NSUF 17-971: The in-situ observation of radiation resistance mechanism in metal-1D/2D nanocomposites for structural material and fuel cladding of next generation reactors
The objective of this project is to reveal the underlying mechanism of the role of 1D/2D nanofiller in nanocomposite to improve the radiation resistance. We have achieved the dispersion of 1D carbon nanotubes (CNTs) inside grains which efficiently resist lattice dislocations for both low-temperature glide and high-temperature climb, and resist the diffusion of vacancies and interstitials, without sacrificing tensile ductility.1 From the in-situ TEM experiment, we found that the CNT was embedded into Al grain through cold welding2. Ion irradiation of the nanocomposites demonstrated improved irradiation resistance. The CNTs survived under low energy helium ion irradiation up to 72 DPA via restructuring. High energy Al self-ion irradiation converts CNT to Al4C3, but still as slender 1D nanorods that continue to catalyze recombination of radiation defects. This special finding of the self-healing of 1D filler makes the metal-CNT composites could be one of the ideal candidates for the nuclear materials up to 102 DPA. However, in spite of the significant improvement, the development of the next-generation nuclear reactors sets an extremely high standard, where the radiation tolerance requirement could be as high as ~103 DPA. To achieve this goal, we dispersed 2D structure into metal such as Al and Cu, further increasing interfacial area (defect sinks). Compared to “1D nanoengineered” CNTs/metal composite, “2D nanoengineered” network of GBs3 has four times shorter Lfurthest and 15 times more interfacial area. Therefore, dispersion of the 2D materials (such as graphene) in metal is promising to obtain a radiation tolerance at least one order of magnitude higher than 1D CNTs/metal composites. In order to understand the major role of the interface in 2D or mixture of 1D/2D nanodispersion as nuclear materials, and the underlying mechanism of their radiation resistance, we plan to investigate the basic radiation material science, in particular, metals (Cu/Al)-graphene using a high-energy ion accelerator. The local structural evolution at the interface will provide a critical quantitative/qualitative information from the recombination of interstitials and vacancies and outgassing through its percolating network. We propose to use the IVEM-Tandem to observe the evolution of microstructure especially phase transformation during ion bombardment. This study will provide insights on the role of 1D/2D filler to improve the radiation resistance, enabling better understanding of the irradiation mechanism at the nanoscale. Even though interior dispersion of 1D/2D carbon in metal without losing the integrity of the nanodispersoids is the key technology to enhance the properties, So far, very limited research had been performed on the dispersion of 1D/2D carbon inside the metal grains. Once the underlying mechanism is successfully revealed, the potential impact to our state-of-the-knowledge is the designing of the type, shape, and size of the intragranular 1D/2D filler to enhance the radiation resistance. The fabrication from the nanoscale cold welding provides more freedom to choose the matrix and fillers independent of chemical composition and physical properties as one can easily overcome a barrier of thermodynamic stability. The timeframe for the execution of the project: The samples are ready. We can take any time from Apr.13, 2017 to Dec. 13, 2017
Additional Info
| Field | Value |
|---|---|
| Abstract | The objective of this project is to reveal the underlying mechanism of the role of 1D/2D nanofiller in nanocomposite to improve the radiation resistance. We have achieved the dispersion of 1D carbon nanotubes (CNTs) inside grains which efficiently resist lattice dislocations for both low-temperature glide and high-temperature climb, and resist the diffusion of vacancies and interstitials, without sacrificing tensile ductility.1 From the in-situ TEM experiment, we found that the CNT was embedded into Al grain through cold welding2. Ion irradiation of the nanocomposites demonstrated improved irradiation resistance. The CNTs survived under low energy helium ion irradiation up to 72 DPA via restructuring. High energy Al self-ion irradiation converts CNT to Al4C3, but still as slender 1D nanorods that continue to catalyze recombination of radiation defects. This special finding of the self-healing of 1D filler makes the metal-CNT composites could be one of the ideal candidates for the nuclear materials up to 102 DPA. However, in spite of the significant improvement, the development of the next-generation nuclear reactors sets an extremely high standard, where the radiation tolerance requirement could be as high as ~103 DPA. To achieve this goal, we dispersed 2D structure into metal such as Al and Cu, further increasing interfacial area (defect sinks). Compared to “1D nanoengineered” CNTs/metal composite, “2D nanoengineered” network of GBs3 has four times shorter Lfurthest and 15 times more interfacial area. Therefore, dispersion of the 2D materials (such as graphene) in metal is promising to obtain a radiation tolerance at least one order of magnitude higher than 1D CNTs/metal composites. In order to understand the major role of the interface in 2D or mixture of 1D/2D nanodispersion as nuclear materials, and the underlying mechanism of their radiation resistance, we plan to investigate the basic radiation material science, in particular, metals (Cu/Al)-graphene using a high-energy ion accelerator. The local structural evolution at the interface will provide a critical quantitative/qualitative information from the recombination of interstitials and vacancies and outgassing through its percolating network. We propose to use the IVEM-Tandem to observe the evolution of microstructure especially phase transformation during ion bombardment. This study will provide insights on the role of 1D/2D filler to improve the radiation resistance, enabling better understanding of the irradiation mechanism at the nanoscale. Even though interior dispersion of 1D/2D carbon in metal without losing the integrity of the nanodispersoids is the key technology to enhance the properties, So far, very limited research had been performed on the dispersion of 1D/2D carbon inside the metal grains. Once the underlying mechanism is successfully revealed, the potential impact to our state-of-the-knowledge is the designing of the type, shape, and size of the intragranular 1D/2D filler to enhance the radiation resistance. The fabrication from the nanoscale cold welding provides more freedom to choose the matrix and fillers independent of chemical composition and physical properties as one can easily overcome a barrier of thermodynamic stability. The timeframe for the execution of the project: The samples are ready. We can take any time from Apr.13, 2017 to Dec. 13, 2017 |
| Award Announced Date | 2017-04-26T10:14:19.71 |
| Awarded Institution | Center for Advanced Energy Studies |
| Facility | Microscopy and Characterization Suite |
| Facility Tech Lead | Alina Zackrone, Wei-Ying Chen, Yaqiao Wu |
| Irradiation Facility | None |
| PI | Ju Li |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 971 |