Simulation And Analysis Of Shrapnel Materials Crushing Process

The projectile lethality mainly associated with the projectile blasting fragment rate. In order to increase the rate of the projectile warheads, the study of projectile shell has become the important content of military industry. In this subject, the brittle zone was machined on the surface of the shell of the projectile by means of laser quenching processes, to exam whether the existence of the brittleness on the shell surface could achieve the effect that enhance the projectile damage, and improve the missile body’s utilization rate of precontrol fragment of the shell.The subject mainly divided into three parts. In the first part, there were three kinds of materials which were 40 Cr, 58 SiMn, 50 SiMnVB set up as the shell material to build the projectile models, then processed brittle zone on these shells in order to simulate the projectile blasting situation. Through comparing the work curves of internal energy absorption of projectile blasting with brittle object or not. It concluded that the internal energy absorption function of projectile shell with brittle is far less than that without brittle shell absorption function, this situation proved that the shell with brittle is more likely to be ruptured, and the fragment size is more averaged, and the projectile has bigger piece broken rate. Chose different elements in the projectile shell of brittle zone, the change of the stress wave near the fragile belt element was bigger by observing stress wave drawing, this suggested that the shell is more likely to fracture from the brittle belt, and caused shell fracturing. In the second part, this subject selected 58 SiMn for shell material, and established brittle zone that with different depth and width on the surface of shells and simulated this kind of projectiles. In the practical permissible range, the results showed that the projectile shell with brittle that the deeper the depth, the wider the width, the projectile shell is easier to be broken, and the fragment size distribute averaged, the projectile has larger fragment rate and bigger lethality. Through multiple sets of brittle zone that had the same width with different depth or different width with the same depth of the same model to simulate the projectile explosion, and finally got different internal energy work curve when the depth or the width of brittle changes. Judged by the graph, it concluded that the broken shell absorption function is smaller, and the shell is more easily to be broken when raise the depth of brittle, the broken shell absorption function is smaller, and the shell is also more easily to be broken when raise the width of brittle. In the third part, the main stimulation process wasto stimulate fragment of penetrating the target plate process. In this section, through changing the depth of brittle to simulate the projectile blasting, and then measure the fragment velocity in order to stimulate fragment of penetrating the target plate process.Finally, it is concluded that the deeper the depth of brittle, the bigger the fragment velocity,the greater the penetration the residual velocity of the fragment, and the greater the fragment lethality.This paper also used laser surface treatment processing processes brittle zone of different density in the 58 Si Mn veneer, and impact testing machine was used for impact crushing experiments. The results showed that the plate with brittle zone fracture along the brittle after impacting plate, and the fracture is neat, in addition that the fracture of shell with brittle absorbed internal energy is less than the fracture of shell without brittle absorbed by comparing shell plate with brittle zone or not. The subject also used laser surface treatment machines to process brittle zone on the projectile shell surface, the shape of a projectile exploded fragment was observed. The result showed that after the explosion, the fragments of the projectile shell with brittle size are more averaged, and the fracture surface is neat, the shapes generally are rectangle that are similar to the shape of the brittles before exploded.This kind of projectile had greater lethality and higher broken piece rate.