ______

A

slip – an edge dislocation slides over adjacent plane half-planes of atoms

132
Q

A dislocation moves along a _______ in a _________ perpendicular to the dislocation line

A

slip plane

slip direction

133
Q

The slip direction is the same as the ________ direction

A

Burgers vector

134
Q

Slip plane

A

plane on which easiest slippage occurs

Highest planar densities

135
Q

Slip directions

A
  • directions of movement

Highest linear densities

136
Q

BCC and FCC metals have a relatively ______ number of slip systems

A

large

Relatively ductile

137
Q

HCP metals having _____ active slip systems

A

few

Relatively brittle

138
Q

Dislocation Motion

A

Produces plastic deformation
Depends on incrementally breaking
bonds

139
Q

During plastic deformation, the number of dislocations ________ dramatically.

A

increases

140
Q

the separation of a body into two or more pieces in response to a static stress

A

simple fracture

141
Q

Two general types of fracture

A

ductile

brittle

142
Q

ductile

A

Slow crack propagation
Accompanied by significant plastic deformation
Fails with warning

143
Q

brittle

A

Rapid crack propagation
Little or no plastic deformation
Fails without warning

144
Q

______ fracture generally more desirable than _______ fracture

A

Ductile

Brittle

145
Q

cup-and-cone fracture

A

moderately ductile

146
Q

flat surfaces

A

brittle fracture

147
Q

one piece

large deformation

A

Ductile fracture

148
Q

many pieces

small deformations

A

Brittle fracture

149
Q

What are the stages of Stages of Moderately Ductile Failure?

A 
necking 
void nucleation
void growth and coalescence
crack propagation
fracture
150
Q

_____ fracture surface displays V-shaped, chevron markings

A

Brittle

151
Q

V features point to the

A

crack initiation site

152
Q

Transgranular crack propagation

A

through grains

153
Q

Intergranular crack propagation

A

between grains

154
Q

What are the Principles of Fracture Mechanics?

A

Fracture occurs as result of crack propagation

Measured fracture strengths of most materials much lower than predicted by theory

155
Q

Why are measured fracture strengths of most materials much lower than predicted by theory?

A 
microscopic flaws (cracks) always exist in materials
magnitude of applied tensile stress amplified at the tips of these cracks
156
Q

_____ are Stress Concentrators

A

flaws

157
Q

Stress concentration ______ for sharp cracks—propagate at _____ stresses than cracks with blunt tips

A

higher

lower

158
Q

Crack propagation for ductile materials ______

A

plastic deformation at crack tip when stress reaches yield strength—tip blunted—lowers stress conc.

159
Q

Measure of material’s resistance to brittle fracture when a crack is present

A

Fracture Toughness

160
Q

How to Reducing Stress Concentration ?

A

General Techniques

  1. Increase Fillet Radius (R)
  2. Reduce W/H ratio

IE 301 (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions