Dynamic compression of cerium in the low-pressure γ-α region of the phase diagram
Dynamic compression of cerium in the low-pressure γ-α region of the phase diagram
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DOI：
10.1063/1.4732126
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发表时间：
2012-07-01
影响因子：
3.2
通讯作者：
Cherne, F. J.
中科院分区：
文献类型：
--
作者：
Jensen, B. J.;Cherne, F. J.
进行板冲击实验以检查铈对于跨越众所周知的γ-α相变的加载路径的动态响应。伽马相的异常性质和伽马-阿尔法边界处的大体积塌陷导致了斜波，随后出现了冲击载荷的冲击跳跃。这种结构波提供了一种方便的方法来定位相界并确定过渡处的体积塌陷。进行使用预热功能的实验以获得状态方程数据，定位和确定沿相界的体积压缩，并确定临界点的位置。实验结果表明，斜波峰值随着初始样品温度的增加而增加，这与转变应力的增加一致，而冲击跳跃的幅度减小。分析数据以确定沿边界的体积压缩指向 1.648 +/- 0.075 GPa 的临界点。使用冲击释放配置的附加实验用于获取释放期间的数据。所有数据与将γ相和α相视为二元合金的多相状态方程的计算结果非常一致。 (C) 2012 年美国物理研究所。 [http://dx.doi.org/10.1063/1.4732126]
Plate impact experiments were performed to examine the dynamic response of cerium for loading paths that span the well known gamma - alpha phase transition. The anomalous nature of the gamma-phase and the large volume collapse at the gamma - alpha boundary resulted in a ramp-wave followed by a shock jump for shock loading. This structured wave provided a convenient means for locating the phase boundary and determining the volume collapse at the transition. Experiments using a preheat capability were performed to obtain equation-of-state data, to locate and determine the volume compression along the phase boundary, and to determine the location of the critical point. Experimental results show that the ramp-wave peak increased with the initial sample temperature consistent with an increase in the transition stress while the magnitude of the shock jump decreased. The data were analyzed to determine the volume compression along the boundary pointing to a critical point at 1.648 +/- 0.075 GPa. Additional experiments using a shock-release configuration were used to obtain data during release. All data were in good agreement with calculations from a multiphase equation-of-state that treats the gamma and alpha phases as a binary alloy. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4732126]