铝丝电爆炸过程的光学诊断

Optical diagnosis of electrical explosion process of aluminum wire

采用100μm和40μm两种直径的铝丝,在不同放电电压下,通过分幅成像技术和光谱诊断方法,对铝丝电爆炸过程放电特性及放电等离子参数进行了诊断。实验研究表明:铝丝电爆炸过程中金属蒸气的二次击穿分为内部击穿和沿面击穿两种类型,较细的铝丝更容易发生内部击穿,发生内部击穿时产生的等离子体具有更好的空间均匀性和对称性,其放电过程具有更高的稳定性和可重复性。通过光谱诊断可知铝丝电爆炸等离子体电子温度在104 K量级,电子密度在1018 cm-3量级。

The discharge characteristic and plasma parameters of electrical explosion of aluminum thin wire were studied by framing camera and spectrograph.The experiments were carried out under several different discharge voltages with aluminum wires of 40 μm and 100 μm in diameter.The experiments show that there are two types of secondary breakdown processes in the metal vapor： inner breakdown and surface breakdown.The inner breakdown,which generates a plasma with better spatial uniformity and symmetry and consequently leads to more steady and repeatable discharge,takes place more easily in thinner wire under the same conditions.The electron temperature and density of the plasma have the order of magnitude of 104 K and 1018 cm-3,respectively.