The Neutron Imaging Instrument CONRAD—Post-Operational Review

Abstract

The neutron imaging instrument CONRAD was operated as a part of the user program of the research reactor BER-II at Helmholtz-Zentrum Berlin (HZB) from 2005 to 2020. The instrument was designed to use the neutron flux from the cold source of the reactor, transported by a curved neutron guide. The pure cold neutron spectrum provided a great advantage in the use of different neutron optical components such as focusing lenses and guides, solid-state polarizers, monochromators and phase gratings. The flexible setup of the instrument allowed for implementation of new methods including wavelength-selective, dark-field, phase-contrast and imaging with polarized neutrons. In summary, these developments helped to attract a large number of scientists and industrial customers, who were introduced to neutron imaging and subsequently contributed to the expansion of the neutron imaging community.

Investigating Hydrogen in Zirconium Alloys by Means of Neutron Imaging

“…Neutron radiography was performed with all cladding tubes, whereas tomography measurements were applied only at chosen ones, as they had had shown clear hydrogen enrichment in the neutron radiographies. The facilities ICON and BOA at PSI, the ANTARES beamline at TU Munich, and the CONRAD [39] facility at the Helmholtz Center Berlin (now out of operation) were used for the neutron imaging investigations. Pixel sizes of about 30 to 40 µm were applied.…”

“…Figure 7. Illustration of circumferentially (a) and radially (b) oriented zirconium hydrides (black) in a cladding tube [39] with a light microscopic image of a Zry-4 cladding tube sample with mainly circumferentially orientated zirconium hydrides (c).…”

Hydrogen Transport and Evolution in Ni‐MH Batteries by Neutron Imaging

“…The large neutron scattering cross section for hydrogen compared to other elements [18,19] makes neutron radiography ideal as a non-destructive tool to probe gaseous as well as condensed hydrogen containing phases in the battery without further modifications. [20] In this work, we performed neutron imaging (combination of radiography and tomography) while monitoring the SoC of the battery under operating conditions to observe the electrochemical processes in the battery and bridge the knowledge gap. The measurements reveal the hydrogenation state of the electrodes as well as the hydrogen partial pressure in the battery in real time as a function of applied potential and current.…”

Neutronen machen Wasserstofftransport und Gasbildung in Ni‐Metallhydrid‐Batterien sichtbar

“…Der große Neutronenstreuquerschnitt von Wasserstoff im Vergleich zu anderen Elementen [18,19] macht die Neutronenradiographie zu einem idealen zerstörungsfreien Werk-zeug, um sowohl gasförmige als auch kondensierte wasserstoffhaltige Phasen in der Batterie ohne weitere Modifikationen zu untersuchen. [20] In dieser Arbeit haben wir die Neutronenbildgebung (Kombination aus Radiographie und Tomographie) bei der Überwachung des SoC der Batterie unter Betriebsbedingungen durchgeführt, um die elektrochemischen Prozesse in der Batterie zu beobachten. Die Messungen zeigen den Hydrierungszustand der Elektroden sowie den Wasserstoffpartialdruck in der Batterie in Echtzeit als Funktion des angelegten Potenzials und Stroms.…”