Experimental investigations have been carried out to establish a correlation of energy coupling efficiency in fast electrical explosion of different metals with known electrical and thermophysical properties. To cover a wide range of metal properties, in the present study, five metals (Au, Cu, Al, W, and Ti) are considered from two well-known groups (refractory and non refractory) and palladium is included as sixth metal having intermediate properties between these two. Comparative study is carried out for the same circuit parameters (current rate $\approx 90 \times 10^{9}$ A/s) to explore electrically exploding wire (EEW) behavior of these metals in two different media: air and vacuum. Temporal evolution of self-emitted light around these metal wires is analyzed as a qualitative measure for energy diversion from the metal core to outer corona and is recorded using streak camera for both media. In air, refractory and non refractory metals are seem to exhibit different behavior as inferred from voltage profiles, time of burst, temporal optical emission profiles, and overheating factor (the ratio of energy deposited till burst to the enthalpy of atomization). Overheating in air is found to depend inversely on the enthalpy of atomization and resistivity for refractory and non refractory metals, respectively. Pd has shown mixed electrical and optical characteristics of both groups (refractory and non refractory) in air as well as in vacuum. On changing the surrounding medium from air to vacuum, overheating is found to decrease for all metals; interestingly, their drop is observed to depend on the speed of sound at room temperature in that particular metal. Using these experimental outcomes, the possible mechanisms responsible for energy diversion in the explosion of wires of different materials along with their correlation to surrounding medium are discussed in this work. In the present study, the electrical characteristics of gold have been found to be most favorable for efficient energy coupling and hence for high-energy-density applications irrespective of the surrounding medium.

中文翻译：

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六种金属丝在空气和真空中电爆行为的实验研究


已经进行了实验研究，以建立具有已知电学和热物理性质的不同金属快速电爆炸中能量耦合效率的相关性。为了涵盖广泛的金属特性，在本研究中，从两个众所周知的组（难熔金属和非难熔金属）中考虑了五种金属（金、铜、铝、钨和钛），并且钯被列为第六种金属，具有介于这两者之间的中间属性。对相同的电路参数（电流速率 $\approx \times 10^{9}$ A/s）进行比较研究，以探索这些金属在空气和真空两种不同介质中的电爆炸丝（EEW）行为。对这些金属线周围自发射光的时间演化进行分析，作为从金属芯到外日冕的能量转移的定性测量，并使用两种介质的条纹相机进行记录。在空气中，根据电压分布、爆发时间、时间光发射分布和过热系数（爆发前沉积的能量与原子化焓的比率）推断，难熔金属和非难熔金属似乎表现出不同的行为。发现空气中的过热分别与难熔金属和非难熔金属的雾化焓和电阻率成反比。 Pd 在空气和真空中表现出两种类型（难熔和非难熔）的混合电学和光学特性。当周围介质从空气变为真空时，所有金属的过热现象都会减少；有趣的是，观察到它们的下降取决于室温下特定金属的声速。 利用这些实验结果，本文讨论了不同材料的电线爆炸中能量转移的可能机制及其与周围介质的相关性。在本研究中，发现金的电特性最有利于有效的能量耦合，因此无论周围介质如何，都最有利于高能量密度应用。