The 16th December 2024, will mark 40 years since neutrons were first produced at the ISIS pulsed neutron and muon facility at STFC Rutherford Appleton Laboratory in Oxfordshire, UK. Since that date, the facility has operated several types of targets and added muon capabilities and the second target station (TS2). This talk will provide a brief history of the targets employed, touch on some of...
The Facility for Rare Isotope Beams (FRIB) is a scientific user facility for nuclear science. FRIB’s superconducting radio frequency (SRF) linear heavy-ion accelerator can accelerate all the ions up to uranium to energies above 200 MeV/u. The design beam power is 400 kW, which, once achieved, will extend the heavy-ion accelerator power frontier by more than one order of magnitude. FRIB...
The Second Target Station (STS) project is an expansion to the existing Spallation Neutron Source (SNS) in Oak Ridge, TN. The project is at the end of the preliminary design phase. STS seeks to provide world leading peak cold neutron brightness to a suite of new instruments, eight of which are included in the project scope. SNS is currently in the final stages of the Proton Power Upgrade...
The China Spallation Neutron Source (CSNS) marked its inaugural operational milestone by generating a neutron beam in August 2017. In August 2018, it passed national acceptance and officially started operation. The CSNS target station is distinguished by its stationary tungsten target and three distinct moderators: Decoupled and Poisoned Hydrogen Moderator (DPHM), Coupled Hydrogen Moderator...
The Proton Beam Window (PBW) of the target station is one of the key equipment in China Spallation Neutron Source (CSNS). The PBW 1 has been running stably since2018. The PBW 2 has been completed and is planned to replace PBW 1during the CSNS summer maintenance in 2024.
This will be the first time to replace the PBW at CSNS. As an extremely important task, it poses great difficulty, tight...
Oxide dispersed strengthened (ODS) ferritic/martensitic steels have been extensively studied in various fusion and fission materials R&D programs. Due to their high strength at high temperatures, ODS steels are tentative structural materials in ADS. The objective of this study is to determine irradiation-induced evolution of nano-sized clusters in ODS steels. The selected ODS steels are...
As part of the CSNS-II Project, a new design of moderator and reflector plug will be installed at CSNS-II target station.
As the proton beam power will be upgraded from 100KW to 500KW, the structure and the manufacturing technology of the reflector will be optimized to accommodate the higher thermal deposition. The material 6061-T6, which has stronger resistance to stress corrosion, will be...
Due to its high density, high melting point, and high thermal conductivity, W is used as a solid target material for scattering neutron sources. However, because of the poor corrosion resistance of W, it is necessary to coating a good corrosion-resistant layer to ensure the long-term use of the target material, Ta metal is a good choice and both have good applications in ISIS and CSNS.
CSNS...
The ISIS Facility uses a Tantalum clad Tungsten target in order to produce neutrons which facilitates unique and innovative research. The properties required for a material to qualify as a potential target material are strict, resulting in scarce options. Often these materials are very expensive due to their rarity and are also very difficult to work with from a machining and manufacture...
The Second Target Station will be a world-leading neutron facility with cold neutron brightness an order of magnitude better than the Oak Ridge National Laboratory (ORNL) Spallation Neutron Source First Target Station. This facility aims to produce world-class brightness neutrons to advance fundamental science.
A rotating 1.2m diameter target disk of 58mm thick Tungsten has been selected...
The target assembly for the Second Target Station (STS) at Oak Ridge National Laboratory is working towards final design approval in late 2025, and R&D continues to focus on the manufacturing of the target segment. The novel design of the target segment and unique combination of materials (tungsten, tantalum, copper, and Inconel) has driven the process development towards solid state bonding...
CERN’s upcoming Beam Dump Facility (BDF) will host a new high-Z production target. The device will act as a beam dump to safely absorb 356kW of the 400 GeV/c proton beam delivered by the Super Proton Synchrotron (SPS). At the same time, it will generate a large number of high energy particle collisions in an attempt to produce hidden sector particles for the Search for Hidden Particles (SHiP)...
The Second Target Station (STS) project at Oak Ridge National Laboratory (ORNL) has entered preliminary design review activities with an innovative edge-cooled spallation target. The tungsten/tantalum laminate spallation block is clad in copper and contained inside a thick Inconel shroud. The shroud provides structural support. It also provides thermal management by flowing water through...
The SINQ Target Irradiation Program (STIP) is one of the crucial research projects performed by the Paul Scherrer Institute (PSI). The seventh experiment of the SINQ Target Irradiation Program (STIP-VII) was conducted in SINQ Target 10 during 2013 and 2014 and the total proton charge received by the target is 11.7 Ah. A radiation damage assessment was performed by using the Monte Carlo...
The nuclear and engineering design of the target is critical for optimizing the performance and efficiency of neutron sources. This study presents a Monte Carlo-driven analysis, conducted with the FLUKA code, of the currently operating ISIS-TS1 target and several derived notional designs. The analysis aims to quantify the impact of key nuclear parameters—such as proton range and the neutron...
Due to its profound effects on the microstructure, void swelling and embrittlement of structural materials, the transmutation gas production of hydrogen and helium is an important metric in evaluating radiation damage on structural materials in a spallation facility. A systemic measurement of gas productions at the proton beam window (PBW) and mercury target vessel at SNS is underway. ...
As part of the ISIS TS1 Project, a new design of spallation target was installed on the first target station (TS1), which has now been operating for almost a year. Detailed Finite Element Analysis (FEA) simulations were carried out, and compared to measured operating data. FEA has also been used to investigate unexpected observations on some target plates. Attempts were made to measure...
During 2021–2022, a new style of multi-plate tantalum-clad tungsten spallation-neutron-producing target was installed in Target Station 1 of the ISIS Spallation Neutron and Muon Source. It is therefore of relevance for investigations to be made into the thermal and structural performance of the irradiated target. Some challenges of deducing target performance parameters from measurements...
Conceptual design studies are now underway for ISIS-II, the successor to the UK’s pulsed neutron and muon source. Appropriate target technologies must be selected for each of the two proposed neutron target stations, to achieve a balance between neutronic performance and engineering reliability.
This talk will present the status of preliminary designs for both stationary and rotating target...
The Facility for Rare Isotope Beams (FRIB) is a high-power heavy ion accelerator facility at Michigan State University completed in 2022. Its driver linac is designed to accelerate all stable ions to energies above 200 MeV/u with beam power of up to 400 kW. Currently, FRIB is operating at 10 kW, delivering multiple primary beam species. The beam dump absorbs approximately 75% of the primary...
In developing a high-power water-cooled tungsten target for spallation neutron production, one of the important factors that limits the beam power on the target is decay heat driven temperature rise in tungsten in loss of coolant accidents. When tungsten is exposed to water vapor, tungsten oxides formed in steam is known to become volatile at above 800 oC causing radiological hazards with a...
At the Materials and Life Science Experimental Facility (MLF) in J-PARC, liquid mercury target for the pulsed spallation neutron source is in operation. A target vessel made of SS316L is damaged by pressure wave induced cavitation in mercury in addition to the 3 GeV proton and neutron irradiation. We are improving the target vessel to mitigate the cavitation erosion and gradually ramping-up...
Cavitation-induced erosion patterns on the mercury-facing surfaces of Spallation Neutron Source (SNS) mercury target vessels were simulated using a newly developed parameter called the maximum bubble size. Explicit dynamic finite element simulations of the target vessels’ structural response to beam pulses were performed. The cavitation bubble growth was calculated using a user defined...
The FCCee is a proposed 90-km electron-positron collider to be developed at CERN, intended to succeed the LHC.
During its operation, the FCCee will generate high-energy photon beams on both sides of the experimental insertions with an anticipated power of up to 500-600 kW in the 45.6 GeV, ~1.4 A operating phase. Photon energies will average between 2 to 63 MeV, with higher energy tails...
During a series of fuel assembly (FA) tests at the refurbished MEXICO facility at SCK CEN, extensive research was conducted to evaluate the material behavior and performance of heavy liquid metal (HLM)-cooled wire-wrapped fuel assemblies. The primary objective was to assess long-term material compatibility such as corrosion resistance, and thermal-hydraulic behavior under representative...
SCK CEN conducts an extensive experimental program within the MYRRHA and SFR-SMR R&D programs to characterize candidate structural materials for their application in heavy liquid metals. Main challenges lie here in the qualification of candidate materials for a variety of environmental parameters of the liquid metal system, i.e.: temperature; flow velocity; liquid metal chemistry with respect...
Liquid lead (Pb) is candidate coolant of accelerator driven systems, fast reactors and fusion reactors. However, the chemical compatibility of liquid Pb with structural materials is one of the important issues. The flow of electrons and ions in the liquid metal components may result in electrical current flow. The electrical current flow in a liquid metal pool can promote a mass transport...
Liquid lead bismuth eutectic (LBE) is a candidate target material for accelerator driven systems. The chemical compatibility of liquid LBE with structural materials is one of the important issues to be addressed. FeCrAl alloys are candidate structural materials since they can form Al-rich oxide layers on their surface which can function as an anti-corrosion barrier in liquid metals. The...
Ferritic/martensitic (FM) steels have been selected as structural materials for applications in liquid metal spallation targets, such as the MEGAPIE (megawatt pilot experiment) target, and in the future accelerator driven systems (ADSs). Liquid lead–bismuth eutectic (LBE) is a candidate target and coolant material for such systems. Apart from the serious degradation of the mechanical...
The Beam Dump Facility (BDF) and the SHiP experiment [1] have been selected to investigate hidden sector physics at CERN’s ECN3 experimental cavern starting in 2030. To produce feebly interacting particles via a fixed target impacted by 400 GeV protons from CERN’s Super Proton Synchrotron (SPS), the design of this target must safely absorb up to 356 kW of beam power [2]. With the initiation of...
The neutron time-of-flight (n_TOF) facility at the European Laboratory for Particle Physics (CERN) functions as a pulsed white-spectrum neutron spallation source. The facility's target, composed of pure lead, is impacted by a high-intensity 20 GeV/c pulsed proton beam. The facility enables the study of neutron-nucleus interactions across a wide spectrum of neutron kinetic energies, ranging...
Irradiation experiments (STIP) in the targets of Swiss spallation neutron source (SINQ) at the Paul Scherrer Institute were started in 1998. More than nine thousand specimens of various Fe-, Ni-, Al-, Zr-, and W-alloys etc. were irradiated in a wide range of irradiation dose 2-30 dpa (in Fe) and temperature of 80-550 °C, with 20-100 appm He/dpa and 200-400 ape H/dpa depending on the materials...
Ni-based alloys have been widely utilized as proton beam window (PBW) materials in existing spallation neutron sources and are potential materials for advanced generation IV reactors like molten salt reactors. However, the radiation-induced loss of ductility is still a concern, and the post-irradiation examination between different heat treatment methods is limited. This study aims to...
The microstructure and mechanical properties of components in high-dose environments are altered during operation, which typically result in a loss of ductility and fracture toughness. The decrease in ductility limits the useful component lifetime due to concerns of fracture during operation. The useful lifetimes of components are established by reviewing previous results from...
Simultaneous high-energy proton and neutron irradiation induce microstructural and mechanical responses in structural materials that are unique from irradiation with fission/fusion neutrons or accelerator-based ion beams. The target module and proton beam window (PBW) at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) are irradiated in these unique environments...
The technological challenge presented by the conceptual future ADANES is the inability of current materials and components to withstand the harsh nuclear environment. Continue long-running program was performed to pursue development of low activation structural materials, with the greatest effort directed at the SIMP steels. Recent progress on the irradiation respondence of candidate...
Ferrite/martensite (F/M) steels containing 9-12% chromium are considered as one of the most competitive candidate materials for advanced nuclear energy systems due to its excellent properties such as resistance to irradiation swelling, high thermal conductivity and low thermal expansion coefficient. SIMP steel is a novel F/M steel with about 10.24%Cr and 1.2%Si specially developed for the...
Ferritic/Martensitic (F/M) steels have become the lead material for a number of applications in extreme neutron and ion irradiation environments due to their robust resistance to irradiation effects and, in some cases, low activation. In the range from ~400 to 650°C, these materials exhibit low or no swelling in fission irradiation environments while maintaining excellent mechanical...
Among the PIE results of samples irradiated in STIP, the results of hydrogen and its isotopes release measurements are very interesting but less understood. Unlike helium, the actual hydrogen concentration of an irradiated specimen cannot be well predicted without measurement, as it strongly depends on the irradiation temperature and the irradiation environment of the specimens. In most cases,...
Nuclear-grade graphite is often used as target materials in a particle accelerator; it is also used as moderator and structural materials in nuclear fission reactor cores in the UK as well as in some GenIV reactor designs. This work will provide an overview of the types of graphite materials used in these applications and will detail the differences in their microstructure and...
High-Entropy Alloys are a class of novel material that can offer improved resistance to beam-induced radiation damage and thermal shock. Development of these new alloys to serve as beam windows in multi-megawatt accelerator target applications is ongoing at Fermilab. Currently we are investigating AlCoCrMnTiV alloy systems of 4-6 components for service as beam windows; these compositions are...
The Facility for Rare Isotope Beams (FRIB) is a scientific user facility for nuclear science. FRIB’s superconducting radio frequency (SRF) linear heavy-ion accelerator can accelerate all the ions up to uranium to energies above 200 MeV/u. The design beam power is 400 kW, which, once achieved, will extend the heavy-ion accelerator power frontier by more than one order of magnitude. FRIB...
The remote handling system is an important part of the target station and an important guarantee for the safe, stable and efficient operation of the China Spallation Neutron Source (CSNS) facility. Since CSNS formal operation began in 2018, the remote handling system has generally been operating well and a significant amount of remote handling operations have been successfully completed for...
The CSNS target operates in a composite environment of high-energy protons 1.6GeV and fast neutrons meV~GeV, and the evaluation of its operating status is crucial. In order to study the irradiation damage of the target, especially to provide more data for power upgrade, the CSNS target station PIE team has developed a small sample teleoperation preparation and mechanical properties testing...
JAEA has been developing accelerator-driven systems (ADS) for nuclear transmutation to reduce the volume and hazardousness of high-level radioactive waste generated by nuclear power plants. In order to prepare the material irradiation database necessary for the design of ADS and to study the irradiation effects of candidate structural materials for ADS in liquid lead-bismuth eutectic (LBE)...
In this talk, we will be presenting our capacities at the University of Birmingham for alloy development, manufacturing, testing and irradiation. Examples will be given on additive manufacturing of Cu/Cu alloys and W, in situ mechanical testing of steels, and irradiation tests using the cyclotron.
Positron annihilation lifetime spectroscopy (PALS) has been used to improve the understanding and prediction of early-stage helium-assisted radiation aging of structural materials. The present study integrates a unique high-energy helium ion irradiation experiment with spallation target irradiation experiments, offering experimental PALS data that reveal the microstructure and a wide range of...
The COherent Muon to Electron Transition (COMET) project is at operation of phase-α in J-PARC Hadron experimental facility. The project objective is to explore the lepton flavor violation process by searching the neutrino-less conversion of muons into electrons. In the beam line, the muon transport solenoids are composed of superconducting magnets which are kept cool by liquid Helium (LHe)....
Tungsten is used as a proton-accelerator-target material. However, a significant amount of helium is produced through spallation process under high-energy proton irradiation, compared to nuclear fission and fusion materials. The produced helium forms bubbles at grain boundaries with increasing temperature, leading to fatal embrittlement of the material. Recently, it has been reported that...
For a higher power neutron or muon source, a flowing granular target would offer superior thermal performance and enable a greater particle yield than a monolithic target. However, the flow of tungsten would necessitate solid particle impingement erosion conditions to occur. Previous work at RAL to produce a pilot plant conveying granular tungsten resulted in severe erosion of stainless-steel...
NUMERICAL MODELING OF HIDDEN DAMAGE ACCUMULATION DUE TO RADIATION EXPOSURE AND HYDROGEN EMBRITTLEMENT
Dmytro Breslavsky1, Galyna Tolstolutska2, Sergiy Karpov2
1 National Technical University “Kharkiv Polytechnic Institute”, Kharkiv, Ukraine
2National Science Center “Kharkov Institute of Physics and Technology”, Kharkiv, Ukraine
Email: g.d.t@kipt.khakov.ua
Hydrogen is generated by...
Tungsten is a key material for both nuclear fusion and as a spallation target for neutron sources. In nuclear fusion, W is being considered for heat divertors thanks to its good thermal conductivity, resistance to irradiation damage, and high melting temperature. Furthermore, due to its high density and atomic mass, W is an excellent material as a target for neutron sources. In both settings,...
Accelerator Driven sub-critical System (ADS) has been considered as a powerful technology for transmuting long-lived nuclides and minor actinides (MAs) [1]. In these systems, a spallation target located inside a sub-critical fast reactor core provides the external source neutrons to drive the operation of the ADS. The neutrons are produced via spallation reaction of high power proton beams...
The target station converts high energy (1.6GeV,62.5µA) protons into lower-energy (< 1 eV), short-pulsed neutron beams optimized for the neutron scattering instruments. The interaction between the pulsed high-energy proton beam with the light water-cooling tungsten target produces the fast neutrons through the spallation reaction. Then the fast neutron will be moderated into short the cold,...
