Current investigations into neutrinoless double beta decay and the direct detection of dark matter require increasingly sensitive detector systems that demand ultra-low background materials. These requirements have previously been attained using ultra-radiopure electroformed (EF) copper. However, pure copper possesses high ductility and relatively low strength, which necessitates the need for large amounts of material and extra care during fabrication to help minimize galling and mechanical failure. We investigate an alloying alternative to pure EF copper by examining low wt% copper chrome (Cu–Cr) solid solution alloys, with inquiries into alloy hardness, strength, and radiopurity. Alloyed Cu–Cr layered samples are shown to exhibit significantly increased hardness compared to EF copper, for example showing a 50% increase in exhibited hardness using less than 1% Cr by weight, with limited negative impact to the material’s radiopurity.
Published: August 26, 2025
Citation
Vitale A.J., I.J. Arnquist, K. Harouaka, B.J. Garcia, N.R. Overman, T.J. Roosendaal, and E.W. Hoppe. 2021.A Preliminary Investigation into the Electrodeposition and Synthesis of Radiopure Copper-Chromium Alloys for Rare-Event Physics Detector System.Nuclear Instruments and Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1003:165291.PNNL-SA-155529.doi:10.1016/j.nima.2021.165291