Neutron Diffraction and Diffraction Contrast Imaging for Mapping the TRIP Effect under Load Path Change

Design, fabrication, and characterization of diffraction gratings for neutron phase contrast imaging.

We have developed a neutron phase contrast imaging method based on a grating interferometer setup. The principal constituents are two absorption gratings made of gadolinium and a phase modulating grating made of silicon. The design parameters of the setup, such as periodicity, structure heights of the gratings, and the distances between the gratings, are calculated. The fabrication of each grat...

Diffraction-contrast imaging of cold atoms

We consider the inverse problem of in-line holography, applied to minimally destructive imaging of cold atom clouds. Absorption imaging near resonance provides a simple, but destructive measurement of atom column density. Imaging off resonance greatly reduces heating, and sequential images may be taken. Under the conditions required for off-resonant imaging, the generally intractable inverse pr...

Neutron Diffraction Experiments

This ISEN award supported research toward improving the energy efficiency of actuators. The focused research objective was to develop next-generation shape memory alloy (SMA) models and structures, to demonstrate this new technology in targeted near-term applications on airplanes. Two research avenues were pursued to enable development of this new technology: 1) neutron diffraction experiments ...

Biological Neutron Diffraction

Neutron diffraction studies of water and aqueous solutions under pressure

2014 A summary is given of data obtained from neutron diffraction experiments on heavy water at elevated pressures and temperatures using three different types of pressure vessel. The pressure vessels were manufactured from (i) hard steel (EN24T), (ii) titanium-zirconium null alloy, and (iii) autofrettaged aluminium alloy (7075-T6). In cases (i) and (ii), hydraulic pressures up to 6 kbar were a...