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Title: Measuring Effects of Radiation on Precipitates in Aluminum 7075-T6 Using Differential Scanning Calorimetry
Radiation damage in structural materials for nuclear applications is not well-understood, especially when linking the atomic scale damage mechanisms to the macroscopic effects. On a microscopic level, particle radiation creates defects that can accumulate in the material. Defects can also interact with existing features in the material. Since both defects and features have different energies associated with them, investigation of the resulting energy spectrum in a macroscopic sample may offer insight into the connection between microscopic damage and macroscopic properties. In alloys, changes in the size and number of precipitates will be reflected in the amount of energy required to dissolve the precipitates during thermal analysis. This can then be studied using differential scanning calorimetry (DSC). This work explores the sensitivity of the DSC measurement to detect irradiation-induced instability in metastable and secondary phase precipitates in the high-strength aluminum alloy 7075-T6 for extremely low doses of helium-ion and neutron irradiation. The precipitates in aluminum 7075-T6 are expected to grow or shrink, changing the energy spectrum measured by DSC. The magnitude of the change can then be compared to a model of irradiation-induced phase instability. This will demonstrate the ability of this thermal analysis technique to help bridge the gap between microscopic radiation effects and macroscopic properties.  more » « less
Award ID(s):
1654548
PAR ID:
10499084
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
American Society of Mechanical Engineers
Date Published:
Journal Name:
Proceedings of the 2018 26th International Conference on Nuclear Engineering ICONE26
ISBN:
978-0-7918-5153-1
Subject(s) / Keyword(s):
Irradiation polymers stored energy uranium enrichment
Format(s):
Medium: X
Location:
London, England
Sponsoring Org:
National Science Foundation
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