The mechanical properties of materials — how stiff or strong they are, or how easily they fracture — are of great importance for many engineering applications. My research work is to understand mechanical and physical properties of materials by performing and/or developing mechanical testing and by characterizing microstructures. The aim of these analyses is to determine suitability of materials for their field of applications.

In-situ deformation of materials

Characterizing and optimizing the mechanical properties of engineering components is one of the oldest research domains in materials science, nevertheless still very up-to-date. Mechanical tests followed by microstructural investigations provide engineers with the necessary information to computationally predict the mechanical performance of components. In-situ mechanical testing combined with diffraction (Laue and powder) and microscopy (SEM, TEM and AFM) is well known for studying the instantaneous evolution of microstructures during exposure to stress and/or temperature. Such an experiment allows capturing footprints of the deformation mechanisms responsible for the changing microstructure.

In-situ stress-strain compression (room temperature) curves coupled with neutron diffraction on Ti2AlN MAX phase. Evolution of lattice strain and relative evolution of peak width versus applied stress for different {hkil} reflections. (Guitton et al., Appl. Phys. Lett., 2014, 24; 241910)

Characterisation of microstructures

Characterization of microstructural features plays a key-role in materials engineering and materials science.  In this framework, I carry out different sort of analyses by advanced techniques including x-ray diffraction, scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. Such studies allow bringing new insight on the comprehension of fundamental deformation mechanisms of materials.

Evidence of dislocation cross-slip in Ti2AlN MAX phase deformed at 900°C. (Guitton et al., Sci. Rep., 2015, 4; 6358)

Research topics

  • Fundamental deformation mechanisms of materials.
  • Multiaxial and multiscale plasticity in metals.
  • Theory of defect contrast by electron microscopy.