On line Raman spectroscopy
Raman spectroscopy is an efficient technique for studying the evolution of the microstructure of materials under irradiation. It allows to determine the phases present before and formed after irradiation, to outline the stress induced by irradiation, to evidence phase transition under irradiation and to monitor the damage build-up. For that purpose, a confocal Raman spectrometer has been installed at JANNuS-Saclay in 2013, which allows characterizing a variety of materials of nuclear interest. The Raman spectrometer is a Renishaw Invia Reflex device equipped with a Leica DM2500 microscope with 5 objectives (x5, x20, x50, x50L and x100). A 100 mW, frequency-doubled Nd:YAG (532 nm) laser is used as the excitation source. Complementary He:Ne (633 nm) laser is available for ex situ characterization.
In March 2014, the spectrometer has been coupled to the triple beam chamber. The main objective of the on line Raman spectrometry is to monitor in real time the evolution of the damage induced by single-, dual- or triple beam irradiations.
For in situ measurements, a dedicated device has been connected to the Raman spectrometer and to the triple beam chamber.