金属隔层和空气间隙对钝感炸药冲击起爆的影响

为了确定空气间隙和金属隔层对冲击起爆的影响,采用火炮加载蓝宝石飞片冲击起爆Φ50 mm×30 mm的A型炸药,产生的冲击波通过空气间隙和金属隔层起爆Φ50 mm的台阶型B型炸药。在B型炸药的后界面粘贴镀膜氟化锂(LiF)窗口,使用光子多普勒测速仪(PDV)测量金属和B型炸药的后界面速度,进而计算得到金属和B型炸药的冲击波透射压力,再利用阻抗匹配计算得到金属和B型炸药的入射压力。结果表明:传爆药和金属隔层间的空气间隙使冲击压缩过程转变为准等熵压缩和冲击压缩两个过程,同时使冲击波的幅值减小;确定了金属隔层厚度为5 mm时冲击波压力的衰减范围;当使用A型炸药作为传爆药,空气间隙为0.3 mm,金属隔层厚度为5 mm时,B型炸药在7~10 mm之间开始反应。

Effects of Metal Interlayer and Air Gap on the Shock Initiation of Insensitive Explosives

The influences of air gap and metal interlayer on the shock initiation of theΦ50 mm stepped explosive B have been investigated by means of the sapphire flyer planar impact experiment and photonic doppler velocimetry(PDV)technique.In the experiment,a lithium fluoride(LiF)window was stuck to the rear interface of explosive sample to allow the rear interface velocity between the metal and the sample explosive be measured by PDV technique.Both the transmission shock pressure and the incident shock pressure can be obtained by the impedance-match method.The experiment results have shown that the air gap divided the impact compression process into quasi-isentropic compression and impact compression,respectively,and at the same time,the amplitude of the shock pressure was declined.Specifically,the shock wave attenuation range caused by 5 mm thick metal was achieved.When the explosive A was used as the booster,and with a 0.3 mm thick air gap and 5 mm thick metal experimental setup,the reaction of sample explosive B started in a range from 7 mm to 10 mm.