Damage Characteristics of Two HMX based Anti-overloaded Explosives under Shock Loading

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 of7-8mm and diameter of1-2mm appears in cast explosive and is located at7-8mm away from one end of the witness board.After shock damage experiments,for cast explosive,above the position of40mm from the bottom surface,the explosive density decrease by1%-5%,and for the pressed fitting explosive,above the position of50mm from the bottom surface,the explosive density increase by1%-8%.The shock wave sensitivity of the both samples decreases after shock damage.The critical gap thicknesses of the cast explosive decreases from25-27mm before damaged to13-15mm after damaged,while for pressed fitting explosive,the thickness decrease from38-40mm to30-32mm.