High-Resolution Neutron Diffractometer Based on the IN-06 Pulsed Neutron Source at the Institute for Nuclear Research, Russian Academy of Sciences

Abstract

A high-resolution neutron diffractometer has been fabricated on the basis of an IN-06 pulsed neutron source at the Institute for Nuclear Research, Russian Academy of Sciences. The diffractometer incorporates two blocks of detectors with helium neutron counters and time-of-flight (TOF) focusing at scattering angles of 156°–165°. A block of new-type high-efficiency scintillation detectors of thermal neutrons based on a ZnS(Ag)/LiF scintillator and silicon photomultipliers with TOF focusing is developed and tested. Test measurements are performed, and the diffractometer resolution is estimated. The diffraction pattern of nonmagnetic NiCrAl alloy is measured and used to determine the phase composition by means of the Rietveld method. It is demonstrated that the given setup can be applied to phase analysis.