1. Material Science
Introduction

2. What are Materials? That’s easy! Look around.
Our clothes are made of materials, our homes are made of materials - mostly manufactured. Glass windows, vinyl siding, metal silverware, ceramic dishes…
Most things are made from many different kinds of materials.

3. Materials Science and Engineering
It all about the raw materials and how they are processed
That is why we call it materials ENGINEERING
Minor differences in Raw materials or processing parameters can mean major changes in the performance of the final material or product

4. Materials Science and Engineering
An interdisciplinary study that combines metallurgy, physics, chemistry, and engineering to solve real-world problems with real-world materials in an acceptable societal and economical manner. (VCSU, 2006)

5. 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

6. Materials Science - Example
The dramatic role of iron throughout the ages is not really the result of it being "strong". In reality, iron has been important because we can change its properties by heating and cooling it.
The ability to change the properties and/or behavior of a material is what makes most materials useful and this is at the heart of materials science! (MSECRC, 2006)

7. History of Materials
Man has been studying materials since before leaving the cave.
Due to lack of communication, early man spent hundreds of millennia experimenting with stone tools.
The first metal tools appeared perhaps only six thousand years ago.

8. History of Materials
The discovery of “Iceman” in the Alps in 1991 gave significant information on early Copper age. He was carrying a copper axe.
It is dated at about 5300 years, when the first pyramids were built.

9. History of Materials
As our knowledge of materials grows, so does the sophistication of our tools.
The more sophisticated our tools, the more sophisticated our accomplishments.

10. 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 …

11. 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!

12. 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.

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

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

15. 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

16. Introduction List the Major Types of MATERIALS That You Know: METALS
CERAMICS
POLYMERS
SEMICONDUCTORS
COMPOSITES
ADVANCED MATERIALS

17. Kinds of Materials
Metals: are materials that are normally combinations of "metallic elements". Metals usually are good conductors of heat and electricity. Also, they are quite strong but malleable and tend to have a lustrous look when polished.
Ceramics: are generally compounds between metallic and nonmetallic elements. Typically they are insulating and resistant to high temperatures and harsh environments. (MSECRC, 2006)

18. Several uses of steel and pressed aluminum.
Metals
Several uses of steel and pressed aluminum.

19. Ceramics
Examples of ceramic materials ranging from household to high performance combustion engines which utilize both metals and ceramics.

20. Kinds of Materials
Polymers: (or plastics) are generally organic compounds based upon carbon and hydrogen. They are very large molecular structures. Usually they are low density and are not stable at high temperatures.
Semiconductors: have electrical properties intermediate between metallic conductors and ceramic insulators. Also, the electrical properties are strongly dependent upon small amounts of impurities. (MSECRC, 2006)

21. Polymers include “Plastics” and rubber materials

22. Semiconductors
Micro-Electrical-Mechanical Systems (MEMS)
Si wafer for computer chip devices.

23. Kinds of Materials
Composites: consist of more than one material type. Fiberglass, a combination of glass and a polymer, is an example. Concrete and plywood are other familiar composites. Many new combinations include ceramic fibers in metal or polymer matrix. (MSECRC, 2006)

24. Composites
Polymer composite materials: reinforcing glass fibers in a polymer matrix.

25. Newer Branches of Materials Science
Nanotechnology: a relatively new area grown out of techniques used to manufacture semiconductor circuits. Machines can be produced on a microscopic level. Example - miniature robots to do surgery inside the body or miniature chemical laboratories and instruments that will continuously analyze blood and dispense medications inside the body. (VCSU, 2006)

26. NanoTech
As Hygienic as a Shark? Yes, they avoid pesky algae and bacteria by way of an ingenious skin design. Microorganisms prefer flat surfaces, which allow them to form large colonies or biofilms. But unlike most other fish, sharks don't have flat scales. Instead, they have dermal denticles—ridged, tooth-like scales covering their body (pictured here). These bumpy "teeth" create a rough surface that biofilms can't colonize or thrive on, which contributes to the shark's naturally bacteria-free status.
In the not too distant future, dozens of intriguing nanodevices such as the nanotubes above may transform cancer diagnosis, treatment, and prevention.

27. Introduction, cont. 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.

28. 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

29. 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, doping, annealing.

30. Processing can change structure! (see above structure vs Cooling Rate)
But:
Properties depend on Structure (strength or hardness)
(d)
30 mm 6 00 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)

31. Another Example: Rolling of Steel
At h1, L1
low tensile strength
low yield strength
high ductility
round grains
At h2, L2
high tensile strength
high yield strength
low ductility
elongated grains
Structure determines Properties but Processing determines Structure!

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

33. 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.)

34. 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.)

35. 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.)

36. 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.)

37. Goal is to 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.

38. Future of Material Science
Design of materials having specific desired characteristics directly from our knowledge of atomic structure.
Miniaturization: “Nanostructured" materials, with microstructure that has length scales between 1 and 100 nanometers with unusual properties. Electronic components, materials for quantum computing.
Smart materials: airplane wings that deice or move themselves, buildings that stabilize themselves in earthquakes…

39. Future of Material Science
Environment-friendly materials: biodegradable or photodegradable plastics, advances in nuclear waste processing, etc.
Learning from Nature: shells and biological hard tissue can be as strong as the most advanced laboratory-produced ceramics, mollusks produce biocompatible adhesives that we do not know how to reproduce…
Materials for lightweight batteries with high storage densities, for turbine blades that can operate at 2500°C, room-temperature superconductors? chemical sensors (artificial nose) of extremely high sensitivity, cotton shirts that never require ironing…