NSUF 16-846: The window of gas-bubble superlattice formation in bcc metals
Gas-bubble superlattice (GBS) have been observed for decades, they can form either by gas ion implantation or by nuclear transmutation. Although many possible GBS formation mechanisms have been proposed previously, a clear understanding is still missing. Gas bubble superlattice typically form adopts the same structure as the matrix crystal structure, while Gan et al. (Journal of Nuclear Materials, 396 (2010): 234-239. ) recently reported that Xenon bubbles form a fcc superlattice in a bcc uranium-molybdenum alloy under neutron irradiation. In general, the gas-bubble diameter is about 2 nm, uniformly distributed in the matrix, however, Johnson et al. (Nature, 347(1990): 265-267.) reported that a “macrolattice” with a bubble diameter of about 60 nm coexisted with the small-bubble lattice in helium-implanted gold. Understanding the fundamental mechanism of GBS formation in irradiated materials is crucial for the development of advanced nuclear materials with desired properties in a controllable way. Here we hypothesize that the driving mechanism behind GBS formation is anisotropy, either in elasticity or via self-interstitial atom diffusion. To test this hypothesis, a few materials of unique isotropic/anisotropic properties will be investigated, using closely correlated ion implantation experiments and simulations. In this proposal, two pure metals, molybdenum (Mo) and tungsten (W), will be implanted with noble gas ions. Tungsten is elastically isotropic, while its self-interstitial atom (SIA) diffusion is anisotropic, molybdenum is elastically anisotropic and its SIA diffusion is also anisotropic.
Additional Info
| Field | Value |
|---|---|
| Awarded Institution | Idaho National Laboratory |
| Embargo End Date | 2026-02-27 |
| Facility Tech Lead | Kevin Field |
| NSUF Call | FY 2017 RTE 1st Call |
| PI | Cheng Sun |
| Project Member | Dr. Jian Gan, Research Scientist - Idaho National Laboratory (https://orcid.org/0000-0002-9121-4164) |
| Project Member | Dr. Lingfeng He, Associate Professor - North Carolina State University (https://orcid.org/0000-0003-2763-1462) |
| Project Member | Dr. Cheng Sun, Associate Professor - Clemson University (https://orcid.org/0000-0003-4104-8898) |
| Project Notes | Awarded on 12/16/2016 |
| Project Type | RTE |
| Publication | Formation of tetragonal gas bubble superlattice in bulk molybdenum under helium ion implantation Cheng Sun, David Sprouster, Khalid Hattar, Lynne Ecker, Lingfeng He, Yipeng Gao, Yongfeng Zhang, Jian Gan Scripta Materialia 149 2018-05-01 https://www.sciencedirect.com/science/article/pii/S135964621830040X#ac0005 |
| Publication | Thermal stability of helium bubble superlattice in Mo under TEM in-situ heating Jian Gan, Cheng Sun, Lingfeng He, Yongfeng Zhang, Yipeng Gao Journal of Nuclear Materials 505 2018-07-02 https://www.sciencedirect.com/science/article/pii/S0022311518301065#ack0010 |
| Publication | Theoretical Predictions, Atomistic Simulations and Experimental Observations of Void and Gas Bubble Superlattice Formation under Irradiation David Sprouster TMS 2019 2019-03-10 - 2019-03-14 |
| Publication | Irradiation-Dependent Helium Gas Bubble Superlattice in Tungsten David Sprouster Scientific Reports 9 2019-02-19 https://www.nature.com/articles/s41598-019-39053-0 |
| Publication | Analysis Techniques for Large Data sets from the National Synchrotron Light Source-II David Sprouster Transactions of the American Nuclear Society 118 2018-06-17 http://ansannual.org/wp-content/2018/Data/pdfs/641-25055.pdf |
| Publication | Disordering of helium gas bubble superlattices in molybdenum under ion irradiation and thermal annealing David Sprouster Journal of Nuclear Materials 539 2020-06-08 https://doi.org/10.1016/j.jnucmat.2020.152315 |
| Publication | Formation window of gas bubble superlattice in molybdenum under ion implantation David Sprouster Physical Review Materials 3 2019-10-31 https://doi.org/10.1103/PhysRevMaterials.3.103607 |
| Publication | Self-Organization of Gas Bubble Superlattices David Sprouster TMS 2018 2018-03-11 - 2018-03-16 |
| RTE Number | 846 |