Boron Carbide
An extremely hard boron–carbon ceramic a covalent material used in tank armor bulletproof vests engine sabotage powders as well as numerous industrial applications
Boron carbide is a covalently bonded solid with a high melting point 2427°C outstanding hardness Vickers 3770 kg mm2 good mechanical properties and low specific gravity 2 52 g cm2 making it ideal for use in lightweight armours
Boron Carbide: A black solid, B4C,soluble only in fused alkali; it is extremelyhard, over 9? on Mohs’scale; rhombohedral; r.d. 2.52; m.p.2350°C; b.p. >3500°C. Boron carbideis manufactured by the reduction ofboric oxide with petroleum coke inan electric furnace. It is used largelyas an abrasive, but objects can also be fabricated using high-temperaturepowder metallurgy. Boron nitride isalso used as a neutron absorber becauseof its high proportion ofboron–10.
Uses:
- Boron carbide is a hard boron-carbon ceramic material used in tank armor, bulletproof vests, engine sabotage powders, neutron absorber, cutting tools and dies and in brake linings of vehicles. It acts as an antioxidant additives in magnesia-carbon bricks.
- It is used as a precursor in the production of boron containing materials such as titanium borideAbrasive. In the manufacture of hard and chemicals-resistant ceramics or wear-resistant tools. Finely pulverized B4C can be molded under (considerable) pressure and heat. The resulting products are very wear-resistant, such as pressure-blast nozzle liners, thread guides, extrusion dies, and all types of extremely accurate plug, snap, and ring gages. Powder is used as abrasive material, the molded article can be used for wear-resistant material, also used for nuclear reactor.
- It is used for grinding carbide, precious stones and other hard materials, grinding, drilling and polishing, metal boride manufacturing and smelting boron steel, boron alloys and special welding.Boron carbide (B4C) is produced by the hightemperature(about 1371 to 2482°C) interactionof boric oxide, B2O3, and carbon in an electricalresistance-type furnace. It is a black, lustroussolid.
- It is used extensively as an abrasive,because its hardness approaches that of the diamond.
- It is also used as an alloying agent, particularlyin molybdenum steels.
Physical Properties:
| Melting point | 2450°C |
| Boiling Point | 3500°C |
| Density | 2.51 g/mL at 25 °C (lit.) |
| Solublity | insoluble in H2O, acid solutions |
| Form | Powder |
| Colour | Black |
| Specific gravity | 2.51 |
| Resistivity | 4500 (ρ/μΩ.cm) |
| Water solublity | Insoluble in water |
| Stability | Stable. Incompatible with oxidizing agents. Not flammable. |
| insoluble in H2O, acid solutions |
| insoluble in H2O, acid solutions |
