Dissertation
Grain boundary influence on radiation induced defect evolution in nanocrystalline metals
Doctor of Philosophy (Ph.D.), Drexel University
Aug 2019
DOI:
https://doi.org/10.17918/00000090
Abstract
The development of materials that can better withstand the operating environment within nuclear reactors is of critical importance for the longevity of existing and the robustness of future nuclear energy systems. It is conjectured that nanocrystalline materials should exhibit significant reductions in radiation damage, however despite extensive studies, fundamental questions remain regarding defect evolution and migration to grain boundaries. Specifically, the role of grain size and grain boundary properties must be understood to develop insights into how to create new material microstructures that have enhanced radiation tolerance. The work presented makes use of in situ and ex situ experimental approaches to examine the role of grain size and grain boundary character in response to radiation damage in model FCC metals. Heavy ion irradiation experiments were carried out on metal foils under varying experimental conditions followed by post-irradiation analysis of grains ranging from 10 nm to 200 nm in size. Transmission electron microscopy (TEM) and related techniques were used to evaluate defect densities (dislocations and cavities) and defect cluster size as a function of grain size and grain boundary misorientation. Phenomena related to grain boundary response to damage absorption and sink efficiency are examined as well. The goal of this work is to contribute to building a fundamental framework for microstructural design to fabricate more radiation tolerant materials.
Metrics
58 File views/ downloads
11 Record Views
Details
- Title
- Grain boundary influence on radiation induced defect evolution in nanocrystalline metals
- Creators
- James E. Nathaniel II
- Contributors
- Mitra Taheri (Advisor)
- Awarding Institution
- Drexel University
- Degree Awarded
- Doctor of Philosophy (Ph.D.)
- Publisher
- Drexel University; Philadelphia, Pennsylvania
- Number of pages
- xvii, 175 pages
- Resource Type
- Dissertation
- Language
- English
- Academic Unit
- Materials (Science and) Engineering (Metallurgical Engineering) (1970-2026); College of Engineering (1970-2026); Drexel University
- Other Identifier
- 991014695242704721