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Materials Science and Engineering
Arguably the most important discipline in engineering and
science today
Dr Greg HenessSenior Lecturer in Materials
University of Technology, SydneyB. App Sc. Materials Science
M. App Sc. Materials EngineeringPhD Materials. Engineering
Grad Cert. Higher Ed.
• Materials Scientist/Engineer
• Certified Materials Professional,
• Institute of Materials Engineering Australia
• President, State Branch IMEA
Teaching:
Materials science, composites, mechanical properties, nanomaterials
Research:
Nanomaterials (nanocomposites), composites, energy efficient materials
Me!!!
Turn them off!!! UTS Online
• Announcements on UTS Online are the main form of letting you know of changes to the program etc.
• All work for assessment will be submitted through UTS Online– Includes labs and tutes
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ASSESSMENT DETAILS
–To pass this subject, a 50% grade in the final must be achieved.
–Note you have to get 50% overall to pass.
1 Quiz 10% Practicals 25%Tutorials 15% Final Exam 50%
The importance of assessment tasks
Username Class/50 Final/50 Total GradeX1 10.6 27.7 38 Z 2 labs, no tutesX2 10.1 24.2 34 Z 4 labs, 1 tuteX3 7.7 29.7 37 Z no quizzes, 4 labs, 1 tuteX4 13.2 29.3 42 Z 4labs/1 tuteX5 14.7 28.9 44 Z 3 labs/1 tuteX6 34.1 15.9 50 X Final mark too lowX7 25.8 23.4 49 Z 50P
SAFETY
PRESCRIBED TEXT: (on reserve in the Library)
Materials Science and Engineering, 2012Compiled by Greg Heness & Mike Cortie
Compiled from 3 different texts by your lecturers specifically for this course.
Access to online resources via one of the texts by Shackelford.
Tutorial sessions will deal with examples from the book, so you can easily find related text to help you understand.
It may also prove an useful materials reference book for the future.
Co-op Bookshop on Broadway
The price at time of writing this:
$116.99 for Co-op members $125.80 for non Co-op members
TEXT:
Callister, W.D., Materials Science and Engineering An Introduction, 8th Ed., Askeland, D.R. , Fulay, P.P. Wright, W.J., The Science and Engineering of
Materials,
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Handing in Reports
Lab session Next week Next weekLab session –
Mon/TuesReport due Friday, 5pm
Answers put up Mon/Tues
RESTRICTIONS AND REGULATIONS
1. Regular attendance is mandatory at all laboratory meetings.
2.The quiz must be taken at the scheduled time and on the specified date. (set by exams branch)
3. Submission of laboratory and workshop reports and assignments is mandatory. Assigned homework must be completed on time.
4. Unless otherwise specified, homework shouldbe an individual effort.
Web-Based Tutorial Assessment Tasks
• There will be two types of tutorials presented. – The first will provide immediate feedback,
so you can gauge your progression in the course.
– The second will be of the type that will be submitted for marking. No immediate feedback will be given other than the mark you received. The week following the due date, solutions will be posted.
Note: Interdisciplinary field
• Importance to science and engineering.
• It includes elements of
– applied physics,
– chemistry and
– even biology, as well as
– chemical, mechanical, civil and electrical engineering.
4
Materials Science & Engineering The Advent of Money
• Western Turkey 600BC
• Up to this time gold was impure
– Beat the gold from the stream flat
– Mixed with salt
– Smeltered it
– First pure gold
• Once purity could be controlled it could be used as money
• Same process still used today
perhapsPERHAPS
THE MOST
IMPORTANT?
Does this seem very important?
How do we describe our history?
5
The Stone Age
• Paleolithic (40,000 to 100,000 yrs ago): Stone tools and clay pots
• Mesolithic (10,000 to 40,000 yrs ago): Extensive use of stone tools and clay, stone statues, ochre (pigment)
In general - Natural Materials
From Farside by Gary Larson
Thailand - 4500BC
Iron age
• Iron Age (1000 – 3000 yrs ago): Carburized Iron, improved forging, porcelain
Now?
The Ceramics Age(The New Stone Age!)
The Composites Age
(no longer string & glue!)
MaterialsDesign Age
-No dominant
materials
Revolutionary Forces
Source: Norman Poire, Merril Lynch
Introductionof technology
Widespread adoption
End of rapid growth phase
1771
1800
1853
1825
1913
1853
1886
20251913
1969
1939 1997
2025
1969
2081
Industrial Revolution Information Revolution
A question for you, what was invented first?
This? Or this?
• Printing press
• Silicon chip
• Paper
• Modern computer
The materials development PRECEDES the technology
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The plain and simple truth!
Technology as we know it today would not exist without materials development
The plain and simple truth!
If we don’t get it right
The plain and simple truth!
If we don’t get it right
The plain and simple truth!
Technology as we know it today would not exist without materials development
The future of our
technological society
Materials development
Every creative engineer, regardless of their
specialty, and every scientist must have a solid
grounding in the fundamentals of materials
behavior.
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The study of materials is a fascinating journey into the
relationships between structure, properties, and
performance.
•the details of atomic structure affect properties and performance..
•how processing can alter
structure
We will look inside thestructure of solids and learn how
•Materials are ‘alive’ with internal activity and tremendous driving forces.
•We’ll learn how these energies can be tamed and exploited.
Understanding SizeMaterials are...
engineered structures...not blackboxes!
Structure...has many dimensions...
Structural feature Dimension (m)
atomic bonding
missing/extra atoms
crystals (ordered atoms)
second phase particles
crystal texturing
< 10 -10
10-10
10-8-10-1
10-8-10-4
> 10-6
1
8
30mm 30m
Many material properties (particularly strength) depend on the nature of the Defects in the crystal structure.
Here we see ledges formed by the presence of defects called Screw Dislocations.
9
The surface of an alloy of platinum and rhenium (PtRh).
The light spots are Rh atoms, grey spots are Pt. The black spots arecarbon impurities.
Pt and Rh tend to cluster in small groups of the same species.
The magnification you see on the screen is over 300 million.
Efficient energy?
• Will not occur without:
– The smart use of materials
– The use of smart materials
• Will not occur
– via design alone
• Remember technology follows material development
Every creative engineer, regardless of their
specialty, and every scientist must have a solid
grounding in the fundamentals of materials
behavior.
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Relevance to your engineering profession
EPR group Mean NEPR 1 2.30 31EPR 2 2.42 27Total 2.36 58
Average Ratings for Chemistry Materials Science by EPR Group
2 = relevant3 = very relevant
Does this seem very important?
• Use the right material for the job.
• Understand the relation between structure, properties, and processing.
• Recognize new design opportunities offered by materials selection.
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Course Goals:
Controlling
1. Processing –
2. Structure –
3. Properties –
4. Performance
Realistic engineering materials:
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Structure Properties
Processing
Performance
Materials selection example
Choose material to hold a liquid:
Which one is best?
How do we
choose?
Goodness!
Realistic engineering materials:
– Trade-off between
– properties
•(what do we need or want?)
– deterioration
•(how long will it last?)
– cost
•(what’s the biggest bang for the buck?)
– Resources depletion
•(how to find new reserves, develop new environmentally-friendly materials, and increase recycling)
Materials and Their Properties
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Comparing Materials
• Materials have certain PROPERTIES which make them USEFUL
We need to be able to describe and compare the properties of a material and say why its used for a job. We use certain materials for certain jobs… Material
selection
What materials are used?
What is it used for?
Why use that
material?
Many properties will undergo change by treatments applied
Requirements
Performance & environment
selection
properties
Properties
Processing
Structure
Performance
Materials Science
Investigating the relationship between structure and properties of materials.
Materials Engineering
Designing the structure to achieve specific properties of materials.
Processing Structure Properties Performance
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
2
Structure, Processing, & PropertyH
ard
ne
ss (
BH
N)
Properties?
properties
13
properties
Chemical
Mechanical
Dimensional
Physical
• Chemical composition
– Oxide, nitride, low C steel, high C steel
• Acidic/Alkaline
– Refractory bricks
• Degradation
– Rusting, corrosion, etc.,
Chemical Physical
Mechanical
• Strength– Resistance-to- force capability
• Elasticity– Ability to recover totally from deformation
• Plasticity– Permanent deformation
• Stiffness– flexible/rigid
• Toughness– Energy absorbed during fracture
• Ductility/brittleness– Does it plastically deform before it breaks?
• Hardness– Resistance to indentation/scratching (permanent deformation)
Mechanical
Terms Mechanical
Simple definitions of the these:
StrengthDuctilityStiffnessToughnessBrittleHardnessElasticityPlasticity
Capacity to resist force or pressure
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Terms Mechanical
Simple definitions of the these:
StrengthDuctile/ BrittlePlasticityElasticityStiffnessToughnessHardness
Ductile: significant plastic deformation before failureBrittle: little or no plastic deformation before failure
Terms Mechanical
Simple definitions of the these:
StrengthDuctile/ BrittlePlasticityElasticityStiffnessToughnessHardness
Capable of being shaped or formed
Terms Mechanical
Simple definitions of the these:
StrengthDuctile/ BrittlePlasticityElasticityStiffnessToughnessHardness
Capable of recovering deformation
Terms Mechanical
Simple definitions of the these:
StrengthDuctile/ BrittlePlasticityElasticityStiffnessToughnessHardness
Resistance to elastic deformation
Terms Mechanical
Simple definitions of the these:
StrengthDuctile/ BrittlePlasticityElasticityStiffnessToughnessHardness
Ability to absorb energy before fracture
Terms Mechanical
Simple definitions of the these:
StrengthDuctile/ BrittlePlasticityElasticityStiffnessToughnessHardness
Resistance to permanent deformation and/or scratching
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Dimensional
Materials Data
Kingdom Family Class AttributesMember
• Ceramics
• Polymers
• Metals
• Composites
Steels
Cu-alloys
Al-alloys
Ti-alloys
Ni-alloys
Zn-alloys
1000
2000
3000
4000
5000
6000
7000
8000
Materials
A material record
Density
Mechanical props.
Thermal props.
Electrical props.
Optical props.
Corrosion props.
Supporting information
-- specific
-- general
Material properties Materials Classification
PE, PP, PCPA (Nylon)
Polymers,elastomers
Butyl rubberNeoprene
GFRPCFRP
CompositesKFRP
Plywood
AluminaSi‐Carbide
Ceramics,glassesSoda‐glass
Pyrex
SteelsCast ironsAl‐alloys
MetalsCu‐alloysNi‐alloysTi‐alloys
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Comparing Relationships: property bar-charts
Metals Polymers Ceramics Composites
PEEK
PP
PTFE
WC
Alumina
Glass
CFRP
GFRP
Fibreboard
Steel
Copper
Lead
Zinc
Aluminum
Structured data for ABS*
General PropertiesDensity 1.05 -1.07 Mg/m^3
Price 2.1-2.3 US $/kg
•
Mechanical PropertiesYoung's Modulus 1.1-2.9 GPa
Elastic Limit 18-50 MPa
Tensile Strength 27-55 MPa
Elongation 6-8%
Hardness - Vickers 6-15 HV
Endurance Limit 11-22 MPa
Fracture Toughness 1.2-4.2 MPa.m1/2
Thermal PropertiesMax Service Temp 350- 370 K
Thermal Expansion 70- 75 10-6/K
Specific Heat 1500 -1510 J/kg.K
Thermal Conductivity 0.17 -0.24 W/m.K
Acrylonitrile-butadiene-styrene (ABS) - (CH2-CH-C6H4)n
Electrical PropertiesConductor or insulator? Good insulator
Optical PropertiesTransparent or opaque? Opaque
Corrosion and Wear ResistanceFlammability Average
Fresh Water Good
Organic Solvents Average
Oxidation at 500C Very Poor
Sea Water Good
Strong Acid Good
Strong Alkalis Good
UV Good
Wear Poor
Weak Acid Good
Weak Alkalis Good
Structure Sensitivity/Insensitivity
• There is a general division of materials properties & is not always clear cut
• Examples:
– Structure Insensitive:
• density, stiffness
– Structure Sensitive:
• strength, ductility, some magnetic properties
• We shall address why soon
Structure Sensitivity/Insensitivity
Plastic Bag./flyer
The Range of Properties
17
Recapping………..
•4 groups of properties– Physical, – Mechanical,– Chemical,– Dimensional
•4 groups of materials– Ceramics– Metals– Polymers– Composites
• Structure sensitive properties
Recapping………..
•4 groups of properties– Physical, – Mechanical,– Chemical, – Dimensional
•4 groups of materials– Ceramics– Metals– Polymers– Composites
• Structure sensitive properties
MechanicalSimple definitions of the these:
StrengthDuctilityStiffnessToughnessDuctility/brittlenessHardnessElasticityPlasticity
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