Environmental cell for USANS/SANS studies with aggressive fluids at high pressures and temperatures

Abstract

The new (Ultra) Small Angle Neutron (USANS/SANS) cell provides in-situ monitoring capability of the evolving microstructure and physical properties of a wide range of natural and artificial materials. This modular, portable compact environmental cell is designed for thermal, mechanical and chemical loading measurements compatible with all neutron and X-ray-based research facilities worldwide that is fine-tuned to a specific beamline. A seamless integration of time-lapse structural information, on scales ranging from the sub-nano to the micrometre has been demonstrated in a series of USANS/SANS experiments performed on rock samples subjected to hydrostatic and uniaxial load, reactive fluid flow and elevated temperatures. The modular design of the cell allows optimisation for specific applications, ranging from cryogenic to temperatures over 500 °C, with plans for further extensions of this range in the future. Uniaxial mechanical stress up to 1000 bar, and sample surrounding fluid/gas pressure of up to 1000 bar in the constant pressure or constant flow rate mode can be applied independently to the sample during data acquisition. Due to the modular design, components such as windows, seals and pistons can be interchanged optimising the cell for use with chemically aggressive (including ultra-supercritical) fluids. This development supports research initiatives in geology, energy and minerals, resource engineering, civil engineering, material sciences, biotechnology, and medical sciences. The cell is also extendable for use in neutron diffraction and tomographic experiments.