冲击载荷作用下两种HMX基抗高过载炸药损伤特性

摘要

为研究炸药在高过载条件下的损伤特性及损伤破坏机理,选取两种不同成型工艺下(浇注,压装)的奥克托今(HMX)基抗高过载炸药作为研究对象,用冲击波感度试验对炸药进行冲击损伤,通过CT检测表征试验前后炸药的损伤程度,同时测试了冲击损伤后炸药的冲击波感度.CT检测结果表明,冲击损伤后压装成型炸药各观测界面均未出现宏观损伤,而浇注成型炸药在距见证板一端7～8 mm位置,出现了长度7～8 mm、直径1～2 mm的孔洞,浇注炸药在距离下端面40 mm以上,损伤后的CT值降低1％ ～5％,压装炸药在距离下端面50 mm以上,损伤后的CT值升高1％ ～8％.冲击损伤后两种炸药的冲击波感度均降低,其中浇成型注炸药由未损伤时的临界隔板厚度25 ～27 mm下降到13～15 mm;压装成型炸药由未损伤时的临界隔板厚度38～40 mm下降到30·32 mm.%Two kinds(casting moulding and pressed fitting) of HMX-based anti-overloaded explosives were chosen to study the damage characteristics and damage failure mechanisms of explosives under overloaded conditions by shock loading.The shock damage was conducted based on shock wave sensitivity test.The damage characteristics of samples before and after shock loading were studied by CT and the shock wave sensitivity was also tested after damage.Results of CT test show that no macro-damage appear in explosive by pressed fitting after the shock damage,while a cavity with length of 7-8 mm and diameter of 1-2 mm appears in cast explosive and is located at 7-8 mm away from one end of the witness board.After shock damage experiments,for cast explosive,above the position of 40 mm from the bottom surface,the explosive density decrease by 1％-5％,and for the pressed fitting explosive,above the position of 50 mm from the bottom surface,the explosive density increase by 1％-8％.The shock wave sensitivity of the both samples decreases after shock damage.The critical gap thicknesses of the cast explosive decreases from 25-27 mm before damaged to 13-15 mm after damaged,while for pressed fitting explosive,the thickness decrease from 38-40 mm to 30-32 mm.