As far as the projectile is concerned, its kinetic energy, shape, and material are important factors determining its penetration force. Ordinary warheads, especially lead core or ordinary steel core bullets, will deform when in contact with bulletproof materials. During this process, a considerable amount of kinetic energy is consumed by the bullet, effectively reducing its penetration force, whic
Factors Affecting the Bulletproof Effectiveness of Bulletproof Vests
The factors that affect the bulletproof effectiveness of bulletproof vests can be considered from two aspects: the projectile (bullet or fragment) that interacts with each other and the bulletproof material.
As far as the projectile is concerned, its kinetic energy, shape, and material are important factors determining its penetration force. Ordinary warheads, especially lead core or ordinary steel core bullets, will deform when in contact with bulletproof materials. During this process, a considerable amount of kinetic energy is consumed by the bullet, effectively reducing its penetration force, which is an important aspect of the bullet's energy absorption mechanism. For the fragments produced during explosions such as bombs and grenades, or the fragments formed by bullets, the situation is significantly different. These fragments have irregular shapes, sharp edges, light weight, small volume, and do not deform after hitting bulletproof materials, especially soft bulletproof materials.
Generally speaking, the speed of such fragments is not high, but they are large and dense. The key to absorbing energy from such fragments in soft bulletproof vests is to cut and stretch the yarn of the bulletproof fabric, causing it to break, and to cause the interaction between the yarns inside the fabric and between different layers of the fabric, resulting in overall deformation of the fabric. During these processes, fragments do external work, thereby consuming their own energy.
In the process of deformation and absorption of projectile energy in the two types of bulletproof vests mentioned above, a small part of the energy is also converted into thermal energy through friction (fibers/fibers, fibers/bullets), and into sound energy through impact.
As for material, differences in single fiber utilization and overall elongation and deformation ability of different UHMWPE fibers will affect the performance of bulletproof vessels The fine finesse of the bullet proof material fibers results in a tier fit in the UD fabric of vessels and a more uniform force distribution, improving the strength of the UD fabric and protective ability of vessels In addition, the straightness and parallelism of fiber arrangement, the number of inner and outer layer transfers, and yarn twist all have important effects on the mechanical properties of UD fabric, specifically tense strength and association at break.