In order to analyze the composition and frequency distribution of acceleration signal in the process of projectile penetrating,this paper uses wavelet transform to decompose penetration acceleration signal to get the distribution of penetration acceleration signal in different frequency bands.Compared with the ideal acceleration signal curve and its characteristics,it can be concluded that the frequency range of the acceleration signal in the axis of the projectile and the vibration frequency range of the projectile are 31.25-62.5kHz and 62.5-125 kHz,respectively.Finally,the penetration acceleration signal curve is obtained by Simulink.
In order to make unexploded ordnance lose explosive ability,the chemical failure of HMX that is usually used as detonating explosive and booster was studied so as to find the corresponding chemical reagents,which can decompose HMX into compounds without explosive properties.For this purpose,several decomposition experiments between HMX and NaOH,HMX and thick H2 SO,HMX and mixed acid under different temperature conditions were carried out.According to the experimental results,it can be concluded that HMX can be decomposed by a mixture of concentrated nitric acid and concentrated nitric acid with the volume ratio of 3∶1.When its decomposed level reaches 60%,HMX will not be detonated,therefore the failure purpose is achieved.
