NSUF 18-1385: Atom Probe Tomography Study of Helium precipitates in amorphous/crystalline SiOC/Fe nanocomposites

The objective of this project is to use atom probe tomography to study Helium (He) precipitate in amorphous/crystalline SiOC/Fe nanocomposites. The limited resistance of current engineering materials to radiation damage is a key factor restricting the design of next generation nuclear reactors. Introduced interfaces as point-defect sinks to remove radiation damage and suppress swelling is one of strategies to improve radiation tolerance of structural materials. For example, nanoscale metallic interfaces, e.g. interfaces of face-centered cubic and body-centered cubic alloys, have displayed strong sink strength and suppress He bubble formation. Unlike radiation responses of crystalline solids, which have been studied for decades, the fundamental processes by which amorphous alloy/crystalline composites respond to have received relatively less attention and are therefore still largely unknown. Our preliminary results show that SiOC is simultaneously resistant to ion-induced displacement damage and degradation due to implanted helium (He), markedly elevating its potential for use in advanced nuclear reactors. Several properties of SiOC can be improved, including plasticity, by introducing Fe component. We hypothesize that the SiOC/Fe interfaces in these composite systems will be strong sinks for defects in the metal component and enhance helium swelling resistance, similar or superior to what has been observed in metallic nanolayer composites. To create crystal/amorphous interfaces, magnetron sputtering will be implemented to prepare ?-Fe/SiOC multilayers and equiaxied Fe/SiOC composite. By refining the length scales of the metal and amorphous components to nanometer levels, we have achieved an abundance of crystal/amorphous interfaces in these composites, which has also been shown to dramatically improve the radiation tolerance of nanostructured crystalline composites. To test the above hypotheses, we will carry out He implantation experiment on pure SiOC and Fe/SiOC composites film and investigate He precipitate size, spatial distribution and density in both Fe and SiOC component by six days of focused ion beam with ten days of local electrode atom probe. The potential result will be the development of a new class of ceramic/metal composites that can be adapted for engineering applications, thus significantly impacting improved materials performance for advanced nuclear reactors.

추가 정보

필드	값
Abstract	The objective of this project is to use atom probe tomography to study Helium (He) precipitate in amorphous/crystalline SiOC/Fe nanocomposites. The limited resistance of current engineering materials to radiation damage is a key factor restricting the design of next generation nuclear reactors. Introduced interfaces as point-defect sinks to remove radiation damage and suppress swelling is one of strategies to improve radiation tolerance of structural materials. For example, nanoscale metallic interfaces, e.g. interfaces of face-centered cubic and body-centered cubic alloys, have displayed strong sink strength and suppress He bubble formation. Unlike radiation responses of crystalline solids, which have been studied for decades, the fundamental processes by which amorphous alloy/crystalline composites respond to have received relatively less attention and are therefore still largely unknown. Our preliminary results show that SiOC is simultaneously resistant to ion-induced displacement damage and degradation due to implanted helium (He), markedly elevating its potential for use in advanced nuclear reactors. Several properties of SiOC can be improved, including plasticity, by introducing Fe component. We hypothesize that the SiOC/Fe interfaces in these composite systems will be strong sinks for defects in the metal component and enhance helium swelling resistance, similar or superior to what has been observed in metallic nanolayer composites. To create crystal/amorphous interfaces, magnetron sputtering will be implemented to prepare ?-Fe/SiOC multilayers and equiaxied Fe/SiOC composite. By refining the length scales of the metal and amorphous components to nanometer levels, we have achieved an abundance of crystal/amorphous interfaces in these composites, which has also been shown to dramatically improve the radiation tolerance of nanostructured crystalline composites. To test the above hypotheses, we will carry out He implantation experiment on pure SiOC and Fe/SiOC composites film and investigate He precipitate size, spatial distribution and density in both Fe and SiOC component by six days of focused ion beam with ten days of local electrode atom probe. The potential result will be the development of a new class of ceramic/metal composites that can be adapted for engineering applications, thus significantly impacting improved materials performance for advanced nuclear reactors.
Award Announced Date	2018-05-17T10:56:20.317
Awarded Institution	None
Facility	None
Facility Tech Lead	Yaqiao Wu
Irradiation Facility	None
PI	Qing Su
PI Email	[email protected]
Project Type	RTE
RTE Number	1385