Time-resolved x-ray diffraction (XRD) was used to examine the behavior of Ce under shock loading to stress states up to 22 GPa that span the shock-melt transition. Experiments reported here observed Ce held at a steady state for ∼500 ns prior to being uniaxially released to ambient pressure. Time-resolved XRD shows a constant diffraction pattern over the duration of the steady state with rapid solidification occurring on release. Cerium was found to remain crystalline as Poisson's ratio (ν) increases in the α-phase with incipient melt observed in XRD once ν reaches 0.5. Diffraction results along with sound speed measurements limit melt completion to be between 12 and 14 GPa, significantly lower than previously expected. The XRD results add confidence to previous methods used to define incipient melt and help to define a method to constrain the melt region along the Hugoniot independent of a light source.

中文翻译：

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通过铈的时间分辨 X 射线衍射研究金属的冲击熔化

时间分辨 X 射线衍射 (XRD) 用于检查 Ce 在冲击载荷下的行为，应力状态高达 22 GPa，跨越冲击熔体转变。这里报告的实验观察到 Ce 在单轴释放到环境压力之前保持在稳定状态约 500 ns。时间分辨 XRD 显示在稳定状态持续时间内的恒定衍射图案，释放时发生快速凝固。发现随着泊松比 (ν) 在 α 相中的增加，铈保持结晶，一旦 ν 达到 0.5，就在 XRD 中观察到初始熔体。衍射结果以及声速测量将熔化完成限制在 12 到 14 GPa 之间，明显低于之前的预期。