Scattering Experiments Under Uniaxial Stress of Modulated Phases

Abstract

Neutron diffraction has the potential to provide information deep below the surface of real materials. Both mechanical and thermal loading are considered. Firstly the experimental set up to realise the uniaxial stress is described. Samples of NiO and alpha-uranium were submitted to an external uniaxial stress that gives complementary information in neutrons and X-rays scattering. Reversible or displacive phase transformations take place reversibly through the transition. Finally for high spatial resolution stress it would be necessary to use high energy X-ray synchrotron facilities to optimise effectively the stress rig.