高钝感半导体桥发火性能研究

为了提高半导体桥（SCB）火工品的安全性，在SCB极脚间并联负温度系数（NTC）热敏电阻，可使NTC-SCB半导体桥满足1.5 A不发火、最高2.0 A不发火的高钝感要求。研究了1.0 A和 1.5 A通电条件下NTC热敏电阻与SCB并联后的分流情况，通过电容放电、恒流激励下的发火实验和发火感度实验对比分析了SCB、NTC-SCB和1.5 A、2.25 W、5 min安全电流实验后的NTC-SCB半导体桥发火性能。结果表明：在1.0 A、1.00 W、5 min和1.5 A、2.25 W、5 min安全电流实验条件下，NTC热敏电阻的分流比约为35%和62%，达到热平衡时的温度大约为112 ℃和170 ℃； 在33 μF、30 V电容放电条件下并联NTC热敏电阻及1.5 A、2.25 W、5 min安全电流实验后，SCB的发火时间和临界发火能量均没有出现显著性变化；在7.0 A恒流激励下，由于输入能量速率较慢以及NTC热敏电阻分流的原因，发火时间和临界发火能量均有较明显提高；SCB的99.9%发火电流在并联NTC热敏电阻后从2.329 A增加到3.709 A，NTC-SCB的99.9%发火电流在1.5 A、2.25 W、5 min安全电流实验后从3.709 A增加到4.285 A，仍然可用于提供大于5.571 A电流的火工装置。

Research on the Ignition Performance of High Insensitive Semiconductor Bridge

A negative temperature coefficient (NTC)-semiconductor bridge (SCB) was prepared to improve the safety of SCB explosive initiator by paralleling a NTC thermistor to SCB, which is able to meet the requirement of high insensitiveness in 1.5 A and maximum 2.0 A non-firing stimuli tests. The split ratios at 1.0 A and 1.5 A after paralleling NTC thermistor to SCB were analyzed. Capacitance discharge ignition test, constant current excitation test and ignition sensitivity test were made to study the ignition performances of SCB, NTC-SCB and NTC-SCB after 1.5 A, 2.25 W and 5 min safe current test. Results show that the split ratios of NTC thermistor are about 35% and 62%， and thermal equilibrium temperatures are about 112 ℃ and 170 ℃ in 1.0 A, 1.00 W and 5 min, and 1.5 A, 2.25 W and 5 min safe current test, respectively. The ignition time and critical ignition energy are not show significant changes at 33 μF/30 V, but significantly increase at 7.0 A due to slow energy input rate and NTC thermistor shunt. Furthermore, 99.9% firing current of NTC-SCB increases from 2.329 A to 3.709 A after paralleling NTC thermistor and further increases from 3.709 A to 4.285 A after 1.5 A, 2.25 W and 5 min safe current test, which can be applied to the devices with ignition current greater than 5.571 A.