ME6501 MECHANICAL BEHAVIOUR OF MATERIALS

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ME6501 MECHANICAL BEHAVIOUR OF MATERIALS

• Module I (10 hours)
• Concepts of crystals, Plastic deformation by slip
  and twinning, Slip systems in FCC, BCC and HCP
  lattices, Critical resolved shear stress for
  slip, Theoretical shear strength of solids,
  Stacking faults and deformation bands.
  Observation of dislocations, Climb and cross
  slip, Dislocations in FCC and HCP lattice,
  Partial dislocations, Stress fields and energies
  of dislocations, Forces between dislocations,
  Interaction of dislocations, Dislocation sources
  and their multiplications.

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• Module II (10 hours)
• Strengthening from grain boundaries, Grain size
  measurements, Yield point phenomenon, Strain
  aging, Solid solution strengthening,
  Strengthening from fine particles, Fiber
  strengthening, Cold working and strain hardening,
  Annealing of cold worked metal. Fracture in
  metals, Griffith theory of brittle fracture,
  Metallographic aspects of fracture, Fractography,
  Dislocation theories of brittle fracture, Ductile
  fracture, Notch effects, Strain energy release
  rate in fracture, Fracture toughness and design.

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• Module III (10 hours)
• Fatigue of metals, The S-N curve, Low cycle
  fatigue, Fatigue crack propagation, Effect of
  stress concentration on fatigue, Size effect,
  Surface effects and fatigue, Fatigue under
  combined stresses, Effects of metallurgical
  variables and fatigue, Corrosion fatigue, Design
  for fatigue, Effect of temperature on fatigue.
  Creep and stress rupture, Creep curve, Stress
  rupture test, Mechanism of creep deformation,
  Activation energy for steady state creep,
  Superplasticity, Fracture at elevated
  temperature, Creep resistant alloys, Creep under
  combined stresses.

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• Module IV (10 hours)
• Tension test, Stress-strain curves, Instability
  in tension, Ductility measurement, Effect of
  strain rate, temperature and testing machine on
  flow properties, Stress relaxation testing, Notch
  tensile test, Anisotropy of tensile properties.
  Hardness test, Brinnel, Rockwell and Vickers
  hardness, flow of metal under the indenter,
  relationship between hardness and flow curve,
  micro hardness testing, Hardness at elevated
  temperatures.

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• Text Book Dieter M. George, Mechanical
  Metallurgy, McGraw- Hill Inc., 2001.
• References
• 1. Deformation and fracture mechanics, Richard W
  Hertzberg John Wiley Sons
• 2. Mechanical behaviour of Materials, Frank A
  McCLINOCK and ALI S ARGON
• 3. Physical Metallurgy Principles, Reed Hill and
  Robert E, East West Press
• 4. Structure and properties of Materials, Hyden
  W. M. Vol. 3, McGraw Hill
• 5. Plastic deformation of Metals , Honeycombe,
  Arnold Press.

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• An understanding of mechanical behavior is
  important to both the development of new
  materials and the selection of appropriate
  materials for many applications. 
• This is best investigated and understood by
  integrating solid mechanics with the
  microstructural basis of deformation and
  fracture. 
• The course is intended as a formal basis for
  students to pursue an integrated approach to the
  mechanical behavior of material. 

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Text Mechanical Behaviour of materials- Thomas
Courtney (2nd Ed.McGraw Hill)References1.
Mechanical Behaviour of Materials- Mark Andrew
Meyers K.K. Chawla (Prentice Hall)2.
Mechanical Metallurgy- George Dieter (McGraw
Hill)3. Materials Science and
Engineering-William Callister,Jr. (Wiley)4.
Engineering Materials,1, Michael Ashby and David
Jones (Pergamon)5. Deformation and Fracture
Mechanics of Engineering Materials, Richard W.
Hertzberg, (Wiley Sons, NY)
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Key Phrases - Statistically Improbable Phrases
(SIPs) transient creep model,
maximum shear criterion, shear stress yield criter
ion, engineering fracture strength,
making life estimates, nominal stress amplitude,
multistage spring, nonzero mean stress,
environmental crack growth, notched member,
creep elements, standard compact specimen,
maximum normal stress criterion,
short fatigue lives, principal normal stresses,
frictional sliders, uniaxial curve,
deformation plasticity theory, current crack lengt
h, true fracture strength, plasticity limitations,
elastic stress concentration factor,
shear stress criterion, elliptical hysteresis,
principal normal strains
Inside This Book First
SentenceDesigners of machines, vehicles, and
structures must achieve acceptable levels of
performance and economy, while at the same time
striving to guarantee that the item is both safe
and durable
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Provides comprehensive treatment of the
mechanical behavior of materials within a
balanced mechanics-materials approach. Covering
a range of materials, including metals, polymers,
ceramics, and composites, this book presents the
properties of materials while addressing the
principal ideas behind theories of mechanical
behavior. It includes broad treatment of flow
and fracture criteria. It presents various
mechanisms for tailoring the strength and
toughness of materials. It also provides
references and a list of suggested readings in
each chapter.
A valuable reference book on the mechanical
behavior of materials for all practicing
Mechanical and Materials Engineers.
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• This text differs from others because the
  treatment of plasticity has greater emphasis on
  the interrelationship of the flow, effective
  strain and effective stress and their use in
  conjunction with yield criteria to solve
  problems.
• The treatment of defects is new. Schmids law is
  generalized for complex stress states. Its use
  with strains allows for prediction of R-values
  for textures.
• Another feature is the treatment of lattice
  rotations and how they lead to deformation
  textures.
• The chapter on fracture mechanics includes
  coverage of Gurney's approach. Much of the
  analysis of particulate composites is new. Few
  texts include anything on metal forming.
• Includes numerous examples and
  end-of-chapter problems
•  Emphasizes quantitative problem solving
•  Briefer, less expensive, and more modern than
  competition

This textbook is for courses on Mechanical
Behavior of Materials taught in departments of
Mechanical Engineering and Materials Science.
The text includes numerous examples and problems
for student practice. The book emphasizes
quantitative problem solving. End of the chapter
notes are included to increase students'
interest.
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MATERIALS IN TODAYS WORLD

• Introduces the field of materials science in a
  format suitable for non-engineering students.
  Materials and their properties are examined in
  the context of their use in everyday objects
  including sports equipment, automobiles,
  aircraft, display screens, compact disc players,
  hip-replacements, etc. The role materials have
  played and will continue to play in shaping
  society will be discussed. Examples and
  demonstrations will be the major component in
  this course. Course is intended as an elective
  for non-engineering students. Course may not be
  taken as a technical elective by students in the
  College of Engineering. 3 hours.

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BEHAVIOUR

• How to study?

Eg Human Behaviour- The potential and expressed
capacity for physical, mental, and social
activity during the phases of human life. Human
beings, like other animal species, have a typical
life course that consists of successive phases of
growth, each of which is characterized by a
distinct set of physical, physiological, and
behavioral features.
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Class 2

• Introducing students to the Foundry Section of
  Central Workshop
• Primary ideas on moulding- familiarise with the
  sequence, importance of ramming, gating design,
  sand properties, pattern materials and pouring

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Class3

• For self study
• Crystals FCC,BCC,HCP
• About Miller Indices- one family
• Directions as and
  lt gt
• Planes as ( ) and
  
• Atomic Packing Factor
• Defects- Point, Line, Surface, Volume
• Deformations/ Dislocations Edge, Screw
• Slip Phenomenon

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• About Tension Test Its Importance-
• Engineering Stress and True stress
• Elastic Region, Proportionality Limit,
  Yielding, Strain hardening, Necking
• Loading and unloading in elastic limit
• Yield Stress, Ultimate Stress, Fracture Stress
• Examples- transmission tower/ casting

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MECHANICAL BEHAVIOUR,
TESTING
AND
MANUFACTURING PROPERTIES OF MATERIALS
National Institute of Technology Calicut
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RELATIVE MECHANICAL PROPERTIES OF MATERIALS AT
ROOM TEMPERATURE
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STRENGTH

• Glass Fibers
• Graphite Fibers
• Kevlar Fibers
• Carbides
• Molybdenum
• Steels
• Tantalum
• Titanium
• Copper
• Reinforced Plastics
• Termoplastics
• Lead

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HARDNESS

• Diamond
• Cubic Boron Nitride
• Carbides
• Hardened Steels
• Titanium
• Cast Irons
• Copper
• Thermosets
• Magnesium
• Thermosets
• Thermoplastics
• Lead
• Rubbers

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TOUGHNESS

• Ductile materials
• Reinforced Plastics
• Thermoplastics
• Wood
• Thermosets
• Ceramics
• Glass
• Ceramics
• Reinforced Plastics
• Thermoplastics
• Tin
• Thermoplastics

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STIFFNESS

• Diamond
• Carbides
• Tungsten
• Steel
• Copper
• Titanium
• Aluminium
• Tantalum
• Plastics
• Wood
• Thermosets

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STRENGTH/DENSITY

• Reinforced Plastics
• Titanium
• Steel
• Aluminium
• Magnesium
• Beryllium
• Copper

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Fig.1
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