Evaluation of Zircaloy-4 Welding and Hydrogen Charging Effects for Use as the Structural Material for the Target Solution Vessel and Support Lines of SHINE

The subcritical hybrid intense neutron emitter (SHINE) is a proposed ⁹⁹Mo production facility to be constructed in the United States. It uses a deuterium (D) and tritium (T) fusion source to cause subcritical fission in an aqueous uranium solution, which is cycled to collect the ⁹⁹Mo products. The target solution vessel (TSV) is the container of the aqueous uranium solution, so it must remain structurally sound during operational exposure to water, fission products, neutrons, and hydrogen isotopes. The TSV will be large enough to require welding, so the exposure of joints to these same conditions must also be considered. The candidate material being investigated is Zircaloy-4. While Zircaloy-4 has a long history in the nuclear industry, it has primarily been used as fuel cladding at service temperatures of ~300°C. Zircaloy-4 must be evaluated for behavior under neutron irradiation at SHINE-relevant temperatures of