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Colin Judge: Testing structural materials in Idaho’s newest hot cell facility
Idaho National Laboratory’s newest facility—the Sample Preparation Laboratory (SPL)—sits across the road from the Hot Fuel Examination Facility (HFEF), which started operating in 1975. SPL will host the first new hot cells at INL’s Materials and Fuels Complex (MFC) in 50 years, giving INL researchers and partners new flexibility to test the structural properties of irradiated materials fresh from the Advanced Test Reactor (ATR) or from a partner’s facility.
Materials meant to withstand extreme conditions in fission or fusion power plants must be tested under similar conditions and pushed past their breaking points so performance and limitations can be understood and improved. Once irradiated, materials samples can be cut down to size in SPL and packaged for testing in other facilities at INL or other national laboratories, commercial labs, or universities. But they can also be subjected to extreme thermal or corrosive conditions and mechanical testing right in SPL, explains Colin Judge, who, as INL’s division director for nuclear materials performance, oversees SPL and other facilities at the MFC.
SPL won’t go “hot” until January 2026, but Judge spoke with NN staff writer Susan Gallier about its capabilities as his team was moving instruments into the new facility.
M. Z. Youssef, Y. Watanabe
Fusion Science and Technology | Volume 19 | Number 3 | May 1991 | Pages 1967-1973
Neutronic | Proceedings of the Ninth Topical Meeting on the Technology of Fusion Energy (Oak Brook, Illinois, October 7-11, 1990) | doi.org/10.13182/FST91-A29630
Articles are hosted by Taylor and Francis Online.
The accuracy of beryllium data, particularly the 9Be(n,2n) cross-section and the associated secondary neutrons energy distribution has direct impact on the prediction accuracy of important neutronics parameters such as in-blanket neutron spectra, tritium production and other reaction rates distributions. The measured values for these parameters obtained within the U.S./JAERI Collaborative Program on Fusion Integral Experiments were compared to the calculated ones with three evaluations for beryllium data. The ENDF/B-V, LANL, and ENDF/B-VI evaluations for beryllium (denoted Be5, (LANL)Be, and Be6, respectively) were processed, along with ENDF/B-V data of other materials, into 80-group neutron structure of the MATSX6 library. The processed library was used to calculate tritium production rate, neutron spectrum, and several foil activation reaction rates along the central axis of a Li2O test assembly in which a 5 cm-thick beryllium zone precedes the Li2O zone and acts as a neutron multiplier. The test assembly itself is located at one end of a Li2CO3 enclosure where the D-T neutron point source is located inside the inner cavity. Examination of the Be data indicates that the total Be(n,2n) cross-section of B6 is lower than that of B5 and (LANL)Be by ∼ 10–15% at high incident energies and that this cross-section is very similar in the case of B5 and (LANL)Be evaluation. However, the secondary energy distribution (SED) from this reaction is noticeably different among the three evaluations; the SED in Be6 evaluation does not extend down below ∼ IKeV while the (LANL)Be evaluation extends down below ∼ 1 KeV, but the cross-section in this energy range is negligible. On the other hand, in the Be5 evaluation, the SED extends down to very low energies. The impact of these differences on tritium production from 6Li(T6) and 7Li(T7) is that the calculated-to-measured values (C/E) for T6 have improved with the Be6 by ∼ 3–5% (C/E = 1.05) as compared to those obtained by the Be5 and (LANL)Be evaluations in the bulk of the Li2O zone. The C/E values for the high threshold reactions [e.g., 58Ni(n,2n)] have also improved by 3–7%. By comparing the calculated spectra to the measured ones at various locations, it was noticed that the 14 MeV peak is better predicted by the Be6 evaluation.
