Boron carbide
Boron carbide is a chemical compound with the formula B4C. It is an extremely hard ceramic. It is often used as an abrasive, as armor, as a scratch-proof coating, as a neutron absorber in the control rods of nuclear reactors, and as an additive in the cut-resistant shackle in some padlocks.
Boron Carbide Media
Unit cell of B4C. The green sphere and icosahedra consist of boron atoms, and black spheres are carbon atoms.
Plastic embedded with boron carbide used as shielding in neutron experiments at the Atomic Energy Research Establishment, UK
Boron carbide is used for inner plates of ballistic vests