The primary function of a bulletproof helmet is to safeguard against shrapnel. However, it cannot withstand a direct frontal impact from a bullet traveling at 450 meters per second within a 100-meter range. This implies that it offers protection against generally medium-powered pistols. The principle underlying its bulletproof design involves utilizing its semicircular shape to deflect the bullets. If the angle of impact is excessively positive, the bullet will strike the helmet head-on, making it incapable of transferring the bullet's force and leading to penetration. Historically, bulletproof helmets were called "helmets" due to their steel composition. Presently, they are made from nano-composites, which exhibit superior impact resistance compared to their steel counterparts while maintaining a weight approximately equal to 720 meters per second. These helmets can withstand the frontal impact of most rifle bullets. However, they are ineffective against certain small-caliber rifles such as China's 95-style rifle with a caliber of 5.8mm and an initial speed of 930 meters per second. No existing helmet has been able to block the 95-style rifle, but this only applies when the bullet strikes the helmet head-on. If the angle of impact is too large, the bullet will still ricochet off the helmet.
Bullet-proof helmets have gained popularity in recent years. They are designed with an anti-corrosive paint surface, ensuring a uniform outer appearance while also providing waterproof and moisture-proof functionality. This coating process enhances the helmet's stability, making it an important choice for many individuals. Moreover, the outer surface is coated to increase hardness and improve pressure and wear resistance, which is a primary reason for the growing preference for these helmets. The interior of the helmet features a mask lens assembly, which not only effectively protects the face and head but also allows for easy adjustment to ensure a comfortable fit. The use of a waterproof rubber strip in the mask further enhances its protective qualities and resists external impacts, making it a common and important choice. Overall, these advancements in design and materials have significantly improved the quality and performance of bullet-proof helmets, making them a compelling option for users.
