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DOE OSTI · 2588928

Recrystallization, cracking, and erosion of dispersoid-strengthened tungsten materials during exposure to divertor plasmas

Kolasinski, Robert D. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)] (ORCID:0000000296331845)·Coburn, Jonathan D. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)] (ORCID:0000000156180483)·Truong, Dihn D. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)]·Watkins, Jonathan George [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)]·Abrams, Tyler [General Atomics, San Diego, CA (United States)] (ORCID:0000000296056871)·Fang, Z. Zak [Univ. of Utah, Salt Lake City, UT (United States)]·Hood, Ryan Thomas [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)] (ORCID:0000000337893116)·Nygren, Richard E. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)]·Leonard, Anthony W. [General Atomics, San Diego, CA (United States)]·Ren, Jun [Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0000000222561007)·Rudakov, Dmitry L. [Univ. of California, San Diego, CA (United States)]·Sugar, Joshua Daniel [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)] (ORCID:0009000245752807)·Tsui, Cedric Kar Wai [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)]·Wang, Huiqian Q. [General Atomics, San Diego, CA (United States)]·Whaley, Josh A. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)]·Bykov, Igor [General Atomics, San Diego, CA (United States)] (ORCID:0000000165196081)·Cruz, Antonio Jose [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)] (ORCID:000900013646868X)·Glass, Fenton [General Atomics, San Diego, CA (United States)] (ORCID:0000000311011859)·Herfindal, Jeffrey [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:000000032846597X)·Lasnier, Charlie [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]·Marini, Claudio [Univ. of California, San Diego, CA (United States)] (ORCID:0000000348197765)·McLean, Adam [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]·Moser, Auna L. [General Atomics, San Diego, CA (United States)]·Nishimoto, Ryan Kirk [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)]·Wilcox, Robert [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000313691739)·York, Warren Lee [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)]
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Abstract

In this study, we investigated the effects of combined intense particle and heat flux exposure on advanced tungsten plasma-facing materials within the DIII-D fusion facility. Our test matrix included two types of dispersoid-strengthened tungsten (containing either 100 nm diameter TiO 2 or Ni particles), along with high-purity polycrystalline tungsten as a reference. This experiment relied on a sample geometry angled at 15° relative to the divertor surface, thereby allowing the surfaces to intercept steady-state perpendicular heat fluxes (q ⟂ ) ranging from 10.1 to 19.6 MW/m 2 . During each shot, the samples were exposed to 42 Hz edge-localized modes (ELMs), allowing us to test the material response to transient heating. We correlated the exposure conditions with extensive post-test surface composition analysis and microscopy to determine how the plasma modified each surface. The angled specimens closest to the strike point received the highest combined heat and particle flux and melted midway through the experiment. EBSD analysis revealed they were completely recrystallized throughout, with an average grain size >100 µm. On the other hand, the specimens that received a lower steady state heat flux survived with more superficial surface damage. Whereas the high-purity polycrystalline tungsten exhibited a higher surface roughness, the dispersoid-strengthened material exhibited more extensive shallow inter-granular cracking. In addition, the surface was depleted of dispersoids following plasma exposure, possibly because of evaporation and/or sputtering. The results described here provide insights into the performance of these materials in a fusion environment which can guide further optimization for use in long-pulse devices.

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BibTeXRIS

Kolasinski, Robert D. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)] (ORCID:0000000296331845), Coburn, Jonathan D. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)] (ORCID:0000000156180483), Truong, Dihn D. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)], Watkins, Jonathan George [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)], Abrams, Tyler [General Atomics, San Diego, CA (United States)] (ORCID:0000000296056871), Fang, Z. Zak [Univ. of Utah, Salt Lake City, UT (United States)], Hood, Ryan Thomas [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)] (ORCID:0000000337893116), Nygren, Richard E. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)], Leonard, Anthony W. [General Atomics, San Diego, CA (United States)], Ren, Jun [Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0000000222561007), Rudakov, Dmitry L. [Univ. of California, San Diego, CA (United States)], Sugar, Joshua Daniel [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)] (ORCID:0009000245752807), Tsui, Cedric Kar Wai [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)], Wang, Huiqian Q. [General Atomics, San Diego, CA (United States)], Whaley, Josh A. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)], Bykov, Igor [General Atomics, San Diego, CA (United States)] (ORCID:0000000165196081), Cruz, Antonio Jose [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)] (ORCID:000900013646868X), Glass, Fenton [General Atomics, San Diego, CA (United States)] (ORCID:0000000311011859), Herfindal, Jeffrey [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:000000032846597X), Lasnier, Charlie [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Marini, Claudio [Univ. of California, San Diego, CA (United States)] (ORCID:0000000348197765), McLean, Adam [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Moser, Auna L. [General Atomics, San Diego, CA (United States)], Nishimoto, Ryan Kirk [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)], Wilcox, Robert [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000313691739), York, Warren Lee [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)]. 2025-09-05. Recrystallization, cracking, and erosion of dispersoid-strengthened tungsten materials during exposure to divertor plasmas. https://doi.org/10.1016/j.nme.2025.101982

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