Analysis On Performance Of UHMWPE Multi-shock Shield

Studying impact protection is vital to weaponry system and spacecraft in space environment.A large number of studies show that the projectile has different damage effects on the shield under different impact velocities.Thus,shield technologies for different impact speeds are generated.Among them,shield technologies for ultra-high speed impact(above 3km/s)represented by whipple structure and shield technologies for low speed impact(below 1.3km/s)represented by composite armor have been developed and widely applied in engineering.However,for the high-speed impact with velocity of 1.3km/s～3km/s.the research on the corresponding shield technologies is still immature,and there are almost no engineering application examples.In recent years,with the development of a series of kinetic energy weapons,the impact threat of 1.3km/s～3km/s is increasing,which puts forward new requirement for corresponding shield technologies.At the same time,the research on high-strength and light-weight shield materials(such as aramid and UHMWPE,etc.)is constantly developing and improving,with more and more engineering applications.It is of great significance to consider such materials for high-speed impact shielding.In this paper,the finite element model of ultra-high molecular weight polyethylene(UHMWPE)is established by sub-laminate modeling method.The model is modified based on the high speed experiment results of UHMWPE shield.Through the modified model,the impact protection characteristics of multi-plate UHMWPE shield are studied.The main research conclusions are as follows:(1)Confirm the accuracy of the model by comparing the simulation results with the experimental onesConfirm the related material parameters,equation of state and the criteria of failure by researching relevant literature.Refer to the result of single panel UHMWPE impact experiment to guarantee the accuracy of the model.Verify the accuracy of the model setup by data such as the size of the bulge,diameter of the bullet hole,residual velocity of the projectile.The final simulation results differ within 11% from the quantitative data of the experiment results.(2)Based on the modified simulation model,the two-plate shield is established and its shielding characteristics were studiedThe parameters of the simulation model modified by the experimental results were used to establish the two-plate structure simulation model.The difference of shielding effect between single-plate and double-plate shield of the same surface-density under impact velocity of 0.5km/s～3km/s was studied.The results show that when the impact velocity was more than 2km/s,the shielding performance of the two-plate shield is significantly better than that of the single-plate shield,and the shielding performance reaches the peak when the distance between the two-plate shield reaches 10 cm.(3)Based on the modified simulation model,the three-and four-plate shield models are built and their performance is studied.The simulation model of multi-plate shield is built using the simulation model parameters modified by the experimental results.The performance of the three-and four-plate shield with the same surface-density under impact velocity of 0.5km/s～3km/s is studied.The results show that the uniform spacing is beneficial to improve the performance of the multi-plate shield.At the same time,shield with more separate plates performs better under impact velocity above 2km/s.