ME 2105 Introduction to Material Science (for Engineers) Dr. Richard R. Lindeke, Ph.D. B Met. Eng....
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Transcript of ME 2105 Introduction to Material Science (for Engineers) Dr. Richard R. Lindeke, Ph.D. B Met. Eng....
ME 2105 Introduction to Material Science (for Engineers)
Dr. Richard R. Lindeke, Ph.D. B Met. Eng. University of Minnesota, 1970 Master’s Studies, Met Eng. Colorado School of Mines, 1978-79 (Electro-Slag Welding of Heavy Section 2¼ Cr 1 Mo Steels) Ph.D., Ind. Eng. Penn State University, 1987 (Foundry Engineering – CG Alloy Development)
Syllabus and Website:
Review the Syllabus Attendance is your job – come to class! Final is Common Time at the Beginning of the Finals
Period Semi-Pop Quizzes and homework/Chapter Reviews (Ch
17 & 18) – (20% of your grade!) – note, additional homework (not to be collected) is suggested to prepare for quizzes and exams!
Don’t copy from others; don’t plagiarize – its just the right thing to do!!
Course Website: http://www.d.umn.edu/~rlindek1/ME2105/Cover_Page.htm
Our Text:
Materials Science for Engineering: an Introduction
By Callister & Rethwisch
8th Edition, Wiley, 2010.
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
Why the class?
As ME/IE we are involved in design of products or processes
When making up a design, what materials we use are critical (and driven by the function of the design)
When investigating processes, minor changes can have a major impact on the results
Materials Science and Engineering
Materials Science The discipline of investigating the relationships that
exist between the structures and properties (or performance) 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
Properties are a link between the fundamental issues of materials science and the practical
challenges of materials engineering. (FromG. E. Dieter, in ASM Handbook,Vol. 20: Materials
Selection and Design, ASM International, Materials Park, OH, 1997, p. 245.)
Material Selection in Design
And Remember: Materials “Drive” our Society!
Ages of “Man” and note, 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 and strong materials
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 …
A Timeline of Human Materials “Control”
And Formula One – the future of automotive is …http://www.autofieldguide.com/articles/050701.html
Looking At CG Iron Alloy Development (Processing):
Looking At CG Iron Alloy Development (Processing):
CG Structure – but with great care!
Good Structure 45KSI YS; 55KSI UTS
Poor “Too Little”
Poor “Too Much”
Looking At CG Iron Alloy Development (Structures)
Looking At CG Iron Alloy Development (Results)
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!
Introduction
List the Major Types of MATERIALS That You Know: METALS CERAMICS/Glasses POLYMERS COMPOSITES ADVANCED MATERIALS( Nano-
materials, electronic materials)
Introduction, cont. Metals
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.
Thoughts about these “fundamental” Materials
Metals: Strong, ductile high thermal & electrical conductivity opaque, reflective.
Ceramics: ionic bonding (refractory) – compounds of metallic & non-metallic elements (oxides, carbides, nitrides, sulfides)
Brittle, glassy, inelastic non-conducting (insulators)
Polymers/plastics: Covalent bonding sharing of e’s
Soft, ductile, low strength, low density thermal & electrical insulators Optically translucent or transparent.
Structural Steel (a fundamental engineered metal) in Use: The Golden Gate Bridge
Periodic Table of Elements: The Metals
Structural Ceramics
Periodic table ceramic compounds are a combination of one or more metallic elements (in light color) with one or more nonmetallic elements (in dark color).
Glasses: atomic-scale structure of (a) a ceramic (crystalline) and (b) a glass (noncrystalline)
Optical Properties of Ceramic are controlled by “Grain Structure”
MAE 224: ENGINEERING MATERIALS
1.Introduction 19
Figure 1.2 – Alumina (Al2O3) – single crystal and polycrystal
SINGLE CRYSTAL POLYCRYSTAL
POLYCRYSTAL+ PORES
Grain Structure is a function of “Solidification” processing!
Polymers are typically inexpensive and are characterized by ease of formation and adequate structural properties
Periodic table with the elements associated with commercial polymers in color
Composite Materials – oh so many combinations
Fiber Glass Composite:
The Materials Selection Process – as a part of design
1. Engineered Application will 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 shapeex: casting, sintering, vapor deposition, doping forming, joining, annealing.
Materials property chart with a view of relative materials performance. Here plots of elastic modulus and density data (on logarithmic scales) for various materials indicate that members of the different categories of structural materials tend to group together. (After M. F. Ashby, Materials Selection in Engineering Design, Pergamon Press, Inc., Elmsford, NY, 1992.)
These so-called Ashby Charts are developed for comparing candidate materials considering many design
factors
But: Properties depend on Structure (strength or hardness)
Har
dnes
s (B
HN
)
Cooling Rate (ºC/s)
100
200
300
400
500
600
0.01 0.1 1 10 100 1000
(d)
30 mm(c)
4 mm
(b)
30 mm
(a)
30 mm
And:
Processing can change structure! (see above structure vs Cooling
Rate)
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!
Electrical Properties (of Copper):
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 (°C)
-200 -100 0
Cu + 3.32 at%Ni
Cu + 2.16 at%Ni
deformed Cu + 1.12 at%Ni
1
2
3
4
5
6
Re
sist
ivity
, r
(10-8
Ohm
-m
)
0
Cu + 1.12 at%Ni
“Pure” Cu
Electrical Resistivity of Copper is affected by:• Contaminate level• Degree of deformation• Operating temperature
THERMAL Properties• Space Shuttle Tiles: --Silica fiber insulation offers low heat conduction.
• Thermal Conductivity of Copper: --It decreases when you add zinc!
Courtesy of Lockheed Aerospace Ceramics Systems, Sunnyvale, CA)
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.)
Composition (wt% Zinc)
The
rmal
Con
duct
ivity
(W
/m-K
)
400
300
200
100
00 10 20 30 40
100 mm
MAGNETIC Properties
• Magnetic Permeability vs. Composition: --Adding 3 atomic % Si makes Fe a
better recording medium!
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.
J.U. Lemke, MRS Bulletin, Vol. XV, No. 3, p. 31, 1990
• Magnetic Storage: --Recording medium is magnetized by recording head.
Magnetic FieldM
ag
net
iza
tion Fe+3%Si
Fe
DETERIORATIVE Properties
• Stress & Saltwater... --causes cracks!
Marine Corrosion, Causes, and Prevention, John Wiley and Sons, Inc., 1975.
4 mm--material: 7150-T651 Al "alloy" (Zn,Cu,Mg,Zr)
G.H. Narayanan and A.G. Miller, Boeing Commercial Airplane Company.
• Heat treatment: slows crack speed in salt water!
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.)
“held at 160ºC for 1 hr before testing”
increasing loadcra
ck s
pe
ed
(m
/s)
“as-is”
10-10
10-8
Alloy 7178 tested in saturated aqueous NaCl solution at 23ºC
Example of Materials Engineering Work – Hip Implant
With age or certain illnesses joints deteriorate. Particularly those with large loads (such as hip).
Example – Hip Implant Requirements
mechanical strength (many cycles)
good lubricity biocompatibility
Example – Hip Implant
Solution – Hip Implant 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
AcetabularCup and
Liner
Ball
Femoral Stem
Often, material selection comes down to a tradeoff of cost vs. design property
Choosing the right material for the job -- one that is the most economical and “Greenest” when life cycle usage is considered. As designers we must consider “Sustainability” in our designs and material choices Understanding the relation between
properties, structure, and processing. Recognizing new design
opportunities offered by materials selection.
Course Goal is to make you aware of the importance of Material Selection by: