CHAPTER
1
Introduction to
Materials Science
& Engineering
國立東華大學
材料科學與工程學系簡介
• 民國八十六年成立碩士班
– 八十九年大學部
– 九十一年博士班
• 目前有十五名專任教授
• 研究生八十餘名及大學生二百餘名
天生我材必有用
MSE 101: Introduction to Materials
Science & Engineering
Course Objective...
Introduce fundamental concepts in Materials
Science
You will learn about:
• material structure
• how structure dictates properties
• how processing can change structure
This course will help you to:
• use materials properly
• realize new design opportunities
with materials
3
COURSE MATERIALS (with WileyPLUS)
Required text:
• WileyPLUS for Materials Science and Engineering: An Introduction,
W.D. Callister, Jr. and D.G. Rethwisch, 9th edition, John Wiley
and Sons, Inc. (2014).
Website: https://www.wileyplus.com/WileyCDA/
•Homework assignments with instant feedback and hints
• Computer graded self-help problems
• Hotlinks in homework to supporting text section
• Quizzes
Online Open courses
https://www.edx.org/
https://www.coursera.org/
4
WEBSITES
Course Website:
• Syllabus
• Lecture notes
• Answer keys
• Grades
Text Website: http://www.wiley.com/college/callister
• VMSE for 3D visualization and manipulation of atomic structures
• Mechanical Engineering and Biomaterials online support modules
• Case studies of materials usage
• Extended learning objectives
• Self-assessment exercises
5
Virtual Materials Science & Engineering
(VMSE)
Website: Student Companion Site
• Users can manipulate molecules and crystals to
better visualize atomic structures
• Unit cells such as BCC, FCC, HCP
• Crystallographic planes, directions, and defects
• Polymer repeat units and molecules
• Diffusion computations
6
GRADING
Random in-lecture quizzes
Midterm #1
30%
Midterm #2
30%
Home work
20%
10%
Classroom performance 10%
7
Materials Science and Engineering
Content
魏茂國
 Historical perspective
 Materials science and engineering
 Why study materials science and engineering?
 Classification of materials
 Advanced materials
 Modern Materials needs
 Processing/structure/properties/performance
8
Materials Science and Engineering
Introduction
魏茂國
A familiar item that is fabricated
from three different material types
is the beverage container.
Beverages are marketed in
aluminum (metal) cans, glass
(ceramic) bottles, and plastic
(polymer) bottles.
Aluminum cans
(metal)
Glass bottles
(ceramic)
Plastic bottles
(polymer)
9
Chapter 1 - Introduction
• What is materials science?
• Why should we know about it?
• Materials drive our society
–
–
–
–
Stone Age (2.5 million BC)
Bronze Age (3500 BC)
Iron Age
(1000 BC)
Now?
• Silicon Age?
• Polymer Age?
• Carbon Age?
10
Materials Science and Engineering
Historical Perspective
魏茂國
 Materials are probably more deep-seated in our culture than most of us
realize.
Transportation, housing, clothing, communication, recreation, and food
production-virtually every segment of our everyday lives is influenced to
one degree or another by materials.
 Early civilizations have been designated by the level of their materials
development
(i.e., Stone Age, Bronze Age, Iron Age).
The earliest humans had access to only a very limited number of
materials, those that occur naturally: stone, wood, clay, skins, and so on.
11
Montage of Materials
What are Materials?
• the matter from which a thing is or can be made
• may be defined as substance of which something is
composed or made.
• We obtain materials from earth crust and atmosphere.
• Examples : Oxygen, Silicon, Alumium and Iron constitute 46.60,
27.72, 8.13 and 5.00 percentage of weight of earths
crust respectively.
 Nitrogen and Oxygen constitute 78.08 and 20.95
percentage of dry air by volume respectively.
1-2
Materials
• Tools, implements, articles, etc.
needed to make or do something
• Matter, Substance, Stuff, Fabric, …
• Have extension in space and time
• Inertia from their mass
• Exert gravitational attraction
• A specialized form of energy
300 => 400 ppm
Greenhouse gases: Water vapor (H2O), Carbon dioxide (CO2), Methane (CH4),
Nitrous oxide (N2O), Ozone (O3), CFCs
Materials Science and Engineering
Content
魏茂國
 Historical perspective
 Materials science and engineering
 Why study materials science and engineering?
 Classification of materials
 Advanced materials
 Modern Materials needs
 Processing/structure/properties/performance
16
Materials Science and Engineering
• Materials science deals with basic knowledge about the
internal structure, properties and processing of materials.
• Materials engineering deals with the application of
knowledge gained by materials science to convert materials
to products.
• Combined knowledge of materials enables engineers to
convert materials into the products needed by society.
Basic
Knowledge
of
Materials
Resultant
Knowledge
of Structure and
Properties
Materials Science
Materials Science and
Engineering
Materials knowledge spectrum.
Applied
Knowledge
of Materials
Materials Engineering
Inter-disciplinary or multi-disciplinary
材料科學與工程
• 研究製程、結構、性質及性能表現等
四者之間的關係
•
•
•
•
兼及理論與應用，橫跨工程與科學
具跨領域的整合性，在高科技產業中扮演關鍵的地位
是電子、資訊、通訊、航太、機械及光電產業的基礎
研究領域: 陶瓷材料 金屬材料 高分子材料 複合材料
半導體及電子材料 生物材料
• 材料為「工業之母」
Materials Science and Engineering
Materials Science
魏茂國
 Structure
- The structure of a material usually relates to the arrangement of its
internal components.
- Microscopic means that which is subject to direct observation using
some type of microscope.
- Structural elements that may be viewed with the naked eye are
termed macroscopic.
 Property
- A property is a material trait in terms of the kind and magnitude of
response to a specific imposed stimulus.
- Definitions of properties are made independent of material shape and
size. (not always true)
20
Six important properties in solid materials
• Mechanical properties
– relate deformation to an applied load or force.
• Electrical properties relate the stimulus to an electric field.
• Thermal properties: heat capacity, thermal conductivity.
• Magnetic properties
– demonstrate the response of a material to the application of a
magnetic field.
• Optical properties
– relate the stimulus is electromagnetic or light radiation.
• Deteriorative properties
– indicate the chemical reactivity of materials.
21
Materials Science & Engineering
• Study and establish the
interrelationship between processing,
structure, properties, and performance
– The structure will depend on how it is processed
– The properties will depend on its structure
– The performance will be a function of its properties.
22
Structure, Processing, & Properties
• Properties depend on structure
ex: hardness vs. structure of steel
(d)
Hardness (BHN)
6 00
5 00
4 00
(c)
(a)
(b)
4 mm
3 00
2 00
30 mm
30 mm
100
0.01 0.1
30 mm
1
10 100 1000
Cooling Rate (ºC/s)
• Processing can change structure
ex: structure vs cooling rate of steel
23
Optical properties vs. Structures
魏茂國
Materials Science and Engineering
 Transmittance of aluminum oxide
The structures of the three specimens are different in terms of crystal
boundaries and pores, which affect the optical transmittance properties.
- Single crystal (sapphire) (left): transparent.
- Polycrystal and fully dense (nonporous) (center): translucent.
- Polycrystal with 5% porosity (right): opaque.
24
Why study MSE?
• Be a material scientist and/or engineer
• All products involving materials
• Selection of right materials
– Ideal combination of properties – compromise
– Deterioration of materials
– Economics –cost
• Familiar with MSE
– Making judicious choice
– Creating or development new materials
25
Materials Science and Engineering
Content
魏茂國
 Historical perspective
 Materials science and engineering
 Why study materials science and engineering?
 Classification of materials
 Advanced materials
 Modern Materials needs
 Processing/structure/properties/performance
26
Classification of Materials
• Metals, Ceramics, Polymers, composites,
electronics, (Biomaterials)
• Element, compound, mixture, alloy
• By Form: powder, fiber, film, bulk
• By Phase: solid, liquid, gas, plasma (地水火風)
• By Crystallinity: crystalline, amorphous
• By Chemistry: Organic, Inorganic
• By property
– Electrical: conductor, insulator, semiconductor, superconductor
– Magnetic, optical, thermal, mechanical, sensor, catalysis
Periodic Table
http://www.chemicool.com/
http://www.chemicool.com/
29
Types of Materials
• Metals:
– Strong, ductile
– High thermal & electrical conductivity
– Opaque, reflective.
• Ceramics: ionic bonding (refractory) – compounds of metallic
& non-metallic elements (oxides, carbides, nitrides, sulfides)
– Brittle, glassy, elastic
– Non-conducting (insulators)
• Polymers/plastics: Covalent bonding  sharing of e’s
– Soft, ductile, low strength, low density
– Thermal & electrical insulators
– Optically translucent or transparent.
30
Classification of Materials
魏茂國
 Metals
- Metals are composed of one or more metallic elements, and often
nonmetallic elements in relatively small amounts.
- Atoms in metals and their alloys are arranged in a very ordered manner, and
relatively dense.
- They have large numbers of nonlocalized electrons; these electrons are not
bound to particular atoms.
- Properties: good conductors of electricity and heat, not transparent to light
- Quite strong, yet deformable, which accounts for their extensive use in
structural applications.
- Metals and alloys are commonly divided
into two classes.
1. Ferrous metals and alloys
2. Nonferrous metals and alloys
31
Classification of Materials
Materials Science and Engineering
魏茂國
 Ceramics
- Ceramics are compounds between metallic and nonmetallic elements.
They are most frequently oxides, nitrides, and carbides.
- Ceramics have exhibited extreme brittleness (lack of ductility) and are
highly susceptible to fracture.
- Ceramics are typically insulative to the passage of electricity and heat,
and are more resistant to high temperatures and harsh environments.
- Advantages for engineering applications
1. Light weight
2. High strength and hardness
3. Good heat and wear resistance
4. Reduced friction.
5. Insulative properties
32
Classification of Materials
魏茂國
 Polymers
- Polymers include the familiar plastic and rubber materials. They are
organic compounds that are chemically based on carbon, hydrogen, and
other nonmetallic elements.
- Have low densities and may be extremely ductile and pliable (i.e., plastic).
- Relatively inert chemically and unreactive in a large number of
environments.
- One major drawback to the polymers is their tendency to soften and/or
decompose at modest temperatures.
- They have low electrical conductivities and are
nonmagnetic.
Fig. 1.10 Several common objects that are made of
polymeric materials: plastic tableware, billiard balls,
a bicycle helmet, two dice, a lawn mower wheel, and
a plastic milk carton.
33
Room-temperature Density of various materials
fig_01_03
Stiffness value for various materials
fig_01_04
Strength values for various materials
fig_01_05
Fracture toughness for various materials
fig_01_06
Electrical conductivity for various materials
fig_01_07
The Materials Selection Process
1. Pick Application
Determine required Properties
Properties: mechanical, electrical, thermal,
magnetic, optical, deteriorative.
2. Properties
Identify candidate Material(s)
Material: structure, composition.
3. Material
Identify required Processing
Processing: changes structure and overall shape
ex: casting, sintering, vapor deposition, doping
forming, joining, annealing.
39
ELECTRICAL
• Electrical Resistivity of Copper:
6
(10-8 Ohm-m)
Resistivity, r
5
4
3
2
1
0
-200
-100
0
T (ºC)
• Adding “impurity” atoms to Cu increases resistivity.
• Deforming Cu increases resistivity.
40
• Space Shuttle Tiles:
THERMAL
-- It decreases when
you add zinc!
Thermal Conductivity
(W/m-K)
-- Silica fiber insulation
offers low heat conduction.
• Thermal Conductivity
of Copper:
100 mm
400
300
200
100
0
0
10
20 30 40
Composition (wt% Zinc)
41
MAGNETIC
• Magnetic Storage:
vs. Composition:
-- Adding 3 atomic % Si
makes Fe a better
recording medium!
Magnetization
-- Recording medium
is magnetized by
recording head.
• Magnetic Permeability
Fe+3%Si
Fe
Magnetic Field
Fig. 20.23, Callister & Rethwisch 8e.
42
DETERIORATIVE
-- causes cracks!
• Heat treatment: slows
crack speed in salt water!
crack speed (m/s)
• Stress & Saltwater...
10-8
10-10
“as-is”
“held at
160ºC for 1 hr
before testing”
Alloy 7178 tested in
saturated aqueous NaCl
solution at 23ºC
increasing load
-- material:
4 mm
7150-T651 Al "alloy"
(Zn,Cu,Mg,Zr)
43
Materials Science and Engineering
Content
魏茂國
 Historical perspective
 Materials science and engineering
 Why study materials science and engineering?
 Classification of materials
 Advanced materials
 Modern Materials needs
 Processing/structure/properties/performance
44
Future Trends
• Composite Materials
 Fiber reinforced plastics are primary products.
 On an average 3% annual growth from 1981 to 1987.
 Annual growth rate of 5% is predicted for new
composites such as Fiberglass-Epoxy and GraphiteEpoxy combinations.
 Commercial aircrafts are expected to use more and
more composite materials.
1-14
Future Trends
• Electronic Materials
 Use of electronic materials such as silicon
increased rapidly from 1970.
 Electronic materials are expected to play
vital role in “Factories of Future”.
 Use of computers and robots will increase
resulting in extensive growth in use of
electronic materials.
 Aluminum for interconnections in
integrated circuits might be replaced by
copper resulting in better conductivity.
1-15
Future Trends
• Smart Materials : Change their properties by sensing
external stimulus.
 Shape memory alloys: Strained material reverts back to
its original shape above a critical temperature.
 Used in heart valves and to expand arteries.
 Piezoelectric materials: Produce electric field when
exposed to force and vice versa.
 Used in actuators and vibration reducers.
MEMS and Nanomaterials
• MEMS: Microelectromechanical systems.
 Miniature devices
 Micro-pumps, sensors
• Nanomaterials: Characteristic length < 100 nm
 Examples: ceramics powder and grain size < 100 nm
 Nanomaterials are harder and stronger than bulk
materials.
 Have biocompatible characteristics ( as in Zirconia)
 Transistors and diodes are developed on a nanowire.
Competition of six major materials in USA
Case Study – Material Selection
• Problem: Select suitable material for bicycle frame
and fork.
Steel and
alloys
Wood
Low cost but
Heavy. Less
Corrosion
resistance
Light and
strong. But
Cannot be
shaped
Carbon fiber
Aluminum Ti and Mg
Reinforced
alloys
alloys
plastic
Very light and Light, moderately Slightly better
strong. No Strong. Corrosion
Than Al
corrosion.
Resistance. alloys. But much
Very expensive
expensive
expensive
Cost important? Select steel
Properties important? Select CFRP
Materials Science and Engineering
Content
魏茂國
 Historical perspective
 Materials science and engineering
 Why study materials science and engineering?
 Classification of materials
 Advanced materials
 Modern Materials needs
 Processing/structure/properties/performance
51
fig_01_11a
fig_01_11b
fig_01_11c
fig_01_11d
SUMMARY
Course Goals:
• Use the right material for the job.
• Understand the relation between properties,
structure, and processing.
• Recognize new design opportunities offered
by materials selection.
• Understand materials science and engineering.
56
Home Work #1
1. Write a short essay on “Why do you choose MSE as your
major?” and “What are the goals of your college education?”
2. Take a close look of your bicycle.
What are the major parts or components in the product?
What materials are used to make the components
in terms of elements and type of materials?
Why these materials are used?
(at least 500 words for each assignment)
57