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MLZ 308 MECHANICAL BEHAVIOUR OF MATERIALS
Week 1
Learning Outcomes,
Introduction to Mechanical Behaviours of Materials (Structure-Property Relationships, Classification
of Materials, Polycrystalline and Single Crystalline materials, General Overview of Mechanical
Properties)
Week 2
MECHANICAL PROPERTIES OF METALS
Concepts of Stress and Strain
Notation for Tension and Compression
Tension Tests and Compression Tests (ASTM Standards)
Engineering Stress (Note: Callister+Smith+Hertzberg)
Engineering Strain (Note: Callister+Smith+Hertzberg)
Shear Stress
Tensor description of stress and strain (Note: Davidge pp.19-22, Green pp. 36-44)
Mohr’s circle (Note: Green p. 34)
Elastic deformation
Demonstration of all possibilities on a figure and then focusing on elastic systems (Note: Various
books+Green p. 17)
Stress-Strain Behaviour
Hooke’s Law
3-D Hooke’s Law (Note: Green pp. 44-47)
Modulus of elasticity (Note: Callister+Askeland)
Week 3
Relationship between modulus of elasticity and structure (i.e., atomic bonding and crystal structureanisotropic behaviour)
Effect of temperature on modulus of elasticity (Callister-7th edition, p. 139)
Elongation (Elastic) Computation
Anelasticity (time dependent elastic behaviour) (Note: Callister pp.113-4+Green p. 51)
Elastic Properties of Materials (Elastic constants besides modulus of elasticity, Poisson’s ratio, shear
modulus and bulk modulus (Note: Callister+Davidge pp. 20-25+Green pp. 23-24)
Computation of Load to Produce Specified Diameter Change
Week 4
Plastic Deformation
Stress-Strain Curve for a Plastically Deforming System
Tensile Properties (yielding, proportional limit, yield strength, tensile strength)
Mechanical Property Determinations from Stress-Strain Plot
Ductility
Resilience
Toughness (engineering property not a materials property)
True Stress and True Strain (Note: Callister+Askeland+Smith+Hertzberg)
Ductility and True Stress at Fracture Computations
Calculation of Strain Hardening Exponent
Week 5
Elastic Recovery After Plastic Deformation
Compressive, Shear and Torsional Deformation
Hardness
Rockwell Hardness Tests
Knoop and Vickers Microindentation Hardness Tests (ASTM Standards)
Correlation Between Hardness and Tensile Strength
Property Variability and Design/Safety Factors
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Variability of Material Properties
Computation of Average and Standard Deviation Values
Average and Standard Deviation Computations
Design/Safety Factors (design stress, safe (working) stress)
Design Example
Week 6
Midterm Exam I
Week 7
DISLOCATIONS AND STRENGTHENING MECHANISMS
Dislocations and Plastic Deformation
Slip,
Dislocation Density and Characteristics of Dislocations
Slip plane + Slip direction: Slip system
Slip in Single Crystals (resolved shear stress, critical resolved shear stress)
Resolved Shear Stress and Stress to Initiate Yielding Computations
Slip in Ceramics, Geometrical Aspects of Dislocations (Note: Green pp. 17-18, Green pp. 179-183,
Davidge pp. 51-63)
Plastic Deformation of Polycrystalline Materials
Deformation by Twinning
Week 8
Mechanisms of strengthening in Metals (Note: Callister+Askeland)
Strengthening by Grain Size Reduction
Hall-Petch Equation
Solid-Solution Strengthening
Strain Hardening (cold working, per cent cold work)
Tensile Strength and Ductility Determinations for Cold-Worked Copper
Relationship between degree of cold worked and grain size after recovery, recrystallization and
grain growth
Week 9
Mechanical Behaviour of Ceramics
STRUCTURES AND PROPERTIES OF CERAMICS
Ceramic structures and imperfections in Ceramics (Summary)
Mechanical Properties
Brittle fracture of Ceramics (Note: Callister+Askeland)
Stress-strain behaviour
General response to stress, temperature dependence of strength (Note: Davidge p. 15-17)
Mechanisms of plastic deformation
Fracture or flow (Note: Davidge pp. 28-30)
Miscellaneous mechanical considerations
Measurements of mechanical properties, solutions of example problems
Week 10
Test methods
Examples from Ceramic Systems and effects of test geometries on measurements (three point
bending, 4-point bending, Young’s modulus, indentation, etc.)
The fracture strength of ceramics (Note: Davidge pp. 75-103)
Weibull Modulus (Note: Callister+Davidge pp. 132-139, Green pp. 286-291)
Thermal expansion (Note: Callister-3rd edition, p. 646)
Thermal Stresses (Note: Callister-3rd edition, pp. 651-653)
Stress distributions and the effects of thermal expansion mismatch (e.g. the difference of thermal
expansion coefficients) (Note: Davidge pp. 86-87)
Thermal stress and thermal shock parameters, solutions of example problems
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Week 11
Mechanical Behaviour of Polymers
POLYMER STRUCTURES (Summary)
CHARACTERISTICS, APPLICATIONS, AND PROCESSING OF POLYMERS
Mechanical and thermomechanical characteristics
Stress-strain behaviour
Deformation of semicrystalline polymers
Melting and glass transition phenomena
Thermoplastic and thermosetting polymers
Viscoelasticity
Deformation of elastomers
Fracture of polymers
Miscellaneous characteristics
Polymer applications and processing (Summary)
Elastomers: vulcanization and elastomeric types
Mechanical Behaviour of Composites
COMPOSITES
Particle-reinforced composites (Note: Callister+Davidge pp. 24-26+Hertzberg)
Large-particle composites
Dispersion-strengthened composites
Fiber-reinforced composites (Note: Callister+Davidge pp. 24-26+Hertzberg)
Influence of fiber length
Influence of fiber orientation and concentration
Structural composites (Summary)
Week 12
Midterm Exam II
Week 13
FAILURE (Note: Callister+Askeland+Hertzberg)
Fracture
Fundamentals of fracture (Note: Callister+Davidge pp. 31-50)
Ductile fracture
Brittle fracture
Principles of fracture mechanics: stress concentration, Griffith theory of brittle fracture, stress
analysis of cracks, fracture toughness, design using fracture mechanics (Note: Callister+Hertzberg)
Impact fracture testing: impact testing techniques, ductile-to-brittle transition
Thermal stresses, thermal behaviour and fracture in ceramics (Note: Davidge pp. 118-131)
Week 14
Fatigue
Cyclic stresses
The S-N curve
Crack initiation and propagation, Crack propagation rate
Factors that affect fatigue life
Environmental effects
Creep
Generalized creep behaviour
Stress and temperature effects
Creep mechanisms: Nabarro-Herring creep, Coble creep, the flow stress and plastic flow (Note:
Davidge pp. 64-74)
Data extrapolation methods
Alloys for high-temperature use
Week 15
Final Exam