Post on 20-Jan-2018
description
Chapter 1-
Reading: Chapter 1 & 2. Class notes are in:WEB SITE
HW # 1: due Thursday, September 4, 2008: Problems 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7
0
ANNOUNCEMENTS
Chapter 1-
CHEN 313: Materials Science and Engineering
Course Objective...Introduce fundamental concepts in Materials S&T
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
a
Chapter 1-
Lecturer: Dr Jorge Seminario
Time: Tu&Th 2:20-3:35 pm
Make up or additional classes: Tu or Th 7 PM (TBA)
Location: CHEN 106
b
LECTURES
Chapter 1-
Teaching Assistants will grade your homework and exams
Notice: goals of exams and HW are different
One teaching assistant!Three graders!!!
d
TEACHING ASSISTANTSwe have one now!!
Chapter 1-
In my office: Wednesdays: 4:30-5:20 PMThursdays: 3-4 PM
In cyber-space: 24-7
Due to the large number of students virtual office hours will be preferred
Responses to all studentse
OFFICE HOURS
Chapter 1-• other books
Required text:Fundamentals of Materials Science and Engineering: An Integrated Approach3rd Edition
W.D. Callister, Jr. and D. G. RethwischJohn Wiley and Sons, Inc. (2007).
Both book and accompanying CD-ROM are useful.
Other Materials:• papers
COURSE MATERIAL
Chapter 1-
exam # 1 15%
exam #2 15%
exam #3 15%
final 40%
g
GRADING
Homework, class participation: 15%projects, group work, quizes, etc.
Chapter 1-
Materials are... engineered structures...not blackboxes!
Structure...has many dimensions...
Structural feature Dimension (m)atomic bondingmissing/extra atomscrystals (ordered atoms)second phase particlescrystal texturing
< 10-10 10-10
10-8-10-110-8-10-4> 10-6
1
CHAPTER 1: MATERIALS SCIENCE & ENGINEERING
Chapter 1-
Introduction• Materials Science. Investigation of the relationships
between the structures and properties of materials– How do the arrangement of a materials components (e.g.
atoms, etc.) influence its properties (e.g. does it conduct electrons or not)?
• Materials Engineering. Designing the structure of a material so that it has desired properties.
UNCLASSIFIED
Future Force Warrior: Technical Challenges for Dismounted Soldier
Substantial Weight Savings/Low Bulk
Ballistic, Chem/Bio, EM Protection
Integrated Combat Suit
Electro-Textile Power/Data Body LAN, Embedded Sensors & Antenna Array
NanoElectronics and NanoPhotonicsEnabling Technology for the Future Force Warriors
Enabled by Nanomaterials Electro-TextilesElectro-TextilesCompact PowerCompact Power
Micro-Cooling & HeatingMicro-Cooling & HeatingEmbedded Nano-Micro SensorsEmbedded Nano-Micro SensorsChem-Bio Detection/ProtectionChem-Bio Detection/Protection
Communications/Data Body LANCommunications/Data Body LANSignature ManagementSignature Management
Durable Layer Durable Layer with Advanced with Advanced Camouflage Camouflage
Selectively Permeable Selectively Permeable Chemical Biological Chemical Biological BarrierBarrier
Spacer Fabric for Spacer Fabric for Conditioned Air FlowConditioned Air Flow
Soft Body Armor Soft Body Armor
Embedded Embedded Sensors & Sensors & Data/Power Data/Power BusBus
Ambient Air Ambient Air FlowFlow
Enhance warrior’s ability to fight and survive in any mission/environment.
Integrate functions and enable “plug-and-play” capabilities tailored to mission.
Physical/electrical interfaces for Future Force Warrior equipment.
UNCLASSIFIED
Chapter 1-
Chapter 1-
Chapter 1-
Introduction
• Another view of this course:– Macroscopic versus microscopic
• Engineers typically are interested in macroscopic properties (e.g. heat capacities, viscosity, fracture strength, etc.)
• Scientists often describe things in microscopic terms (e.g. bond strength, orbital theory, etc.)
• However, recent trends tend to mix both approaches: Engineers and Scientists both look at micro and macroscopic properties and try to understand the connection between them
– In this class I am going to, whenever possible, show the interrelationship between microscopic and macroscopic properties
Chapter 1-
Introduction
• Processing/Structure/Properties/Performance– They are interrelated!
Processing Structure Properties Performance
• As engineers you are probably more tuned into processing and performance• However, how processing influences the structure is critical• Why? This will influence the material properties, which of
course affect its performance!
Chapter 1-
Introduction
• What do I mean by structure?– Structure is related to the arrangement of a material’s
components• This could be on any length scale• Atomic, nano-, micro-, macro-
– All of these length scales matter!
Types of Carbon (just plain old carbon!)
Diamond Graphite C60 - Fullerene Carbon nanotubes
Chapter 1-
Introduction
• Properties
– How the material behaves in terms of the kind and magnitude of response to an imposed stimulus
– What are the stimuli?• Temperature• Magnetic field• Electric field
– material properties are typically defined independent of material shape and size!
– However… what about nanosize objects?
Chapter 1-
Introduction
• Properties– For the purposes of this course we will group properties into six
categories• Mechanical• Electrical• Thermal• Magnetic• Optical• Deteriorative
Chapter 1-
Introduction
Property Example (Physics) Example Properties
Mechanical Rate of material deformation to an applied load
Elastic modulus
Electrical Response of material to an applied electrical field
Electrical conductivity
Thermal Material expansion/contraction with change in temperature
Heat capacity, thermal
conductivity
Magnetic Response of a material to an applied magnetic field
Magnetic susceptibility
Optical Response of material to electromagnetic radiation
Refractive index
Deteriorative Rate of decomposition of material (often in presence of acid, etc.)
Corrosion rate
Chapter 1-
Introduction
• Processing Structure Properties
Same material – aluminum oxide. Depending on structure (which is influenced by processing) materials are transparent, translucent, opaque
Chapter 1-
Introduction
• Classification of Materials– In materials science there have typically been three
categories of materials• Metals• Ceramics• Polymers
– I will also use this convention; in addition there are several others that are variants (or combinations) of the three
• Composites• Semiconductors• Biomaterials
Material Categories
• Materials can be divided into five broad categories:– Ceramics– Polymers (plastics)– Composite materials– Metals and alloys– Liquids and gases
Material Categories• Materials can be divided into five broad categories:
– Ceramics– Polymers– Composite materials– Metals and alloys
• Provide high strength, stiffness, relatively easy to process– Liquids and gases Metal and alloys used for the construction
of bridges and ships
Chapter 1-
Introduction
• Metals– Defining characteristic of a metal
• High number of delocalized electrons– What does this mean? -- The electrons (outer valence e-’s of
the various atoms) are not bound to particular atoms– Impact delocalization has on properties? Metals are:
» Good conductors of heat and electricity» Not transparent to visible light» Mechanically they are strong, yet deformable
• Examples – silver, gold, platinum, copper
Chapter 1-
Introduction
• Ceramics– “Between” metallic and nonmetallic compounds
• Oxides, nitrides, and carbides• These materials are typically insulators of heat and electricity• More resistant to high temperature (e.g. high melting points)
and harsh environments (e.g. pH) than metals• Mechanically – ceramics are hard but brittle
• Examples: silica (glass), alumina, silicon nitride
Material Categories
• Materials can be divided into five broad categories:– Ceramics
• Fusion of powders (e.g, aluminum oxide) under high pressure and temperature. Properties: High temperature resistance, relatively high strength, brittle, hard, corrosion resistant
– Polymers (plastics)– Composite materials– Metals and alloys– Liquids and gases
Chapter 1-
Introduction
• Polymers– Plastics and rubber materials
• Macromolecules – generally formed from carbon, nitrogen, oxygen and hydrogen (chon systems or molecules)
• there are polymers that contain metals• Usually have low densities• Can be extremely flexible• Not stable at high temperatures typically
• Examples: polyethylene, polystyrene, polyamide (Nylon®)
*CH2
H2C
*n
*CH
H2C
*n
*
HN
R
HN R'
O
*
O
n
Material Categories
• Materials can be divided into five broad categories:– Ceramics– Polymers
• Include plastics and rubbers. Properties: Easy to fabricate, low weight, low cost, good insulators, low temperature resistance, weak, compliant and durable
– Composite materials– Metals and alloys– Liquids and gases
Chapter 1-
Introduction
• Composites– Exactly what it sounds like: a new material that
consists of more than one component• Fiberglass – glass fibers embedded in a polymeric matrix• Idea – get desirable features of each material component• Complicated though – does not always work out as well as
you’d like
Material Categories• Materials can be divided into five broad categories:
– Ceramics– Polymers– Composite materials
• Combination of different materials (reinforcing component and binder). Properties: High strength to weight ratios, low weight, high stiffness, brittle
– Metals and alloys– Liquids and gases
Experimental aircraft: Entire body composed of composites
Chapter 1-
Introduction
• Semiconductors– Materials with electrical properties intermediate of a
metal (good conductor) and a ceramic (good insulator)– Silicon is the essential example – computer chips
• Key to use of semiconductors is the extremely precise control of dopant atoms that are used to manipulate the conducting properties
Chapter 1-
Introduction
• Biomaterials– Use of the above materials in life science applications– Key point: the material must not lead to an adverse
physiological reaction– Hip implants are the big success story here
Material Categories
• Materials can be divided into five broad categories:– Ceramics– Polymers– Composite materials– Metals and alloys– Liquids and gases
• Play a major role in heat transfer (e.g, radiator), hydraulic and pneumatic systems, lubrication
ex: hardness vs structure of steel • Properties depend on structure
Data obtained from Figs. 10.21(a)and 10.23 with 4wt%C composition,and from Fig. 11.13 and associateddiscussion, Callister 6e.Micrographs adapted from (a) Fig.10.10; (b) Fig. 9.27;(c) Fig. 10.24;and (d) Fig. 10.12, Callister 6e.
ex: structure vs cooling rate of steel • Processing can change structure
Structure, Processing, & Properties
Cooling Rate (C/s)100200300400500600
0.01 0.1 1 10 100 1000
(a)
30m
(b)
30m
(d)
30m(c)
4m
Brin
ell Hardness N
umbe
r (BH
N)
Brinell hardness test
(BHN)
Chapter 1-
1. Pick Application Determine required Properties
2. Properties Identify candidate Material(s)
3. Material Identify required ProcessingProcessing: changes structure and overall shapeex: casting, sintering, vapor deposition, doping forming, joining, annealing.
Properties: mechanical, electrical, thermal,magnetic, optical, deteriorative.
Material: structure, composition.
3
The Materials Selection Process
Material Selection Considerations
• Properties, Processing, Cost, Availability• Importance of each one depends on application:
– Military and Space applications pushing material properties and processing to their limits more important than cost
Chapter 1-
Advances in materials(see pdf in website)
Materials Process Design and Control LaboratoryMaterials Process Design and Control Laboratory
CCOORRNNEELLLL U N I V E R S I T Y
MATERIALS DESIGN FRAMEWORK
Machine learning schemes
Microstructure Information library
Accelerated Insertion of new
materials
Optimization of existing
materials
Tailored application specific material
properties
Virtual process simulations to
evaluate alternate designs
Computational process design
simulator
Virtual materials design
framework
Materials Process Design and Control LaboratoryMaterials Process Design and Control Laboratory
CCOORRNNEELLLL U N I V E R S I T Y
DESIGNING MATERIALS WITH TAILORED PROPERTIES
Micro problem driven by the velocity gradient L
Macro problem driven by the macro-design
variable βBn+1
Ω = Ω (r, t; L)~Polycrystal
plasticityx = x(X, t; β)
L = L (X, t; β)ODF: 1234567
L = velocity gradient
Fn+1
B0
Reduced Order Modes
Data mining techniques
Multi-scale Computation
Design variables (β) are macrodesign variables Processing sequence/parameters
Design objectives are micro-scale
averaged material/processproperties
Database
Chapter 1-
T (°C)-200 -100 0
Cu + 3.32 at%Ni
Cu + 2.16 at%Ni
deformed Cu + 1.12 at%Ni
123456
Resis
tivity
,
(10-
8 Oh
m-m
)
0
Cu + 1.12 at%Ni
“Pure” Cu
• Electrical Resistivity of Copper:
• Adding “impurity” atoms to Cu increases resistivity.• Deforming Cu increases resistivity.
4
Adapted from Fig. 18.8, Callister 6e.(Fig. 18.8 adapted from: J.O. Linde,Ann Physik 5, 219 (1932); andC.A. Wert and R.M. Thomson,Physics of Solids, 2nd edition,McGraw-Hill Company, New York,1970.)
ELECTRICAL
Chapter 1-
• Space Shuttle Tiles: --Silica fiber insulation offers low heat conduction.
• Thermal Conductivity of Copper: --It decreases when you add zinc!
Composition (wt%Zinc)Ther
mal
Con
duct
ivity
(W
/m-K
)
400
300200
10000 10 20 30 40
5
Fig. 19.0, Callister 6e.(Courtesy of LockheedMissiles and SpaceCompany, Inc.)
100m
Adapted fromFig. 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 6e.(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.)
THERMAL
Chapter 1-
• Magnetic Permeability vs. Composition: --Adding 3 atomic % Si makes Fe a better recording medium!
Magnetic FieldMag
netiz
atio
n
Fe+3%SiFe
Adapted from C.R. Barrett, W.D. Nix, andA.S. Tetelman, The Principles ofEngineering Materials, Fig. 1-7(a), p. 9,1973.Electronically reproducedby permission of Pearson Education, Inc.,Upper Saddle River, New Jersey.
Fig. 20.18, Callister 6e., (Fig. 20.18 is from J.U. Lemke, MRS Bulletin, Vol. XV, No. 3, p. 31, 1990.)
• Magnetic Storage: --Recording medium is magnetized by recording head.
MAGNETIC
Chapter 1-
• Transmittance: --Aluminum oxide may be transparent, translucent, or opaque depending on the material structure.
7
Adapted from Fig. 1.2,Callister 6e.(Specimen preparation,P.A. Lessing; photo by J. Telford.)
single crystalpolycrystal:low porosity
polycrystal:high porosity
OPTICAL
Chapter 1-
• Stress & Saltwater... --causes cracks!
• Heat treatment: slows crack speed in salt water!
4m
--material: 7150-T651 Al "alloy" (Zn,Cu,Mg,Zr)
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.)
8
Adapted from Fig. 17.0, Callister 6e.(Fig. 17.0 is from Marine Corrosion, Causes, and Prevention, John Wiley and Sons, Inc., 1975.)
Adapted from Fig. 11.24,Callister 6e. (Fig. 11.24 provided courtesy of G.H.Narayanan and A.G. Miller, Boeing CommercialAirplane Company.)
“held at 160C for 1hr before testing”
increasing loadcrac
k sp
eed
(m/s
)
“as-is”
10-10
10-8
Alloy 7178 tested in saturated aqueous NaCl solution at 23C
DETERIORATIVE
Chapter 1-
• Use the right material for the job.
• Understand the relation between properties, structure, and processing.
• Recognize new design opportunities offered by materials selection.
Course Goals:
9
SUMMARY