Newsletter

Subscribe to our newsletter

email

Nanoscopy and TEM

Nanoscopy and TEM

Since the very beginning, CSM has made use of Transmission Electron Microscopy to characterize the materials, and during the decades has followed the evolution of technology and the performance of this tecnique.

 

Currently, its technical equipment is represented by JEOL 3200FS-HR a 300kV transmission electron microscope (TEM) equipped with a field emission gun, in-column energy filter for electron energy loss spectrometry and energy-filtered imaging, high angle annular dark field detector for STEM Z-contrast imaging, energy-dispersive x-ray microanalysis.

It combines high resolution and 0-loss sample imaging with analytical performance, images can be recorded using a 2k x 2k CCD camera. The instrument is used primarily for studying the microstructure, dislocations, chrystallography and chemistry of materials (spectra, line scans, maps).

 

The JEOL 3200FS-HR is featured as in the following:

  • Accelerating Voltage: 300 kV
  • Electron Gun: Field Emission
  • Resolution (point to point): 0.19nm
  • Spot Size: 0.4nm
  • Single & Double tilt Be specimens holder
  • In column energy filter (EF-TEM, EELS)
  • HAADF
  • XEDS
  • SADP – NBED – CBED
  • Imaging: fluorescent screen, film plate and on axis CCD camera (2k x 2k)

 

Nanoscopy and TEM

The Transmission Electron Microscope operates by an electron beam to observe very thin specimens (~150 nm). Electrons are focused by electro-magnetic lens and the image is observed on fluorescent screen, photographic plate or by means of a CCD camera.

Electrons are accelerated by a potential of the order of hundreds KV and have wavelengths of about 0.2nm, much smaller than that one of photon (~ 400nm).

The resolving power of the same order of the wavelength of the incident radiation, is limited by the aberrations of the electro-magnetic lenses.

Microstructure analysis

By this kind of analysis is possible to quantitatively assess the effects of thermal and thermo-mechanical treatments on, morphology and spatial arrangement of the most significant nano-structural constituents:

Chemical composition

Size and shape

Position with respect to the grain dislocation density and mechanical deformation status

 

Crystallographic analysis

The arrangement of atoms in the crystal lattice is characteristic of each phase.

The knowledge of Crystallography allows to identify phases through the analysis of electronic diffraction patterns which interpretation is assisted by a software designed by CSM.

 

 “High-resolution” Microscopy

The High-resolution mode allows to observe the atomic planes disposition and spacing and to underline the defects of the crystal lattice.

In the example are shown the planes of a crystal grain (100) of an austenic steel.

 

EFTEM – Energy-Filtered TEM

By a sophisticated electromagnetic filter is possible to obtain information about the chemical composition of the constituent elements of the microstructure.

In the example is shown the map of the concentration of aluminum in particles of gamma phase-first of a nickel-based superalloy.

Energy dispersive spectrometer (XEDS) 

The EDS dispersive spectrometer (XEDS) allows to carry out qualitatively and quantitatively the chemical composition analysis of a specific point of the sample with a spatial resolution of a few nano-meters.

 

Assessment of particles size distribution

A software for automatic image analysis calculates the geometrical parameters of the particles (area, diameter, form factor, perimeter, etc..) present in a specific field and allows to perform various statistical analysis. 

Laboratory for samples preparation

The preparation of samples has a crucial role for the success of observations by TEM.

CSM’s TEM and Nanoscopy Laboratory started its activities in 1965 and during the years has gained a wide experience on the preparation of non-organic samples with particular regard to metals and alloys.

The samples are commonly prepared in shape and thin sections or duplicates, by extraction.

For observation samples in powder materials, ceramics and cross sections of multi-layer materials, such as coatings, layers of oxides, etc. can be also prepared.

© 2014 - Centro Sviluppo Materiali S.p.A. Via di Castel Romano, 100 - 00128 - Rome - ITALY
Ph. +39 06 50551 - Fax. +39 06 5055204 - Share Capital 1.050.000 Euro Fully Paid-Up
Registro Imprese di Roma CF 00477510580 R.E.A. di Roma 269973 - PI 00903541001