The laboratory is focussed on microstructural investigations of solid materials through high-resolution scanning electron microscopy (SEM microscope, Fig. 1), with:

  • in-chamber detectors for conventional observations with secondary electrons (SEI) and backscattered electrons (BEI) (Fig. 3a) for surface observations of bulk materials;
  • in-column detectors for high resolution investigations; detector dedicated to observations of thin foils through scanning transmission electron microscopy (STEM) to investigate the inner microstructure of materials (Fig.s 2a and b);
  • a system for micro-analytical semi-quantitative analysis through energy dispersive spectroscopy (EDS) with last generation LN-free SDD detector with improved energy resolution and high acquisition rate (up to 100,000 cps) for elemental maps with high spatial resolution (Fig. 3b);
  • an acquisition system of Kikuchi electron backscattered diffraction (EBSD) patterns for surface crystallographic mapping with high spatial resolution (Fig.s 4a and b).

The laboratory is outfitted also with conventional metallographic optical microscopy (OM) and X-ray Bragg-Brentano diffraction system (θ-2θ) for crystallographic characterization of polycrystalline materials and characterization of the deformation state and residual stresses of materials.

The laboratory is equipped with chemical instrumentations for specimen preparation related to the described analysis techniques.

    • Metallographic optical microscope Leitz DM RNE;
    • High resolution scanning electron microscope SU-70 Hitachi (resolution limit = 1.6 nm) with:
      • Conventional in-chamber detectors for secondary (E-T) and solid state detector for backscattered electrons;
      • High resolution in-column detectors for secondary and backscattered electrons with energy filter;
      • Scanning transmission electron detector (STEM);
      • Micro-analitical system Noran 7 by ThermoScientific Inc. for energy dispersion spectroscopy (EDS) with LN-free SDD detector;
      • Micro-analitical system Noran 7 by ThermoScientific Inc for electron back scattered diffraction (EBSD) acquisition and analysis;
    • X ray diffraction system Siemens D500;
    • Instrumentation for metallographic preparation;
    • Twin jet Tenupol by Struers for electro-polishing for thin foil preparation for STEM observations.
Fig. 1 – HR SEM microscope SU70 – Hitachi.

Fig. 2 – STEM micrographs: (a) multi-walled nanotube; (b) dislocation-precipitate interactions in stainless steel AISI 441.

Fig. 3 – (a) BEI micrograph of Ag-Cu-Si produced by rapid solidification (RS); (b) elemental map of (a).

Fig. 4 – (a) EBSD orientation map of stainless steel AISI 304 deformed at 1100°C, 10-1 1/s; (b) dislocation structure of (a).