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Chapter 1 - 1
Materials Science, ENGR45
Materials science is a multidisciplinary field focusing
on functional solids, whether the function served is
structural, electronic, thermal, chemical, magnetic,
optical, or some combination of these. It uses those
parts of chemistry and physics that deal with the
properties of materials, but also includes a distinctive
set of scientific techniques that probe materials
structure. ...
en.wikipedia.org/wiki/Materials_science
My definition: Materials Science is a field of
Engineering/Science for those who can’t make up
their mind which field of Science and Engineering
they like the best!
Chapter 1 - 2
Chapter 1 - Introduction
• Why should we know learn what materials are?
Materials drive our society
– Stone Age
– Bronze Age
– Iron Age
– Now?
• Silicon Age?
• Polymer Age?
Chapter 1 - 3
Types of Materials
• 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)
Chapter 1 - 4
Also..
Composites
Semiconductors
Biomaterials
Smart materials
…….
.And NANO-MATERALS
Chapter 1 - 5
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.
Chapter 1 - 6
ELECTRICAL
• Electrical Resistivity of Copper:
6
Adapted from Fig. 18.8, Callister 7e.
(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.)
(10-8 Ohm-m)
Resistivity, r
5
4
3
2
1
0
-200
-100
0
T (°C)
• Adding “impurity” atoms to Cu increases resistivity.
• Deforming Cu increases resistivity.
Chapter 1 - 7
THERMAL
• Space Shuttle Tiles:
• Thermal Conductivity
of Copper:
--Silica fiber insulation
offers low heat conduction.
Thermal Conductivity
(W/m-K)
Adapted from chapteropening photograph,
Chapter 19, Callister 7e.
(Courtesy of Lockheed
Missiles and Space
Company, Inc.)
--It decreases when
you add zinc!
100 mm
Adapted from
Fig. 19.4W, Callister
6e. (Courtesy of
Lockheed Aerospace
Ceramics Systems,
Sunnyvale, CA)
(Note: "W" denotes fig.
is on CD-ROM.)
400
300
200
100
0
0
10
20 30 40
Composition (wt% Zinc)
Adapted from Fig. 19.4, Callister 7e.
(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.)
Chapter 1 - 8
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 7e.
(Fig. 20.23 is from J.U. Lemke, MRS Bulletin,
Vol. XV, No. 3, p. 31, 1990.)
Adapted from C.R. Barrett, W.D. 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.
Chapter 1 - 9
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 7e.
(Specimen preparation,
P.A. Lessing; photo by S.
Tanner.)
Chapter 1 - 10
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.
Chapter 1 - 11
Greatest Materials Moments
Voted by more than 4,200
materials science and
engineering professionals from
68 countries attended the TMS
(The Minerals, Metals & Materials Society)
2007 Meeting in Florida.
Chapter 1 -
#10:
• Bessemer Process In 1856, Henry Bessemer.
This leads to the era of cheap, large tonnage
steel, enabling massive progress in
transportation, building construction and
general industrialization.
Chapter 1 -
#9:
• X-ray Diffraction In 1912 by Max
von Laue. This creates the means
to characterize crystal structures
and inspires the development of
the theory of diffraction by
crystals.
Chapter 1 -
#8:
• Cu Extraction and Casting Approximately
5000 B.C. by people in the region of modern
Turkey discover that liquid copper can be
extracted from malachite and azurite, and
that the molten metal can be cast into
different shapes. Extractive metallurgy is
introduced.
Chapter 1 -
#7:
• Crucible Steel Making Around 300 B.C., metal
workers in south India develop crucible steel
making, which produces "wootz" steel. This
becomes famous as Damascus sword steel
hundreds of years later, inspiring artisans,
blacksmiths and metallurgists for many
generations.
Chapter 1 -
#6:
Modern Concrete In 1755. John Smeaton
invents modern concrete (hydraulic cement),
which introduces the dominant construction
material of the modern age.
Chapter 1 -
#5:
Optical Microscopy In 1668. Anton van
Leeuwenhoek develops optical microscopy,
capable of magnifications of 200 times and
greater. This enables study of the natural
world invisible to the human eye.
Chapter 1 -
#4:
Invention of Glass Approximately 2200 B.C.,
northwestern Iranians invent glass. This
becomes the second greatest nonmetallic
engineering material (following ceramics).
Chapter 1 -
#3:
Transistor In 1948, John Bardeen, Walter H.
Brattain and William Shockley invent the
transistor. This becomes the building block
for all modern electronics and the foundation
for microchip and computer technology.
Chapter 1 -
#2:
Iron Smelting Around 3500 B.C. Egyptians
smelt iron for the first time, using tiny
amounts, mostly for ornamental or
ceremonial purposes. This is the first
processing secret of what will become the
world's dominant metallurgical material.
Chapter 1 -
#1:
The Periodic Table of Elements
devised by Dmitri Mendeleev in
1864 was voted the number one
materials moment, the
indispensable reference tool for
those in the field.
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