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arXiv · 1201.0427

Sound velocity measurements of tantalum under shock compression in the 10-110 GPa range

Jianbo Hu·Chengda Dai·Yuying Yu·Zijiang Liu·Ye Tan·Xianming Zhou·Hua Tan·Lingcang Cai·Qiang wu
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Abstract

The high-pressure melting curve of tantalum (Ta) has been the center of a long-standing controversy. Sound velocities along the Hugoniot curve are expected to help in understanding this issue. To that end, we employed a direct-reverse impact technique and velocity interferometry to determine sound velocities of Ta under shock compression in the 10-110 GPa pressure range. The measured longitudinal sound velocities show an obvious kink at ~60 GPa as a function of shock pressure, while the bulk sound velocities show no discontinuity. Such observation could result from a structural transformation associated with a negligible volume change or an electronic topological transition.

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Jianbo Hu, Chengda Dai, Yuying Yu, Zijiang Liu, Ye Tan, Xianming Zhou, Hua Tan, Lingcang Cai, Qiang wu. 2012-02-16. Sound velocity measurements of tantalum under shock compression in the 10-110 GPa range. https://doi.org/10.1063/1.3681815

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