Bulletproof Hard Plate AL2O3 Ceramic Sheet NIJ III ICW

A: This stems from the completely different energy dissipation mechanisms of the two materials:
• Steel Plate Principle (Plastic Deformation and Energy Dispersion): Relying on its extremely high surface hardness (HRC 500 and above), the bullet is "passivated" or "shattered." During this process, the steel plate itself dents, absorbing and dispersing kinetic energy through large-area plastic deformation.
• Disadvantages: The energy transfer ratio is still relatively high, easily causing severe back convex injuries; the shattered bullet core and steel plate fragments may form secondary fragments.
• Ceramic Composite Plate Principle (Brittle Fracture and Momentum Transfer): The surface ceramic (such as boron carbide and silicon carbide) has extremely high hardness, but is brittle: When the bullet hits, its extremely high hardness directly "shatters" the bullet ("pulverizing" the metal bullet).
• Momentum Transfer and Fracture: Simultaneously, a "fracture cone" forms below the impact point of the ceramic, resulting in large-area shattering. This process consumes the vast majority of the energy.
• Backplate trapping: The ultra-high molecular weight polyethylene or aramid backplate acts like a highly resilient net, enveloping and trapping ceramic fragments and deformed projectile debris, preventing penetration and further absorbing residual energy.
• Conclusion: The ceramic system, by "sacrificing itself" (fragmenting), more efficiently converts the bullet's kinetic energy into the internal energy of the fragmented material, thus achieving protection with a lighter weight. The steel plate, on the other hand, absorbs energy through its own "bearing" and deformation.