Electron microsocpy: a powerful tool for understanding the materials


Master & doctoral Researchers


In order to keep up with the rapid evolution of industrial demands, developing innovative techniques to understand and predict the mechanical properties of materials has become a necessity for the materials science community. For example, mechanical testing combined with microstructural investigations provide engineers with the necessary information to computationally predict the mechanical performance of components. These experiments allow for the capture of the deformation mechanisms responsible for the changing microstructure.

The Transmission Electron Microscope (TEM) is one of the most well-known techniques for observing and characterizing dislocations in electron transparent thin foils (with a thickness of about 100 nm and a useful field of view of a few µm2 only). Comprehensive dislocation studies at the microscopic scale provide valuable information for extrapolating to the macroscopic mechanical response of materials and can feed advanced multiscale crystal plasticity models.

Characterization of a dislocation configuration by TEM (from Guitton et al., Philos. Mag., 2012)

Full characterization of dislocations is not limited to TEM experiments on thin foil samples. The Scanning Electron Microscope (SEM) can also access diffraction contrast on bulk materials through the phenomenon of electron channeling. Electron channeling occurs when electrons channel down the crystal planes, meaning paths where electrons can penetrate to a deeper depth before scattering. Some orientations of the crystal will cause more electrons to backscatter, resulting in orientation contrast.

Planning: (June – August 2021, online)
  • Chapter 1: basics of materials plasticity (2 hours)
  • Chapter 2: basics of physics of electron-matter interactions (3 hours)
  • Chapter 3: basics of contrast theory of crystalline defects in transmission electron microscopy (3 hours)
  • Chapter 4: contributions of the scanning electron microscopy to plasticity of materials (2 hours)