NSUF 21-4307: Ion Irradiation and Examination of Additive Friction Stir Manufactured 316 Stainless Steel Component
Stainless steels are extremely relevant for current and next generation reactors. To enhance the long-term viability and competitiveness of the existing fleet and to develop an advanced reactor pipeline, it is essential to utilize advanced manufacturing technologies for nuclear applications. This proposal is focused on a relatively new solid-state technique called Additive Friction Stir Deposition (AFSD). AFSD has advantages such as higher production rate, completely dense final product, refined microstructures and mechanical property enhancement, utility as a part repair technique, and large-scale fabrication on the meter scale. The solid-state AFSD technique has potential as a modular manufacturing technology which enables a more rapid and streamlined fabrication process for large nuclear structural components. AFSD can be scaled to structures on the order of meters and has the potential to be upscaled for components as large as reactor pressure vessel shells, heads, and flanges. We want to evaluate the irradiation resistance of SS316 specimens built by AFSD. AFSD of SS316 while enabling near-net shape manufacturing of reactor components, can lead to fine-grained and ultrafine grained microstructure that can simultaneously increase the strength-ductility-toughness-irradiation resistance-corrosion resistance. For nuclear applications, it is essential to understand the microstructural evolution and the concomitant changes in mechanical properties after irradiation. The objective of this RTE proposal is to fill the gap in literature by performing studies to document the irradiation performance of AFSD 316 SS, which is extremely relevant for nuclear applications. This goal will be achieved by: (a) performing self-ion irradiations at temperatures relevant to multiple reactor concepts; (b) evaluation of mechanical properties (nanoindentation) to understand irradiation hardening mechanism; (c) microstructural characterization using TEM to examine irradiation-induced microstructural changes; (d) develop appropriate processing-structure-property-temperature-dose correlations for AFSD 316 SS; (e) understand the irradiation response of AFSD processed 316SS and compare the data with those present in the literature for 316 SS fabricated using other techniques. For this project, 3.0 MV NEC tandem accelerator at TAMU will be used for high dpa Fe self-ion irradiation. Irradiation will be performed in a high vacuum chamber along the beam line equipped with liquid nitrogen trap and multiple beam deflection setups for filtering contaminants. Samples will be irradiated by 5 MeV Fe self-ions for doses equivalent to 25, 50 and 100 dpa at 300°C (typical LWR operating temperature) and 600°C (closer to the maximum swelling temperature). The doses will be determined by using SRIM code under KP mode. The PIE tasks are, (a) perform nanoindentation of ion irradiated AFSD processed 316 SS at CAES, (b) perform TEM characterization of ion irradiated AFSD processed 316 SS at CAES, and (c) understand the effect of ion irradiation on AFSD processed 316 SS. The project performance is expected to take place during July 2021-March 2022.
Additional Info
| Field | Value |
|---|---|
| Abstract | Stainless steels are extremely relevant for current and next generation reactors. To enhance the long-term viability and competitiveness of the existing fleet and to develop an advanced reactor pipeline, it is essential to utilize advanced manufacturing technologies for nuclear applications. This proposal is focused on a relatively new solid-state technique called Additive Friction Stir Deposition (AFSD). AFSD has advantages such as higher production rate, completely dense final product, refined microstructures and mechanical property enhancement, utility as a part repair technique, and large-scale fabrication on the meter scale. The solid-state AFSD technique has potential as a modular manufacturing technology which enables a more rapid and streamlined fabrication process for large nuclear structural components. AFSD can be scaled to structures on the order of meters and has the potential to be upscaled for components as large as reactor pressure vessel shells, heads, and flanges. We want to evaluate the irradiation resistance of SS316 specimens built by AFSD. AFSD of SS316 while enabling near-net shape manufacturing of reactor components, can lead to fine-grained and ultrafine grained microstructure that can simultaneously increase the strength-ductility-toughness-irradiation resistance-corrosion resistance. For nuclear applications, it is essential to understand the microstructural evolution and the concomitant changes in mechanical properties after irradiation. The objective of this RTE proposal is to fill the gap in literature by performing studies to document the irradiation performance of AFSD 316 SS, which is extremely relevant for nuclear applications. This goal will be achieved by: (a) performing self-ion irradiations at temperatures relevant to multiple reactor concepts; (b) evaluation of mechanical properties (nanoindentation) to understand irradiation hardening mechanism; (c) microstructural characterization using TEM to examine irradiation-induced microstructural changes; (d) develop appropriate processing-structure-property-temperature-dose correlations for AFSD 316 SS; (e) understand the irradiation response of AFSD processed 316SS and compare the data with those present in the literature for 316 SS fabricated using other techniques. For this project, 3.0 MV NEC tandem accelerator at TAMU will be used for high dpa Fe self-ion irradiation. Irradiation will be performed in a high vacuum chamber along the beam line equipped with liquid nitrogen trap and multiple beam deflection setups for filtering contaminants. Samples will be irradiated by 5 MeV Fe self-ions for doses equivalent to 25, 50 and 100 dpa at 300°C (typical LWR operating temperature) and 600°C (closer to the maximum swelling temperature). The doses will be determined by using SRIM code under KP mode. The PIE tasks are, (a) perform nanoindentation of ion irradiated AFSD processed 316 SS at CAES, (b) perform TEM characterization of ion irradiated AFSD processed 316 SS at CAES, and (c) understand the effect of ion irradiation on AFSD processed 316 SS. The project performance is expected to take place during July 2021-March 2022. |
| Award Announced Date | 2021-06-07T16:16:18.613 |
| Awarded Institution | None |
| Facility | None |
| Facility Tech Lead | Lin Shao, Yaqiao Wu |
| Irradiation Facility | Accelerator Laboratory |
| PI | Rajiv Mishra |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 4307 |