The EM7 High Voltage Electron Microscope (HVEM) located at CEA Saclay has been operated since 1981. In 2008-2010 an upgrading was carried out to ensure reliable operation in future years. This microscope runs from 0.3 to 1.2 MeV and allows to form isolated defect (Frenkel Pairs) in almost all nuclear metals (Steels, Zr alloys). This well-known damage permit to directly compare experiments with simulations. Damage rates between 5.10-5 dpa/s and 5.10-3 dpa/s (in metals) can be reached. Thanks to its new Gatan CCD video camera, the Transmission Electron Microscope enable in-situ monitoring. To prevent oxidation of the samples a very good
vacuum is maintained ( 5 10-8 Torr). As others facilities, the EM7 parameters (flux, temperature, dose) can be changed easily allowing parametric studies without any activation of the samples. The samples which can be irradiated in the microscope are mostly conventional TEM thin foils, 3 mm in diameter. Recently a new single tilt heating specimen holder dedicated to Atom Probe tips was designed and fabricated.
The microscope has been mostly used so far as a tool to study
irradiation effects in materials (metallic alloys, ceramics, glasses),
in particular those of interest for nuclear applications.
Some examples of performed experiments/research topics are as follows :
CEA Saclay – DEN/DANS/DMN
Service de Recherches Métallurgiques Appliquées
91191 Gif sur Yvette
Head of laboratory :
Jean Henry + 33 1 69 08 85 08
Contact person :
Olivier TISSOT +33 1 69 08 54 45
Specific access formalities to Saclay facility :
Any person entering at Saclay for a short duration experiment (< 32 days per year) gets the status of “worker”. He/she needs to supply his host with the following information, taking into account the administrative delay (see Table below) :
First name and last name
Date and place of birth
Professional situation and address
Identity card or passport number and validity date
Information should be sent to :
A medical certificate attesting no contra-indications for working near particle accelerators will be also required.