3.11 Brief Summary of Lectures :
IMPORTANT NOTE :
Please come to lecture on time!
The most important part of the lectures is given in the first 15 minutes!
I will start lecture at exactly 5 minutes past the hour.

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Lecture Format : Handouts are given out in class which contain figures, schematics, etc. and an outline of the lecture but leaving room on each page for what is discussed in detail in class, e.g. aderivations, math problems, etc. The bare bones outlines and figures will be posted on the web as a powerpoint file the day after each lecture here : http://web.mit.edu/course/3/3.11/www/Lectures. If you miss a class, I would strongly suggest asking another student in the class to obtain the missed written notes. If you really can not find anyone in the class to obtain the missed notes from and have a valid excuse for missing class, I will copy my notes for you. The only valid excuses for missing a class include medical, personal, or job interviews for seniors.

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STRESS VERSUS STRAIN BEHAVIOR (2 weeks) :
        · Normal stress and strain
       · Shear stress and strain
(*Readings: Gere Sections : 1.1, 1.2, 1.5, 1.6, 1.7)
       · Hooke’s law and constitutive equation for elastic behaviour
(*Readings: Gere Sections : 7.5, 7.6 Also, Prof. Roylance's Summary of Constitutive Equations)
       · Composite materials
(*Readings: See Prof. Roylance's Introduction to Composite Materials)
       · Thermal strain
(*Readings: Gere Section 2.5)

TRUSSES (1 week) :
      · Member forces
      · Displacements
(*Readings: Gere Sections 2.1, 2.2 Prof. Roylance's Introduction to Trusses)
       · Strain energy and Castigliano's Theorum
(*Readings: Gere Section 2.7, 9.9)

PRESSURE VESSSELS (1 lecture) :
      · Stresses
      · Deformation: Poisson effect
(*Readings: Gere Sections 8.1, 8.2, 8.3)

TORSION OF CIRCULAR SHAFTS (2 lectures) :
      · Stresses
      · Rotational displacement
(*Readings: Gere Sections 3.1, 3.2, 3.3, 3.4, Prof. Roylance's Introduction to Torsion))

BEAM BENDING (2 weeks) (*Prof. Lorna J. Gibson Guest Lectures)
      · Shear and bending moment diagrams
      · Normal strains in beams
      · Normal stresses in beams
      · Shear stresses in rectangular beams
      · Shear stresses in webs of beams with flanges
      · Beam displacements
(*Readings: Gere all of Chapter 4, Sections 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.8, 5.9, 5.10
(* Summary of Beam Theory 1, Summary of Beam Theory 2, Summary of Beam Theory 3)

EXAM #1 : 10/17/03

TRANSFORMATION OF STRESS AND STRAIN (1 week) :
      · Equilibrium equations
(*Readings: Gere Sections 7.2, 7.3)
      · Mohr's Circle
(*Readings: Gere Section 7.4)

ELASTIC MODULI (1 week) :
      · Linear elasticity (energetic) : modeling bonding between atoms via the Lennard-Jones Potential
(*Readings: Handouts : Van Vlack,"Elements of Materials Science, Chapter 2 and Ashby MF and Jones DRH "Engineering Materials, An Introduction to their Properties and Applications" Second Edition. Butterworth Heinemann. Chapters 3 and 4)

ELASTIC MODULI (cont'd) (1 week) :
      · Nonlinear elasticity (entropic) : kinetic theory of rubber elasticity

VISCOELASTICITY (2 weeks) :
      · Molecular mechanisms
      · Hookean springs and Newtonian dashpots
           · Maxwell model for stress relaxation
           · Voigt model for creep
           · Maxwell standard linear solid
      · Time-temperature superposition

PLASTICITY AND YIELD (1 week) :
      · Dislocation basis for yielding in crystals : edge, screw, and mixed dislocations
      · Strengthening methods and plasticity in polycrystals
      · Yield in polymers : necking, crazing, shear deformation zones, strain hardening
      · Creep, mechanisms of creep, creep-resistant materials

FRACTURE MECHANICS (1 week) :
      · Statistics of fracture, definition of fracture toughness
      · Energy balance approach
      · Stress intensity approach
      · Effect of sample geometry
      · Micromechanisms of fracture

EXAM #2 : Tuesday December 16th, 2003 afternoon, RM TBA