Analytical and Experimental Methods of Non-Destructive Evaluation of Materials and Structures

  • Introduction, link with non-destructive testing, ultrasonic method, Acoustic Emission (AE) method, correlation with wave propagation and scattering.
  • Definitions, homogeneous and non-homogeneous waves, propagation, reflection, refraction, scattering. Damping-Attenuation, Wave Conversion.
  • Wave density in space and time (Wavelength, wavenumber), phase velocity.
  • Wave Equation in 3 dimensions, plane waves, equipotential surfaces, characteristic equation, dispersion, attenuation.
  • Elastic waves, isotropic homogeneous material and what types of waves can propagate, determination of phase velocities and polarization vectors.
  • Anisotropic materials, determination of propagation velocities and polarization vectors of elastic waves on anisotropic media, slowness curves.
  • Oblique incidence, Snell’s law, critical incidence angles, reflection and refraction factors between two semi-infinite media.
  • Definition of Group Velocity, differences from phase velocity.
  • Plate waves, Natural significance, types, solutions, dispersion curves, applications.