Graduate student project started in 2017, Alexandre EMERIAULT
The goal of this internship is to study icosahedral nanostructure of Al-Pd-Mn quasicrystals under various stress and temperature conditions, in order to characterize and better understand fundamental elementary mechanisms of plasticity for this kind of alloy.
Using techniques proposed by literature, the first step consists in preparing Al-Pd-Mn samples for STM/AFM surface investigations. The objective is to find the atomic structure already observed by different research groups. The second step consists in using the third ultra-high (UHV) chamber which is now connected to the NANOPLAST device allowing to deform samples at given speed rate and at high temperature (T ≥ 700 K). STM/AFM UHV observations will be realized at different plastic deformation levels, from the beginning of plasticity in hardening plastic stage to softening range, in order to fully characterize the nanotructures generated at surface and to give new insight onto traces of dislocation glide and/or of dislocation climb which controls the plasticity of these complex materials.