Ultra high molecular weight polyethylene

Ultra high molecular weight polyethylene (UHMWPE)

Ultra high molecular weight polyethylene fibers (molecular weight ≥ 3 million g/mol) are woven and hot pressed into fiberboard, which is currently the mainstream core substrate for bulletproof backboards. Combined with alumina, silicon carbide, and boron carbide bulletproof ceramics to form ceramic composite armor, it can also be separately made into soft bulletproof vests and is an indispensable material for bulletproof systems.

1、 Bulletproof mechanism

Soft fabric: When a bullet hits the fiber layer, the ultra-high strength polyethylene fibers quickly stretch, slip, and layer by layer tear, dispersing the impact energy to a large area of the fabric, absorbing the energy of the bullet through fiber breakage and deformation, and preventing the bullet from penetrating;

Composite armor backplate: After the ceramic shatters the bullet, the remaining core and shattered ceramic pieces impact the PE backplate. The high-density hot pressed PE sheet is wrapped around the fragments through multi-layer fiber stretching and plastic deformation to prevent splashing and prevent blunt injuries to the human body caused by excessive back protrusion.

2、 Product Form Classification

1. Soft UD bulletproof cloth

Non hot pressed soft film, multi-layer laminated seam bulletproof vest, made of pure soft UD fabric, can achieve NIJ Ⅲ A grade bulletproof vest, defend against various handgun bullets and fragments, weigh much better than aramid, and be resistant to moisture and seawater.

2. Hot pressed hard PE sheet

Industrial hot pressing solidifies into high-density hard boards, and ceramic bulletproof inserts come with a standard backplate with a thickness of 6-12mm, which is bonded and compounded with bulletproof ceramic sheets to form a 'ceramic surface layer+PE backplate' standard bulletproof structure, achieving protection against rifle bullets at levels III and IV.

3. Molded irregular parts

Hot pressed molded curved sheet metal is used for the lining of bulletproof helmets, shoulder armor, crotch protection and other shaped protective components.

3、 Segmented application areas

(1) Individual protection (maximum usage)

Soft bulletproof vest: Made of full UD fabric bulletproof vest, suitable for daily wear by public security patrol officers and border guards, capable of withstanding 9mm Parabellum,. 44 Magnum bullets, and explosive fragments; Moist and rainy, coastal and rainforest environments are better than aramid.

Ceramic composite bulletproof insert board: 99 alumina, silicon carbide, boron carbide bulletproof ceramic tiles are bonded with hot pressed PE board on the back to make a grade III/IV chest insert board, which can resist 7.62 ordinary bullets and steel core armor piercing bullets. The UD backplate effectively reduces the concave value of the back and reduces blunt impact injuries, making it a universal matching structure for global military and police standard plug-in boards.

Bulletproof helmet: outer fiberglass/PE shell+inner UD lining layer, resistant to pistol bullets, shell fragments, and debris impact; Lightweight helmets often use fully molded UD integrated molding.

Limb protection: tactical shoulder, waist, and calf protection pads.

(2) Vehicle mounted lightweight armor

Cash transport vehicles and special police explosion-proof vehicles: The inner wall layer of the carriage is made of multi-layer UD composite armor, which is used in conjunction with ceramic blocks to replace heavy steel plates, greatly reducing the weight of the entire vehicle; Light wheeled armored vehicles are equipped with additional lining to resist fragments and long-range machine gun bullets, and are commonly used for lightweight protection of logistics vehicles and command vehicles.

(3) Security engineering and special protection

The guardrails, bulletproof partitions, and vault protective doors are filled with UD panels, combined with alumina ceramic tiles to form a composite bulletproof wall; The backboard of the shooting range relies on UD to absorb the residual kinetic energy of bullets.

(4) Lightweight protection for ships and helicopters

Ship cabin partition walls and helicopter cabin liners, UD is resistant to seawater salt spray and moisture, with minimal performance degradation in high humidity marine environments, used to protect against explosive fragments and scattered bullets.

4、 Core advantages of materials

Extremely low density, floating in water, with an equivalent protective weight of only 1/8 of steel and 1/4 of alumina ceramic, making it extremely lightweight;

Hydrophobic and non absorbent, the bulletproof performance hardly deteriorates after immersion, superior to aramid, suitable for islands, rainy southern regions, and humid coastal environments;

Excellent low-temperature resistance, maintaining mechanical properties even at minus 40 ℃, making it the preferred equipment for high-altitude regions;

Resistant to acid and alkali corrosion, not moldy, not easily aged, and has a long storage and service life.