Rapid Primary Radiation Damage Resistance Assessment of Precipitation-Hardened Cu Alloys

TL;DR

This paper introduces a rapid, in situ method using transient grating spectroscopy to predict radiation damage resistance in Cu alloys, significantly speeding up material screening for radiation environments.

Contribution

It establishes a direct correlation between TGS measurements and microstructural damage, enabling quick assessment of radiation resistance in Cu alloys.

Findings

SAW frequency decrease correlates with void density

In situ TGS predicts damage within minutes

Method tested on three Cu-Cr-Ta compositions

Abstract

This study establishes a direct correlation between in situ irradiation-induced property changes measured by transient grating spectroscopy (TGS) and the resulting microstructural damage in Cu-Cr-Ta alloys. Thin films fabricated by physical vapor deposition were irradiated with 6.6 MeV Cu +3 ions up to 25 DPA, while TGS continuously monitored the evolution of surface acoustic wave (SAW) frequency and thermal diffusivity. Post-irradiation transmission electron microscopy (TEM) was used to quantify void formation as a metric of accumulated radiation damage. A pronounced decrease in SAW frequency was observed some seconds after the onset of irradiation, and it was found to correlate strongly with the final void density. Vacancy MEB calculations propose that the small decrease in SAW frequency is associated with the low population of mobile vacancies, promoting defect recombination and decreasing void formation. This relationship enables early prediction of relative radiation damage resistance within minutes of irradiation, substantially reducing the time required compared to conventional irradiation and postcharacterization routes, allowing rapid screening of multiple compositions. We were able to test this method with 3 compositions of the Cu-Cr-Ta system. More generally, this in situ approach provides an efficient pathway for accelerating the development of materials for radiation environments.