Viscoelasticity links

Rod Lakes

EMA611 EMA630 BME615 BME315
  Think logarithmic
  Think logarithmic, big
  Phase delta. Stress vs. strain in sinusoidal loading. Meaning of the loss tangent.
  Spring damper model which gives single exponential relaxation.
  Single exponential relaxation E(t) on a log scale.
  Exponential and power law, linear scale.
  Exponential and power law, log scale.
  Creep vs. relaxation, direct Stieltjes construction
  Demonstrations.
  Stiffness / loss plot.

  QLV
  nonlinear superposition

Broadband viscoelastic spectroscopy (BVS)
  Instrument diagram
  slow
  fast
  Instrument
  Instrument functions
  Instrument chamber

  Resonant Ultrasound Spectroscopy (RUS)
  RUS diagram
  setup image,
  scan on scope,
  Maynard pdf of Physics Today article by Julian Maynard
  Videos of vibration modes of isotropic cylinder with length equal diameter, after T. Jaglinski torsion,
shear,
bend,
mixed bend,
flattening,
symmetric axial.
  RUS via R. Leisure
  Industrial non destructive testing
  Measure damping via RUS, pdf,
shear mode RUS pdf after Lakes.

Viscoelastic composites
  Composite Structure.
  Bounds on composite stiffness.
  Stiffness loss map, theory
  Stiff-loss shape
  Stiff-loss stiff phase

Viscoelastic Materials
  Causal mechanisms
  PMMA (Polymethy methacrylate) Viscoelasticity. A broadband spectrum.
  Indium-Tin Viscoelasticity. A broadband spectrum.
  InSn and models
  Stiffness / loss plot
  Stiffness / loss plot: new materials.
  Tissue properties.

  QLV;
experiment.

Applications
  Case study: Baby heads improper treatment.
2,
3.
  Misshapen head reshaped
  Baby helmet for head reshaping