What are The Factors Influence Bulletproof Effect?
2016-05-06 08:13 | writer: admin
For fabrics, bulletproof effect related to 5 factors of the fabrics:
1. The fineness of fiber
The fiber fineness is more small, they are more closer to each other in the yarn, the stress is more even, thus increase the strength of yarn, meanwhile, the bulletproof performance of fiber material are increased
2. Fiber’s physical such as tensile strength, modulus, tensile elongation and fracture work
Ideally, the material with high tensile and high elongation strain ability have big potential of energy absorption. But in practice, the material used for bulletproof clothing do not allow excessive deformation, otherwise it will cause serious non-penetratins trauma. So the fiber material used for bulletproof clothing requests higher elasticity modulus at the same time.
3. The collection method of fiber
Yarn is the collection of fiber, the fracture process of it is big different from the fiber.The fiber’s extended parallelization of permutation, the transfer frequency of inside and outside layer, yarn twist are all influence the mechanical property of fabric, especially tensile strength and tensile elongation etc.. So as fewer as possible to add yarn twist and even do not add yarn twist, so can fully improve the utilization rate of fiber.
4. The construction of fabric
In theory, if want to get good shock resistance, should use UD technical material which is unidirectional and without crossing point. The fabric adopts this technique also be called unidirectional fabric. The most energy of bullet or shrapnel can be absorbed by fiber elongation and fracture at or nearby the shock point. In other words, the unidirectional fabric eliminates the fabric’s stress wave reflection and negative effect, make the energy of stress wave outward spread faster, to improve the bullet-proof performance significantly. Meanwhile, parallel arrangement of the fiber structure also can greatly enhance the overall utilization of the fabrics.
5. The surface feature of yarn
After smooth surface and low friction coefficient of fiber is impacted by the bullet, the ability to transfer energy between fibers is decreased, stress wave can’t spread quickly, so reduce the capability of the fabric sniper bullets. The exit of oil agent and water on the surface of yarn also can reduce the resistance that the bullet or shrapnel pierce materials, so usually need do wash and dry process to the bulletproof material to improve the frictional resistance on the surface of the materials.