1. Introduction to Material Science

2. Materials Science and Engineering
The discipline of investigating the relationships that exist between the structures and properties of materials.
Materials Engineering
The discipline of designing or engineering the structure of a material to produce a predetermined set of properties based on established structure-property correlation.
Four Major Components of Material Science and Engineering:
Structure of Materials
Properties of Materials
Processing of Materials
Performance of Materials

3. And Remember: Materials “Drive” our Society!
Ages of “Man” we survive based on the materials we control
Stone Age – naturally occurring materials
Special rocks, skins, wood
Bronze Age
Casting and forging
Iron Age
High Temperature furnaces
Steel Age
High Strength Alloys
Non-Ferrous and Polymer Age
Aluminum, Titanium and Nickel (superalloys) – aerospace
Silicon – Information
Plastics and Composites – food preservation, housing, aerospace and higher speeds
Exotic Materials Age?
Nano-Material and bio-Materials – they are coming and then …

4. Doing Materials! Engineered Materials are a function of:
Raw Materials Elemental Control
Processing History
Our Role in Engineering Materials then is to understand the application and specify the appropriate material to do the job as a function of:
Strength: yield and ultimate
Ductility, flexibility
Weight/density
Working Environment
Cost: Lifecycle expenses, Environmental impact*
* Economic and Environmental Factors often are the most important when making the final decision!

5. Example of Materials Engineering Work – Hip Implant
With age or certain illnesses joints deteriorate. Particularly those with large loads (such as hip).
Adapted from Fig , Callister 7e.

6. Example – Hip Implant Requirements mechanical strength (many cycles)
good lubricity
biocompatibility
Adapted from Fig , Callister 7e.

7. Example – Hip Implant
Adapted from Fig , Callister 7e.

8. Solution – Hip Implant Key Problems to overcome: Acetabular
Cup and Liner
Key Problems to overcome:
fixation agent to hold acetabular cup
cup lubrication material
femoral stem – fixing agent (“glue”)
must avoid any debris in cup
Must hold up in body chemistry
Must be strong yet flexible
Ball
Femoral
Stem

9. Types of Materials Major Types of Materials Other Materials METALS
CERAMICS
POLYMERS
Other Materials
COMPOSITES
ELECTRONIC MATERIALS
ADVANCED MATERIALS

10. Materials Metals Ceramics Polymers Composites
Steel, Cast Iron, Aluminum, Copper, Titanium, many others
Ceramics
Glass, Concrete, Brick, Alumina, Zirconia, SiN, SiC
Polymers
Plastics, Wood, Cotton (rayon, nylon), “glue”
Composites
Glass Fiber-reinforced polymers, Carbon Fiber-reinforced polymers, Metal Matrix Composites, etc.

11. Metals Ceramics Some of these have descriptive subclasses.
Classes have overlap, so some materials fit into more than one class.
Metals
Iron and Steel
Alloys and Superalloys (e.g. aerospace applications)
 Intermetallic Compounds (high-T structural materials)
Ceramics
Structural Ceramics (high-temperature load bearing)
Refractories (corrosion-resistant, insulating)
Whitewares (e.g. porcelains)
Glass
Electrical Ceramics (capacitors, insulators, transducers, etc.)
 Chemically Bonded Ceramics (e.g. cement and concrete)

12. Biomaterials (really using previous 5, but bio-mimetic)
Polymers
 Plastics
Liquid crystals
Adhesives
Composites
Particulate composites (small particles embedded in a different material)
Laminate composites (golf club shafts, tennis rackets, Damaskus swords)
Fiber reinforced composites (e.g. fiberglass)
Electronic Materials
Silicon and Germanium
III-V Compounds (e.g. GaAs)
Photonic materials (solid-state lasers, LEDs)
Biomaterials (really using previous 5, but bio-mimetic)
Man-made proteins (cytoskeletal protein rods or “artificial bacterium”)
Biosensors (Au-nanoparticles stabilized by encoded DNA for anthrax detection)
Drug-delivery colloids (polymer based)

13. Thoughts about these “fundamental” 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)
Metals have high thermal & electrical conductivity because valence electrons are free to roam

14. The Materials Selection Process1.
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.

15. ASHBY “Strength-Density” Material Selection Diagram

16. Detailed diagram for Metals Detailed diagram for ceramics

17. ASHBY “Strength-Ductility” Material Selection Diagram

18. ASHBY “Strength-Cost” Material Selection Diagram

19. Processing can change structure! (see above structure vs Cooling Rate)
Properties of Materials (ex: Strength or Hardness, etc.) Depend on Structure
(d)
30 mm 6 00
Example: 1080 Steel 5 00
(c)
4 mm 4 00
(b)
30 mm
(a)
30 mm
Hardness (BHN) 3 00 2 00
100
0.01
0.1 1 10
100
1000
Cooling Rate (ºC/s)
And:
Processing can change structure! (see above structure vs Cooling Rate)

20. Another Example: Rolling of Steel
At h1, L1
low UTS
low YS
high ductility
round grains
At h2, L2
high UTS
high YS
low ductility
elongated grains
Structure determines Properties but Processing determines Structure!

21. Optical Properties of Ceramic are controlled by “Grain Structure”
Grain Structure is a function of “Solidification” processing!

22. Electrical Properties (of Copper):
T (°C)
-200
-100
Cu at%Ni
Cu at%Ni
deformed Cu at%Ni 1 2 3 4 5 6
Resistivity, r
(10-8 Ohm-m)
Cu at%Ni
“Pure” Cu
Electrical Resistivity of Copper is affected by:
Contaminate level
Degree of deformation
Operating temperature
Adapted from Fig. 18.8, Callister 7e.
(Fig 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.)

23. THERMAL Properties • Space Shuttle Tiles: • Thermal Conductivity
--Silica fiber insulation
offers low heat conduction.
• Thermal Conductivity
of Copper: --It decreases when
you add zinc!
Composition (wt% Zinc)
Thermal Conductivity
(W/m-K)
400
300
200
100 10 20 30 40
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.)
Adapted from Fig. 19.4, Callister 7e.
(Fig 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.)

24. MAGNETIC Properties • Magnetic Permeability vs. Composition:
--Adding 3 atomic % Si makes Fe a better recording medium!
• Magnetic Storage:
--Recording medium
is magnetized by
recording head.
Magnetic Field
Magnetization
Fe+3%Si Fe
Adapted from C.R. Barrett, W.D. Nix, and
A.S. Tetelman, The Principles of
Engineering Materials, Fig. 1-7(a), p. 9,
Electronically reproduced
by permission of Pearson Education, Inc.,
Upper Saddle River, New Jersey.
Fig , Callister 7e.
(Fig is from J.U. Lemke, MRS Bulletin,
Vol. XV, No. 3, p. 31, 1990.)

25. DETERIORATIVE Properties
• Heat treatment: slows
crack speed in salt water!
• Stress & Saltwater...
--causes cracks!
“held at
160ºC for 1 hr
before testing”
increasing load
crack speed (m/s)
“as-is” 10
-10 -8
Alloy 7178 tested in
saturated aqueous NaCl
solution at 23ºC
Adapted from Fig (b), R.W. Hertzberg, "Deformation and Fracture Mechanics of Engineering Materials" (4th ed.), p. 505, John Wiley and Sons, (Original source: Markus O. Speidel, Brown Boveri Co.)
4 mm
--material:
7150-T651 Al "alloy"
(Zn,Cu,Mg,Zr)
Adapted from Fig ,
Callister 7e. (Fig provided courtesy of G.H.
Narayanan and A.G. Miller, Boeing Commercial
Airplane Company.)
Adapted from chapter-opening photograph, Chapter 17, Callister 7e.
(from Marine Corrosion, Causes, and Prevention, John Wiley and Sons, Inc., 1975.)

26. Courses on Materials Science will make you aware of the importance of Material Selection by:
• Using the right material for the job.
one that is most economical and “Greenest” when life usage is considered
• Understanding the relation between properties, structure, and processing.
• Recognizing new design opportunities offered
by materials selection.