The microstructures of materials typically undergo significant changes during shock loading, causing failure when higher shock pressures are reached. However, preservation of microstructural and mechanical integrity during shock loading are essential in situations such as space travel, nuclear energy, protection systems, extreme geological events, and transportation. Here, we report ex situ shock behavior of a chemically optimized and microstructurally stable, bulk nanocrystalline copper–tantalum alloy that shows a relatively unchanged microstructure or properties when shock compressed up to 15 GPa. The absence of shock-hardening indicates that the grains and grain boundaries that make up the stabilized nanocrystalline microstructure act as stable sinks, thereby annihilating deformation-induced defects during shock loading. This study helps to advance the possibility of developing advanced structural materials for extreme applications where shock loading occurs.
Energy absorption by matter is fundamental to natural and man-made processes. However, despite this ubiquity, developing materials capable of withstanding severe energy fluxes without degradation is a significant challenge in materials science and engineering. Despite recent advances in creating alloys resistant to energy fluxes, mitigating the damage caused by the absorption and transfer of mechanical energy remains a critical obstacle in both fundamental science and technological applications. This challenge is especially prominent when the mechanical energy is transferred to the material by shock loading. This study demonstrates a phenomenon in which microstructurally stabilized nanocrystalline Cu-Ta alloys can undergo reversal or nearly complete recovery of the dislocation structure after multiple shock-loading impacts, unlike any other known metallic material. The microstructure of these alloys can withstand repeated shock-wave interactions at pressures up to 12 GPa without any significant microstructural damage or deterioration, demonstrating an extraordinary capacity to be virtually immune to the detrimental effects of shock loading.
more » « less- PAR ID:
- 10550391
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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