Elasticity and rheology of platinum under high pressure and nonhydrostatic stress
Elasticity and rheology of platinum under high pressure and nonhydrostatic stress
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高压和非静水应力下铂的弹性和流变学
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
T. Duffy
中科院分区：
文献类型：
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作者：
A. Kavner;T. Duffy
利用金刚石压砧非流体静力压缩条件下的径向X射线衍射，我们确定了室温下多晶铂在4.2~22.4GPa压力范围内的屈服强度下限为2.2~3.3GPa。还计算了铂的弹性各向异性S = 2（S11-S12）/S44，在整个压力范围内等于1.47（16）。此外，在环境温度下以及在一组单独的实验中，在激光加热期间，铂在非静水应力下均表现出与时间相关的弛豫。铂在300 K和1200 K时的平均应变速率分别为10 - 7s-1和10 - 5s-1，导致铂在300 K和1200（300）K时的有效蠕变粘度分别为10 - 15Pas和10 - 13Pas。
Using radial x-ray diffraction under nonhydrostatic compression in a diamond-anvil cell, we determine a lower bound of the yield strength of polycrystalline platinum to be 2.2 to 3.3 GPa in the pressure range of 4.2 to 22.4 GPa at room temperature. The elastic anisotropy S = 2(S 1 1 -S 1 2 )/S 4 4 of platinum is also evaluated, and is equal to 1.47(16) throughout this pressure range. In addition, platinum shows a time-dependent relaxation under nonhydrostatic stress at both ambient temperatures and, in a separate set of experiments, during laser heating. Average strain rates measured for platinum are 10 - 7 s - 1 at 300 K and 10 - 5 s - 1 at 1200 K, resulting in effective creep viscosities of 10 1 5 Pas at 300 K and 10 1 3 Pas at 1200(300) K.