Complex-Environment Engineering Diffractometer - CEED

0389033 - ÚJF 2013 eng C - Conference Paper (international conference)
Lukáš, Petr - Beran, Přemysl - Pilch, Jan - Strunz, Pavel - Šaroun, Jan - Šittner, Petr - Javorský, P. - Sechovský, V.
Complex-Environment Engineering Diffractometer - CEED.
2012.
[ESS S&S meeting. Berlin (DE), 19.04.2012]
Institutional support: RVO:68378271 ; RVO:61389005
Keywords : diffractometer * in-situ
Subject RIV: BM - Solid Matter Physics ; Magnetism

Design and construction of a time-of-flight (ToF) neutron powder diffractometer for material science and engineering has been proposed as a part of Czech in-kind contribution to the ESS. Presented concept of the instrument aims at in-situ experiments with materials under variety of sample environment (SE) conditions. Apart of a standard suite of neutron SE devices, the instrument should provide space and infrastructure for accommodation of specialized facilities such as high-strength pulsed magnets or a cell for dynamic thermo-mechanical testing and physical simulations of material processing (Gleeble®). Therefore, the sample area and detector systems have to be optimized with constraints imposed by SE in mind. Resulting concept (Fig.1) represents a narrow frame ToF diffractometer with 150-200 m flight path allowing to cover about 1.4-1.9 A bandwidth in a single frame. Resolution is tunable by the pulse shaping chopper and the set of adjustable diaphragms installed along the last 20-30 m of the beam path. The beam shaping optics (diaphragms and focusing guide) would allow for both high-intensity and high resolution modes, the letter providing beam characteristics suitable for simultaneous highresolution imaging across small sample area of about 25x25 mm2. Cylindrical arrangement of 2D detectors in equatorial plane covers high angle range for high-resolution, low angles for large structures and texture monitoring and +- 90 deg area for lattice strain analysis. Rotating bank on one side permits easy access to the sample area needed for users working with large sample environment devices. First MC simulations of this generic design confirm the feasibility and quantitative characteristics needed for this type of instrument: flux ~ 5·108 n/s/cm2 and resolution ~0.5% at 90o (in medium resolution mode).
Permanent Link: http://hdl.handle.net/11104/0217987