SNS target tests at the LANSCE-WNR in 2001 – Part I

Evaluation of Cavitation-Erosion Resistance of 316LN Stainless Steel in Mercury Containing Metallic Solutes

“…Interpretation is hampered by a lack of very short-time exposure data, but the positive intercept implies localized erosion damage of susceptible areas occurs very quickly. This explanation is consistent with previous results indicating the [4][5][6]16 development of surface roughness and shallow pits after a very few pressure cycles.…”

Mitigation Technologies for Damage Induced by Pressure Waves in High-Power Mercury Spallation Neutron Sources (III)—Consideration of the Effect of Microbubbles on Pressure Wave Propagation through a Water Test—

“…8) As an engineering issue caused by a pressure wave, cavitation damage in liquid mercury targets raises a significant problem in the development of spallation neutron sources. [11][12][13][14][15] High-power pulsed spallation neutron sources are working in the Japan Proton Accelerator Research Complex (J-PARC) 16) and the Spallation Neutron Source (SNS) of the United States. 17) In both neutron sources, liquid mercury was selected as a target material because of its high neutron yield and high cooling performance.…”

“…The pressure waves cause a serious issue for operational stability of the neutron sources because they induce the cavitation of mercury, which results in cavitation damage on the stainless steel target vessel and degrades its structural integrity. [11][12][13][14] In order to solve this critical issue, the authors investigated a surface improvement of the target vessel walls to mitigate damage formation due to cavitation bubble collapse. 13,18) However, it was found that long-range damage mitigation by the surface improvement is very difficult and, hence, some other treatments are required.…”

Influence of Heat Treatment on Mercury Cavitation Resistance of Surface Hardened 316LN Stainless Steel

“…However, annealed 316/316LN stainless steel has been shown to be quite susceptible to pitting and erosion damage in mercury when tested under cavitation conditions produced by a split Hopkinson pressure bar apparatus [4] or a drop-test variant [5], in-beam exposures [6][7][8][9], and a vibratory horn [10][11][12][13].…”