Abstract:To verify the scientific hypothesis that the phase-transition lag of Al/CuO composite film enables temporal coupling of electrothermal and chemical energy and reduces the energy demand for gap ignition, a finite element model of an Al/CuO energetic semiconductor bridge (ESCB) was established with pure polycrystalline silicon SCB simulation as the control baseline. Using capacitance (27, 47, 100 μF) and voltage (40, 45, 50, 66.7, 34.6 V) combinations as design variables, the heat transfer process, plasma flow field evolution, and gap ignition mechanism during ESCB ignition were systematically investigated. The results show that current density concentrates at the V-shaped corner of the bridge region, triggering phase transition preferentially; the temperature rise of the Al/CuO film exhibits an obvious lag of approximately 17.3 μs relative to the polysilicon film, enabling the plasma channel to establish prior to the aluminothermic reaction, after which chemical energy is continuously injected, achieving temporal coupling of electrothermal and chemical energy. Compared with the pure SCB, the peak temperature increases by 31% and the electron density by 87%. Under excitation of 47 μF and 50 V, the energy utilization rate reaches 55.83%, and reliable 1 mm gap ignition is achieved. Based on simulation and experimental results, design guidelines of "structural zoned deposition, energy temporal matching, and simulation pre-screening" are proposed for ESCB, providing an engineering basis for low-energy reliable gap ignition.
