Thresholds for igniting exothermic reactions in Al/Ni multilayers using pulses of electrical, mechanical, and thermal energy
Thresholds for igniting exothermic reactions in Al/Ni multilayers using pulses of electrical, mechanical, and thermal energy
复制标题
DOI：
10.1063/1.4770478
复制
发表时间：
2013-01-07
影响因子：
3.2
通讯作者：
Weihs, Timothy P.
中科院分区：
文献类型：
--
作者：
Fritz, Gregory M.;Spey, Stephen J., Jr.;Weihs, Timothy P.
我们使用电能、机械能和热能脉冲来确定 Al/(Ni-7 V) 和 Al/Inconel 多层中自蔓延反应的点火阈值。对所有三种技术在具有 50 nm 双层的 Al/(Ni-7 V) 箔中引发反应所需的能量密度和功率密度进行了比较，以证明热损失对点火阈值的重要性及其对测试体积和周围热阻的依赖性。此外，当热损失非常小时，点火会在低至 232 摄氏度的温度下发生，这表明点火可以通过固态中的原子混合来控制。实验表明，点火阈值随着点火体积的增加而下降，并且随着双层间距的增加和混合厚度的增加而上升。这些趋势也得到了我们推导出的分析模型的支持，该模型用于预测点火体积、多层微观结构和物理特性对点火阈值的影响。根据测量的点火温度，我们计算出固态混合的活化能为 77.3+/-1.3 kJ/mol。 (C) 2013 年美国物理研究所。 [http://dx.doi.org/10.1063/1.4770478]
We use pulses of electrical, mechanical, and thermal energy to determine the ignition thresholds of self-propagating reactions in Al/(Ni-7 V) and Al/Inconel multilayers. The energy density and power density required to initiate reactions in a Al/(Ni-7 V) foil with a 50 nm bilayer is compared for all three techniques to demonstrate the importance of heat loss on ignition thresholds and its dependence on the test volume and the surrounding thermal resistance. In addition, ignition is shown to occur at temperatures as low as 232 degrees C when heat losses are very small suggesting that ignition can be controlled by atomic mixing in the solid state. The experiments demonstrate that the ignition threshold drops with increasing ignition volume, and it rises with increasing bilayer spacing and with increasing intermixed thickness. These trends are also supported by an analytical model we derive to predict the effects of ignition volume, multilayer microstructure, and physical properties on the ignition threshold. We calculate an activation energy of 77.3+/-1.3 kJ/mol for solid state mixing based on measured ignition temperatures. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4770478]