Publication Date
8-2017
Date of Final Oral Examination (Defense)
5-17-2017
Type of Culminating Activity
Dissertation
Degree Title
Doctor of Philosophy in Materials Science and Engineering
Department
Materials Science and Engineering
Major Advisor
Janelle P. Wharry, Ph.D.
Major Advisor
Hui Xiong, Ph.D.
Advisor
Yaqiao Wu, Ph.D.
Advisor
James Cole, Ph.D.
Abstract
The objective of this study is to evaluate the mechanism of irradiation-induced nanoparticle evolution in a model Fe-9%Cr oxide dispersion strengthened steel and commercial ferritic-martensitic alloys HCM12A and HT9. Each alloy is irradiated with Fe2+ ions, protons, or neutrons to doses ranging from 1-100 displacements per atoms at 500°C. The morphology of nanoclusters are characterized using atom probe tomography. The evolution of clusters in each alloy are notably different with each irradiating particle, and the competing effects of ballistic dissolution and radiation-enhanced, diffusion-driven growth are attributed to the respective differences in cluster evolution. A phase evolution model, originally theorized by Nelson, Hudson, and Mazey, is used to simulate time-dependent nanocluster irradiation evolution in each alloy, with useful insights achieved to inform future alloy development. In all cases, a downward temperature shift is required to emulate low-dose-rate nanocluster evolution using higher-dose-rate irradiations.
DOI
https://doi.org/10.18122/B2GX21
Recommended Citation
Swenson, Matthew John, "The Mechanism of Radiation-Induced Nanocluster Evolution in Oxide Dispersion Strengthened and Ferritic-Martensitic Alloys" (2017). Boise State University Theses and Dissertations. 1319.
https://doi.org/10.18122/B2GX21
Included in
Metallurgy Commons, Other Materials Science and Engineering Commons, Structural Materials Commons