Abstract
Intense proton beam-induced heating of the spallation neutron source mercury target will cause pressure spikes that lead to the formation of cavitation bubbles in the mercury. Erosion of the mercury container walls caused by violent collapse of bubbles could potentially limit its service lifetime. In-beam tests for a limited number of pulses (<1000 pulses for each test target) have demonstrated that pitting damage appears to be especially sensitive to beam intensity, surface treatment, and gas injection. Using results of off-line pressure pulse tests conducted for a million cycles or more to scale the results from limited in-beam tests, it is concluded that the mercury target will last at least two weeks at a time-averaged proton beam power level of 1 MW. However, because of remaining uncertainties, it is concluded that further research and development and target design efforts are needed to verify these conclusions and extend the target to higher operating powers and longer lifetimes.
| Original language | English |
|---|---|
| Pages (from-to) | 58-69 |
| Number of pages | 12 |
| Journal | Journal of Nuclear Materials |
| Volume | 343 |
| Issue number | 1-3 |
| DOIs | |
| State | Published - Aug 1 2005 |
| Externally published | Yes |
| Event | Proceedings of the 6th International Workshop on Spallation Materials Technology IWSMT-6 - Duration: Nov 30 2003 → Dec 5 2003 |
Funding
The authors wish to thank the entire SNS target R&D team for their contributions to this large effort. Obtaining the more than 6000 SEM pretest and post-test images for the in-beam experiments was a formidable task that was only made possible by the efforts of a large group of SNS engineers and scientists who volunteered over a three-month period to perform this work on nights and weekends. Special thanks are also due to our collaborators at JAERI, especially Kenji Kikuchi and Masatoshi Futakawa, who developed the MIMTM device and, along with his team, conducted many tests that were critically important to our decision-making process and provided timely analysis of the pitting damage on our drop test specimens. Special thanks also go to Forschungszentrum Jülich, especially Helmut Soltner, for conducting the bubble injection target tests, and at Los Alamos National Laboratory, especially Steve Wender, Bruce Takala, Gregg Chaparro, and Valentina Tcharnotskaia, for their help in conducting the mercury target tests at WNR. This work has benefited from the use of LANSCE at the Los Alamos National Laboratory. This facility is funded by the US Department of Energy under Contract W-7405-ENG-36.
| Funders | Funder number |
|---|---|
| U.S. Department of Energy | W-7405-ENG-36 |