# Materials design for the synthesis of high strength radiopure copper alloys for rare event detection

## TL;DR

The paper presents a new method to design strong, radiopure copper alloys for use in advanced detectors used in rare-event physics experiments.

## Contribution

A materials design approach using computational thermodynamics is introduced to optimize radiopure copper alloys for high mechanical strength.

## Key findings

- Copper-chromium and copper-chromium-titanium alloys were identified as promising for high strength and radiopurity.
- Computational thermodynamics can predict alloy properties after thermal processing, reducing trial-and-error experimentation.
- The approach is demonstrated to benefit experiments like DarkSPHERE and XLZD.

## Abstract

Additive-free electroformed copper has emerged as the material of choice in exceptionally radiopure detectors for rare-event searches, based on its radiopurity, physical properties, and affordability. However, copper is ductile and of limited mechanical strength posing challenges for its use in future experiments. Electroformed copper-based alloys have been identified as a promising solution. However, their synthesis needs refining by exploring a complex parameter space of compositions and strengthening mechanisms. Here we show how a materials design approach may address current challenges and optimize alloy synthesis and processing. Alloy properties are predicted following thermal processing, using computational thermodynamics. The findings suggest a methodology to design high-performance, radiopure copper-based alloys suitable for next-generation rare-event experiments, while minimizing lengthy and expensive trial-and-error approaches. The impact on future experiments is exemplified through case-studies of the DarkSPHERE and XLZD experiments.

Advanced detectors for rare-event searches require materials with low radioactivity and high strength. The authors use computational thermodynamics to design electroformed copper-chromium and copper-chromium-titanium alloys with enhanced mechanical properties, while maintaining radiopurity, potentially revolutionizing materials for next-generation rare-event searches experiments like DarkSPHERE and XLZD.