Rupert

1. Chapter 1 -
MENG286: INTRODUCTION TO
MATERIALS SCIENCE &
ENGINEERING

2. Chapter 1 -
2
COURSEMATERIALS
Required text:
•Materials Science and Engineering: An Introduction,
W.D. Callister, Jr. and D.G. Rethwisch, 8th edition, John
Wiley and Sons, Inc. (2010).

3. Chapter 1 -
3
GRADING
Biweekly quizzes: 20%
• Held at the beginning of tutorial hours
• Based on core textbook problems
Laboratory reports :30%
Four laboratory reports
Midterm: 20%
Final :30%
Attends : <%50=NG.
Filed to submit the lab or never attend lab
hours=NG.

4. Chapter 1 - 4
Chapter 1 - Introduction
• What is materials science?
• Why should we know about it?
• Materials drive our society
– Stone Age
– Bronze Age
– Iron Age
– Now?
• Silicon Age?
• Polymer Age?

5. Chapter 1 -
WHY STUDY MATERIALS SCI. &
ENG.?
5
• To be able to select a material for a given use based
on considerations of cost and performance.
• To understand the limits of materials and the change
of their properties with use.
• To be able to create a new material that will have
some desirable properties.

6. Chapter 1 -
MATERIALS SICENCE VS MATERIALS
ENG.
6
On the basis of structure-property correlations:
•Materials science involves investigating the
relationship btw structures & properties of materials.
•Materials Eng. is designing or engineering the
structure of a material to produce a predetermined set
of properties.

7. Chapter 1 -
MATERIALS SICENCE VS MATERIALS
ENG.
7
On the basis of functional prospective:
•The role of materials scientist is to develop or
synthesize new materials
•Materials Eng. is called upon to create new products
or systems using existing materials, and/or develop
techniques for processing materials.

8. Chapter 1 -
TYPESOFMATERIALS
8
Most engineering materials can be classified into one of
three basic categories:
1. Metals
2. Ceramics
3. Polymers
Their chemistries are different, and their mechanical and
physical properties are different
In addition, there is a fourth category:
4. Composites
-is a nonhomogeneous mixture of the other three types, rather than
a unique category

9. Chapter 1 -
1
1
Source: Fundamentals of Modern
Manufacturing materials: processes and
systems, M.P. Groover, 5th edition, John
Wiley & Sons Inc. (2007).
TYPESOF MATERIALS (con’t)

10. Chapter 1 -
METALS
Fig 1.8 Familiar objects that are made of metals and metal alloys
Metallic bonds
– Strong, ductile, resistant to fracture
– High thermal & electrical conductivity
– Opaque, reflective.

11. Chapter 1 -
CERAMICS
13
Fig 1.8 Familiar objects that are made of ceramic materials
Ionic bonding
–Brittle, glassy, elastic
–Non-conducting (insulative to the passage of heat & electricity)
–Transparent, translucent, or opaque
–Some exhibit magnetic behavior (e.g. Fe3O4)

12. Chapter 1 -
POLYMERS/PLASTICS
Fig 1.8 Familiar objects that are made of polymeric materials
Covalent bonding  sharing of e’s
–Soft, ductile, low strength, low density
–Thermal & electrical insulators
–Optically translucent or transparent.
–Chemically inert and unreactive
–Sensitive to temperature changes

13. Chapter 1 -
COMPOSITES
13
– Light, strong, flexible
– High costs

14. Chapter 1 -
ADVANCEDMATERIALS
14
Materials that are utilized in high-tech applications
•Semiconductors
Have electrical conductivities intermediate between conductors
and insulators
•Biomaterials
Must be compatible with body tissues
•Smart materials
Could sense and respond to changes in their environments in
predetermined manners
•Nanomaterials
Have structural features on the order of a nanometer, some of
which may be designed on the atomic/molecular level

15. Chapter 1 -
Example– HIP IMPLANT
15
• Requirements
– mechanical strength
(many cycles)
– good lubricity
– biocompatibility
Adapted from Fig. 22.26, Callister 7e.

16. Chapter 1 -
Typesof Materials(Con’t)
16
Fig 1.3 Bar chart of room-temperature density values for various metals, ceramics, polymers, and
composite materials

17. Chapter 1 -
Typesof Materials(Con’t)
17
Fig 1.4 Bar chart of room-temperature stiffness values for various metals, ceramics, polymers, and
composite materials

18. Chapter 1 -
Typesof Materials(Con’t)
Fig 1.5 Bar chart of room-temperature strength (i.e. tensile strength) values for various metals,
ceramics, polymers, and composite materials

19. Chapter 1 -
Typesof Materials(Con’t)
Fig 1.6 Bar chart of room-temperature resistance to fracture for various metals, ceramics, polymers,
and composite materials

20. Chapter 1 - 20
1. Pick Application Determine required Properties
Processing: changes structure and overall shape
ex: casting, sintering, vapor deposition, doping
forming, joining, annealing.
Properties: mechanical, electrical, thermal,
magnetic, optical, deteriorative.
Material: structure, composition.
2. Properties Identify candidate Material(s)
3. Material Identify required Processing
The Materials Selection Process

21. Chapter 1 -
22
STRUCTURE,PROCESSING, &
PROPERTIES
• One aspect of Materials Science is the investigation
of relationships that exist between the processing,
structures, properties, and performance of
materials.
• The performance of a material depends on its
properties
• Properties depend on structure ex: hardness vs
structure of steel
• Processing can change structure
Ex: structure vs cooling rate of steel
Fig 1.1 The four components of the discipline of materials science and engineering and their
interrelationship

22. Chapter 1 - 22
• Transmittance:
-- Aluminum oxide may be transparent, translucent, or
opaque depending on the material’s structure (i.e.,
single crystal vs. polycrystal, and degree of porosity).
Fig. 1.2, Callister &
Rethwisch 9e.
(Specimen preparation,
P.A. Lessing)
single crystal
polycrystal:
no porosity
polycrystal:
some porosity

23. Chapter 1 -
23
STRUCTUREOFMATERIALS
• By structure we mean how some internal
components of the material is (are)
arranged.
• In terms of dimensionality, structural
elements include subatomic, atomic,
microscopic, and macroscopic

24. Chapter 1 - 24
ex: hardness vs structure of steel
• Properties depend on structure
Data obtained from Figs. 12.31(a) and
12.32 with 4 wt% C composition, and from
Fig. 17.8, Callister & Rethwisch 9e.
Micrographs adapted from (a) Fig. 12.19;
(b) Fig. 11.29; (c) Fig. 12.33; and (d) Fig.
12.21, Callister & Rethwisch 9e. (Figures
12.19, 12.21, & 12.33 copyright 1971 by United
States Steel Corporation. Figure 9.30 courtesy
of Republic Steel Corporation.)
ex: structure vs cooling rate of steel
• Processing can change structure
Structure, Processing, & Properties
Hardness
(BHN)
Cooling Rate (ºC/s)
100
200
300
400
500
600
0.01 0.1 1 10 100 1000
(d)
30 μm
(c)
4 μm
(b)
30 μm
(a)
30 μm