Abstract
Silicon carbide (SiC) for nuclear structural applications, whether in the monolithic ceramic or composite form, will require a robust joining technology capable of withstanding the harsh nuclear environment. This paper presents significant progress made towards identifying and processing irradiation-tolerant joining methods for nuclear-grade SiC. In doing so, a standardized methodology for carrying out joint testing has been established consistent with the small volume samples mandated by neutron irradiation testing. Candidate joining technologies were limited to those that provide low induced radioactivity and included titanium diffusion bonding, Ti-Si-C MAX-phase joining, calcia-alumina glass-ceramic joining, and transient eutectic-phase SiC joining. Samples of these joints were irradiated in the Oak Ridge National Laboratory High Flux Isotope Reactor at 500 or 800 °C, and their microstructure and mechanical properties were compared to pre-irradiation conditions. Within the limitations of statistics, all joining methodologies presented retained their joint mechanical strength to ∼3 dpa at 500 °C, thus indicating the first results obtained on irradiation-stable SiC joints. Under the more aggressive irradiation conditions (800 °C, ∼5 dpa), some joint materials exhibited significant irradiation-induced microstructural evolution; however, the effect of irradiation on joint strength appeared rather limited.
Original language | English |
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Pages (from-to) | 497-511 |
Number of pages | 15 |
Journal | Journal of Nuclear Materials |
Volume | 448 |
Issue number | 1-3 |
DOIs | |
State | Published - May 2014 |
Funding
This work was supported by Office of Fusion Energy Sciences, US Department of Energy under contract DE-AC05-00OR22725 with UT-Battelle, LLC, and US-Japan TITAN Collaboration on Fusion Blanket Technology and Materials. Research supported in part by ORNL’s Shared Research Equipment (ShaRE) User Facility and High Flux Isotope Reactor, which are sponsored by the Office of Basic Energy Sciences, U.S. Department of Energy. The authors are thankful to K.A. Terrani for providing a technical review of the manuscript and useful discussion, K. Toyoshima for microscopy, R.A. Meisner for XRD analysis, and S.M. Curlin, P.S. Tedder, and A.M. Williams for support in post-irradiation examination. This manuscript has been authored by the Oak Ridge National Laboratory, managed by UT-Battelle LLC under Contract No. DE-AC05-00OR22725 with the US Department of Energy. The US Government retains and the publisher, by accepting the article for publication, acknowledges that the US Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US Government purposes.