Introduction
EN113 Engineering Materials
& Properties
Dr. S. K. Ales, PhD
BE & MTech (PNGUT, PG), PNGUT; ME (SAU CN); PhD (AUT, NZ)
Department of Mechanical Engineering
PNG University of Technology
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Today’s Lecture
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Administrative issues (syllabus, etc.)
Introduction to materials engineering
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Important Information
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Meeting time and place
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Textbook (recommended)
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CT208 (tutorials/Assignments/Tests)
W.D. Callister, Materials Science and
Engineering: An Introduction, 9th ed.
Prerequisites
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Earlier versions of W.D. Callister, Materials
Science and Engineering: An Introduction
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1Attendance
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Course Requirements
1. You are expected and required to attend all classes of this course.
Since this course is too difficult to study by yourself , it is particularly
important for you to be in class to benefit from all that your fellow students
and instructor have to offer.
2. You can leave messages for me at steve.korokan@pnguot.ac.pg
3. Grading Guidelines:
(1) 2 x Assignments : weight 10% ;
(2) 2 x Tests : weight 20%;
(3) 3 x Laboratory: weight 20% ;
(4)Final examination : weight 50% .
EN113 Final Subject outline will be issued soon.
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Lectures
Time:
See your time table
Location: DH/RKLT
Activities:
• Present new
material
• Announce reading and homework
• Take quizzes and midterms*
*Make-ups given only for emergencies.
*Discuss potential conflicts beforehand.
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Recitations
Instructor: tba
Times and Places:
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X:XXa
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X:XXp
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X:XXp
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X:XXa
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Purpose: m
• Discuss homework, quizzes, exams
• Hand back graded quizzes, exams
• Discuss concepts from lecture
Recitations start next week.
Try to attend your registered recitation.
If*necessary, attend an alternate recitation.
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Laboratory
Instructor/Lab Assistant: tba
Location: M6 Materials Science & Engineering lab
Purpose: To learn more about materials by relating
lecture material with observations. Also to learn to properly
formulate and write engineering reports and proposals.
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Teaching Assistants Roles
Nam
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Office
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Tel.
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Teaching Assistants will
• participate in recitation sessions,
• have office hours to help you with course material
and problem sets.
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Office Hours
*Contact lab assistants for special arrangements
Activities:
• Discuss homework, quizzes, exams
• Discuss lectures, book
• Pick up missed handouts
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Course Materials
Required textbook:
• Materials Science and Engineering: An Introduction,
W.D. Callister, Jr. and D.G. Rethwisch, 9th edition,
John Wiley and Sons, Inc. (2010).
References:
All earlier versions by W.D. Callister and D.G. Rethwisch
Google class ID:
c27rywg
Link: https://classroom.google.com/c/NDY1OTgwNTMzNjIx?cjc=c27rywg
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Overall Aim
Course Objective...
Introduce fundamental concepts in Materials
Science & Engineering
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
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Chapter 1 - Introduction
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What is materials science?
Why should we know about it?
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Materials drive our society
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Stone Age
Bronze Age
Iron Age
Now?
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Silicon Age?
Polymer Age?
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Development of Materials in history
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Components of Materials Engineering
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Materials science is the study of the
relationships between the structures and
properties of materials
Materials engineering is the design or
engineering of a material to produce the
desired properties
Components of materials engineering:
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Metals, Ceramics & Polymers
Familiar objects
made of metals and
metal alloys (from
left to right):
silverware (fork and
knife), scissors,
coins, a gear, a
wedding ring, and a
nut and bolt.
Adapted from
Callister Fig. 1.9 9E
Common objects made of
ceramic materials:
scissors, a china teacup,
a building brick, a floor
tile, and a glass vase.
Adapted from Callister
Fig. 1.10 9E
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Several common objects made of
polymeric materials: plastic tableware
(spoon, fork, and knife), billiard balls, a
bicycle helmet, two dice, a lawn mower
wheel (plastic hub and rubber tire), and a
plastic milk carton.
Adapted from Callister Fig. 1.11 9E
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Application Example – Hip Implant
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With age or certain illnesses joints deteriorate.
Particularly those with large loads (such as hip).
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Adapted from Fig. 22.25, Callister 7e.
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Application Example – Hip Implant
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Requirements
mechanical
strength (many
cycles)
good lubricity
biocompatibility
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Adapted from Fig. 22.24, Callister 7e.
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Application Example – Hip Implant
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Adapted from Fig. 22.26, Callister 7e.
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Hip Implant
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Key problems to overcome
■ fixation agent to hold
acetabular cup
■ cup lubrication material
■ femoral stem – fixing agent
(“glue”)
■ must avoid any debris in cup
Ball
Acetabular
Cup and Liner
Femoral
Stem
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Adapted from chapter-opening photograph,
Chapter 22, Callister 7e.
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Structure, Processing, & Properties
• Properties depend on structure
ex: hardness vs structure of steel
(d)
Hardness (BHN)
600
500
400
30 μm
(c)
(b)
(a)
4 μm
300
200
100
0.0
1
30 μm
0.
1
30 μm
Data obtained from Figs. 10.30(a)
and 10.32 with 4 wt% C composition,
and from Fig. 11.14 and associated
discussion, Callister & Rethwisch 8e.
Micrographs adapted from (a) Fig.
10.19; (b) Fig. 9.30;(c) Fig. 10.33;
and (d) Fig. 10.21, Callister &
Rethwisch 8e.
1
10 100 1000
Cooling Rate (ºC/s)
• Processing can change structure
ex: structure vs cooling rate of steel
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Types of Materials
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Metals:
– Strong, ductile
– High thermal & electrical conductivity
– Opaque, reflective.
• Polymers/plastics: Covalent bonding 🡪 sharing of e’s
– Soft, ductile, low strength, low density
– Thermal & electrical insulators
– Optically translucent or transparent.
• Ceramics: ionic bonding (refractory) – compounds of metallic
& non-metallic elements (oxides, carbides, nitrides, sulfides)
– Brittle, glassy, elastic
– Non-conducting (insulators)
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The Materials Selection Process
1. Pick Application
Determine required Properties
Properties: mechanical, electrical, thermal,
magnetic, optical, deteriorative.
2. Propertie
Identify candidate Material(s)
s Material: structure, composition.
3. Material
Identify required
Processing
Processing: changes
structure and overall shape
ex: casting, sintering, vapor deposition, doping
forming, joining, annealing.
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Example:
Selection Criteria for Beverage Container
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provide a barrier to the passage of carbon dioxide,
which is under pressure in the container;
be nontoxic, unreactive with the beverage, and,
preferably be recyclable;
be relatively strong, and capable of surviving a drop
from a height of several feet when containing the
beverage;
be inexpensive and the cost to fabricate the final
shape should be relatively low;
if optically transparent, retain its optical clarity;
capable of being produced having different colors
and/or able to be adorned with decorative labels. 23
Example:
Aluminum alloy is relatively strong (but easily
dented), is a very good barrier to the diffusion
of carbon dioxide, is easily recycled,
beverages are cooled rapidly, and labels may
be painted onto its surface, however they are
opaque and expensive
to produce.
Glass is impervious to the passage of
carbon dioxide, is a relatively
inexpensive material, may be recycled,
but it cracks and fractures easily, and
glass bottles are relatively heavy
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Plastic is relatively strong, may be
made optically transparent ,is
inexpensive and lightweight, and is
recyclable, it is not as impervious to
the passage of carbon dioxide as
aluminum and glass
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Electrical
• Electrical Resistivity of
Copper: 6
4
3
(10-8
Ohm-m)
Resistivity, ρ
5
2
1
0
Cu
+
3.32
i
t%N
a
i
%N
t
a
Ni
16
.
%
t
2
+
12 a
.
Cu
1
u+
C
med
i
r
o
f
%N
t
de
a
1.12
+
Cu
Cu
”
e
r
“Pu
-20
0
-10
0
0
Adapted from Fig. 18.8, Callister &
Rethwisch 8e. (Fig. 18.8 adapted
from: J.O. Linde, Ann Physik 5, 219
(1932); and C.A. Wert and R.M.
Thomson, Physics of Solids, 2nd
edition, McGraw-Hill Company, New
York, 1970.)
T (ºC)
• Adding “impurity” atoms to Cu increases resistivity.
• Deforming Cu increases
resistivity.
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Thermal
-- Silica fiber insulation
offers low heat conduction.
Adapted from
chapter-opening
photograph, Chapter 17,
Callister & Rethwisch
3e. (Courtesy of
Lockheed
Missiles and Space
Company, Inc.)
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100
μm
• Thermal Conductivity
of Copper:
-- It decreases when
you add zinc!
Thermal Conductivity
(W/m-K)
• Space Shuttle Tiles:
Adapted from
Fig. 19.4W, Callister
6e. (Courtesy of
Lockheed Aerospace
Ceramics Systems,
Sunnyvale, CA)
(Note: "W" denotes fig.
is on CD-ROM.)
40
0
30
0
20
0
10
0
0
0
1
2
3
4
Composition
(wt%
0
0
0
0
Adapted
from Fig. 19.4, Callister & Rethwisch
Zinc)
8e. (Fig. 19.4 is adapted from Metals Handbook:
Properties and Selection: Nonferrous alloys and
Pure Metals, Vol. 2, 9th ed., H. Baker,
(Managing Editor), American Society for Metals,
1979, p. 315.)
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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
Adapted
from C.R. Barrett, W.D.
Field
Fig. 20.23, Callister & Rethwisch 8e.
Nix, and
A.S. Tetelman, The Principles of
Engineering Materials, Fig. 1-7(a), p. 9,
1973.
Electronically reproduced
by permission of Pearson Education, Inc.,
Upper Saddle River, New Jersey.
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Optical
• Transmittance:
-- Aluminum oxide may be transparent, translucent, or
opaque depending on the material structure.
single crystal
polycrystal:
low porosity
polycrystal:
high porosity
Adapted from Fig. 1.2,
Callister & Rethwisch 8e.
(Specimen preparation,
P.A. Lessing; photo by S.
Tanner.)
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Deteriorative
-- causes cracks!
• Heat treatment: slows
crack speed in salt water!
crack speed (m/s)
• Stress &
Saltwater...
1 8
0
1 -1
0
0
Adapted from chapter-opening photograph,
Chapter 16, Callister & Rethwisch 3e.
(from Marine Corrosion, Causes, and
Prevention, John Wiley and Sons, Inc., 1975.)
“as-is
”“held at
160ºC for 1 hr
before
Alloy 7178 tested in
testing”
saturated aqueous NaCl
solution at 23ºC
increasing load
Adapted from Fig. 11.20(b), R.W. Hertzberg, "Deformation and
Fracture Mechanics of Engineering Materials" (4th ed.), p. 505, John
Wiley and Sons, 1996. (Original source: Markus O. Speidel, Brown
Boveri Co.)
-- material:
4 μm
7150-T651 Al "alloy"
(Zn,Cu,Mg,Zr)
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Adapted from Fig. 11.26,
Callister & Rethwisch 8e. (Provided courtesy of G.H.
Narayanan and A.G. Miller, Boeing Commercial Airplane
Company.)
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Advanced Materials
▪ Semiconductors have intermediate properties between metals (conductors) and
ceramics/Polymers. For example,
integrated circuitry that have totally
revolutionised the electronics and computer industries
▪ Biomaterials are employed in components implanted into the human body to
replace diseased or damaged body parts. These materials must not produce toxic
substances and must be compatible with body tissues (i.e., must not cause
adverse biological reactions). All of the preceding materials—metals, ceramics,
polymers, composites, and semiconductors— may be used as biomaterials.
▪ Smart (or intelligent) materials are a group of new and state-of-the-art materials
now being developed that will have a significant influence on many of our
technologies
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Advanced Materials
▪ Nanomaterials are those that have structural features on the order
of a nanometer, some of which may be designed on the
atomic/molecular level). They can be metal, ceramic, polymer or
composites.
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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.
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Homework
Problem 1.1: Select one or more of the following modern items or devices and
conduct an Internet search in order to determine what specific material(s) is (are)
used and what specific properties this (these) material(s) possess(es) in order for
the device/item to function properly. Finally, write a short essay in which you
report your findings:
a)Cell phone
b)PCB (Printed Circuit Boad)
(c)digital camera batteries
d)Cell phone displays
e)Solar cells
(f)Wind turbine blades
g)Automobile engine blocks (other than cast iron)
h)Automobile bodies (other than steel alloys)
•Space telescope mirrors
•Military body armor
a)Sports equipment
b)Soccer balls/Basketballs
(c)Ski poles
d)Ski boots
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