Neutron based evaluation in support of NEAMS

Abstract

The primary objective of the Advanced Non-Destructive fuel Examination (ANDE) work package is to develop capability that has the potential to accelerate insight and development of ceramic and metallic fuels. Establishing unique validation opportunities for new models is a key component of this effort. To explore opportunities a series of interactions were held with NEAMS modelers at LANL. The focus was to identify experiments that draw on the unique capabilities of neutron scattering and imaging for studies of nuclear fuel particularly in areas where experimental data can be valuable for of models validation. The neutron characterization techniques applied in the ANDE program span length scales from millimeter to micrometer to angstroms. Spatial heterogeneities of interest include cracks, pores and inclusions, crystal structure, phase composition, stoichiometry texture, chemistry and atomic thermal motion. Neutrons offer characterization opportunities that are distinct from other probes such as X-rays, electrons or protons. This report describes a variety of opportunities whereby neutron data can be related to models and lists some opportunities.

Status Report on Development of a Cask to Enable Pulsed Neutron Characterization of Irradiated Fuel

“…This cask is a key component of a pathway to characterize irradiated materials with pulsed neutrons at LANSCE described previously [14]. While in previous reports [2,3,15,16,17] these pulsed neutron techniques were described in detail and applied to un-irradiated materials, application to irradiated materials promise the highest return. These methods probe the bulk of a material and are applicable to actual fuels rather than custom-made demonstration samples and are based on energy-resolved neutron imaging (ERNI) and neutron diffraction.…”

“…Development in data analysis and instrumentation is ongoing. Besides oxide fuels, extensive characterizations of accident tolerant U-Si [27,28,29], UN/U 3 Si 5 composite fuels [15,26] and U-20Pu-10Zr transmutation fuels [16] were reported.…”