Electrothermal Discharge by Exploding of Copper Wires with Different Diameters

Wire explosion is of a major importance in different applications. The present work studies the explosion of copper wires of different radii. This process was achieved by the discharge of a capacitor bank of total energy up to 1.11 kJ. The variation of the various electrical properties of the copper wires was calculated as a function of the discharge time, the wire temperature, and the wire diameter. The Shomate equation was used to calculate the specific heat capacity of the copper wires as a function of temperature, while the wire resistivity was calculated using a fitting equation based on data extracted from published references. It was found that the time needed for the wire explosion decreases with increasing charging voltage while it increases with an increase of the wire diameter. As the discharge occurs, the wire temperature raises, causing both the specific heat and the wire resistivity to increase. The specific action integral was found to be about 2.1 × 10 ⁹ A ² .s/cm ⁴ for all wire diameters. Also, the resistance was increased by approximatelly 9.2% due to the thermal expansion of the wires.