Two-dimensional X-ray diffractometer (2D-XRD).

Descriptions

We require a two-dimensional micro-diffraction instrument for our materials characterization laboratory at DCF. We intend to use this diffractometer to characterise polycrystalline and powder samples both before and after ion irradiation. The damage layer will have only a few microns of depth in the case of heavy ion irradiation, and a maximum of 300-400 microns when using the intense proton beam generated by our 5MV NEC Pelletron tandem ion accelerator. We will use the diffractometer in reflection geometry with the 2D detector, in order to characterise the ‘damaged microstructure' as a function of temperature in terms of: (1) phases present and potential amorphous fractions, (2) texture, (3) lattice strains and (4) coherent diffraction domains and micro-strains. This instrument should allow us to combine, depending on the sample characteristics, standard 2D powder diffraction with (1) micro-diffraction to study the characteristics of individual irradiated grains and/or to scan the irradiated surface layer, (2) standard reflectometry (XRR) to get information about layer thickness and roughness, (3) grazing incidence small angle scattering (GISAXS) to increase the sensitivity to the surface layer and get information about radiation-induced electron density fluctuations in the accessible SAXS length scales. The sample area to be studied with 2D-XRD will be 1-4 cm2 at the most. The University seeks bids that will provide the best resource, to deliver the best science possible, within the constraints of the EPSRC funding.