Observation of microstructure for high Z material under extreme conditions using dynamic X-ray diffraction
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更新:2024-04-26 00:23:35 浏览:186次
张贴报告
摘要
The dynamic response characteristics of matter under extreme conditions largely depend on the microstructure of materials, and have significant importance in many fields such as aerospace, national defense, and basic science. The dynamic X-ray diffraction (DXRD) is an in-situ real time diagnostic technique, which allows for direct observation of transient microstructure under dynamic loading. A series of laser-driven dynamic compression experiments have been carried out to investigate the exotic and complex behavior predicted by first-principles theory via dynamic X-ray diffraction, like the polymorphism of various materials under high pressure and temperature. High Z materials generally have high density and strong X-ray absorption, which makes the DXRD much more difficult, thus X-ray sources with higher photon energy are needed.
Here, germanium and zirconium were driven by high power laser in different ways, generating quasi-monochromatic He-α X-ray and the spectrum were obtained by bent crystal spectrometer. Also, the high energy X-ray sources were used to probe the laser-driven tantalum samples, which is a typical high Z material. We successfully obtained the diffraction patterns from shock compressed tantalum samples via DXRD. The development of DXRD technique for high Z materials means that we can further expand the research scope of dynamic response characteristics of materials under extreme conditions, and it is expected to play an important role in the research of high-pressure state equations and physical properties, as well as engineering application.
关键词
Dynamic X-ray diffraction,X-ray source
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