Research On Bionic Bulletproof Equipment Based On The Penetration Inhibition Function Of Tetraodon Mbu Teeth

With the rapid development of science and technology,local conflicts and terrorist attacks occur from time to time.Protective equipment plays an indispensable role in protecting the wearers’life safety and improving operations’flexibility.With the diversification of combat methods and the rapid development of weapons and equipment,the risk of soldiers being attacked by projectiles and high-speed fragments is increasing,which seriously threatens the life safety of the wearers.At present,it is difficult to meet the actual needs of lightweight protective equipment and high protective performance with traditional methods.Therefore,it is urgent to develop modern protective equipment that is convenient to wear and has high protective performance.Nowadays,the development of lightweight,high protective performance of personal protective equipment has become the focus of research researchers.Creatures in nature adapt to the complex environment around them with excellent shock resistance strategies and unique defense mechanisms.The unique impact resistance and energy dissipation mechanism of organisms provide a certain reference for researchers to design and manufacture protective devices with excellent performance.In this paper,starting from the need to improve the bulletproof performance of bulletproof baffles in modern protective equipment and drawing on the bionic idea,the excellent performance of Tetraodon mbu teeth is selected as the bionic prototype,the realization mechanism of the anti-penetration protection function of Tetraodon mbu teeth is revealed,the key characteristic parameters of Tetraodon mbu teeth are extracted,and a new bionic anti-penetration protection model is established.The bullet-proof mechanism of the bionic sample was explored by combining finite element analysis with a ballistic experiment.The main research contents and results are as follows:In this paper,Tetraodon mbu was selected as the bionic prototype.Firstly,the surface structure,geometric shape and sectional morphology of Tetraodon mbu teeth were characterized and analyzed by micro-computed tomography,ultra-depth of field optical microscope,type microscope and scanning electron microscope.It was found that the joint of two adjacent teeth of Tetraodon mbu teeth showed a unique zigzag multistage"suture"interface structure.Tetraodon mbu teeth are mainly layered materials composed of enamel and dentin.Through further analysis of the internal structure of teeth,it is found that the basic structure of tooth enamel is enamel columns,which are closely arranged to share the stress,so that the outer enamel of the tooth is not easy to fall off and the internal structure is not destroyed.The dentin of Tetraodon mbu teeth is composed of several dentin bands with dentin pores inside the dentin pores.When the crack extends to the dentin pore,the crack will deflate around the dentin pore to some extent,thus increasing the fracture toughness of the tooth.At the same time,multiple dentin bands and dentin pores can slow down the stress,slow down the degree of tooth breakage and protect the integrity of teeth.The unique internal structure of the enamel and dentin region has a certain influence on the function of inhibiting penetration.The chemical composition of teeth of Tetraodon mbu was analyzed by X-ray energy spectrum,X-ray diffractometer and Fourier infrared spectrometer,and the differences in chemical composition and content in teeth of Tetraodon mbu were investigated.The elastic modulus and hardness of tooth enamel and dentin of Tetraodon mbu were investigated by nano-indentation instrument.It was found that the mechanical properties of the teeth of Tetraodon mbu were different in different regions.The mechanical properties of the teeth showed a gradient change,and the elastic modulus and hardness decreased gradually from the enamel region to the dentin region.Based on the characterization and analysis of the macroscopic and microscopic morphology,chemical composition and nanomechanical properties of the teeth of Tetraodon mbu,the mechanism of the anti-penetration protection of Tetraodon mbu teeth was revealed.It was found that the excellent anti-penetration protection function of Tetraodon mbu teeth was the result of the synergistic effects of various factors.On this basis,key characteristic parameters such as columnar structure,pore structure and gradient stratified structure of Tetraodon mbu were extracted to establish a bionic penetration resistance model.The process of penetration of the bionic target plate by type 53 7.62mm armor-piercing incendiary bomb was simulated by ANSYS/LS-DYNA software to analyze the damage process of the bionic target plate and explore its ballistic protection performance.It provides a reference for the improvement of ballistic protection performance of protective equipment.On the basis of numerical simulation,bionic samples of two structures were designed and manufactured,and ballistic experiments were carried out on the two bionic samples and flat plate samples respectively with type 53 7.62mm armor-piercing incendiary bomb.Damage conditions of each layer material of the two bionic samples and flat plate samples were compared and analyzed,and the role of each layer material of the bionic sample in the actual projectile penetration process was explored.The bulletproof mechanism of the bionic sample is further explored.It is found that compared with the flat sample and the bionic sample S₁,the bionic sample S₂ can effectively resist projectile penetration and has better bulletproof performance.The elastic resistance of the bionic sample S₂ is mainly the result of the synergistic action of multiple layers and multiple materials,such as a ceramic panel composed of single-side arc ceramic columns arranged in a close stack structure,titanium alloy support layer,aluminum foam buffer energy absorption layer and UHMWPE layer.Compared with the flat sample,after a single projectile impact,the bionic sample S₂’s broken area of the ceramic panel is reduced by about 56%and the BFS value is reduced by about5.2%after being penetrated by the projectile.There is no splashing of ceramic fragments in the process of projectile target action,which will not cause secondary damage to human body or surrounding objects.At the same time,the damaged area of the ceramic layer is small,and it still has a good resistance to projectile impact when it is penetrated again.The bionic target plate has a certain ability to resist multiple projectile impacts.