Boron Carbide
Boron Carbide
| Other names | Tetrabor |
| Cas No. | 12069-32-8 |
| Chemical formula | B4C |
| Molar mass | 55.255 g/mol |
| Appearance | Dark gray or black powder, odorless |
| Density | 2.50 g/cm3, solid. |
| Melting point | 2,350 °C (4,260 °F; 2,620 K) |
| Boiling point | >3500 °C |
| Solubility in water | Insoluble |
Mechanical Properties
| Knoop Hardness | 3000 kg/mm2 | |||
| Mohs Hardness | 9.5+ | |||
| Flexural Strength | 30~50 kg/mm2 | |||
| Compressive | 200~300 kg/mm2 | |||
Enterprise Specification for Boron Carbide
| Item No. | Purity(B4C %) | Basic Grain(μm) | Total Boron(%) | Total Carbide(%) |
| UMBC1 | 96~98 | 75~250 | 77~80 | 17~21 |
| UMBC2.1 | 95~97 | 44.5~75 | 76~79 | 17~21 |
| UMBC2.2 | 95~96 | 17.3~36.5 | 76~79 | 17~21 |
| UMBC3 | 94~95 | 6.5~12.8 | 75~78 | 17~21 |
| UMBC4 | 91~94 | 2.5~5 | 74~78 | 17~21 |
| UMBC5.1 | 93~97 | Max.250 150 75 45 | 76~81 | 17~21 |
| UMBC5.2 | 97~98.5 | Max.10 | 76~81 | 17~21 |
| UMBC5.3 | 89~93 | Max.10 | 76~81 | 17~21 |
| UMBC5.4 | 93~97 | 0~3mm | 76~81 | 17~21 |
What is Boron Carbide(B4C) used for?
For its hardness :
The key properties of Boron Carbide, which are of interest to the designer or engineer, are hardness and the related abrasive wear resistance. Typical exampleS of the optimum use of these properties include: Padlocks; Personal and vehicle anti-ballistic armor plating; Grit blasting nozzles; High-pressure water jet cutter nozzles; Scratch and wear resistant coatings; Cutting tools and dies; Abrasives; Metal matrix composites; In brake linings of vehicles.
For its toughness:
Boron carbide is used to make as Protective Armors to resist the impact of sharp objects like bullets, shrapnel, and missiles. It is usually combined with other composites during processing. Because of its high toughness, B4C armor is difficult for the bullet to penetrate. B4C material could absorb the force of the bullet and then dissipates such energy. The surface would shatter into small and hard particles later. Using boron carbide materials, soldiers, tanks, and airplanes could avoid serious injuries from bullets.
For other properties :
Boron carbide is an extensively used control material in nuclear power plants for its neutron-absorbing ability, low price, and abundant source. It has a high absorption cross-section. The ability of boron carbide to absorb neutrons without forming long-lived radionuclides makes it attractive as an absorbent for neutron radiation arising in nuclear power plants and from anti-personnel neutron bombs. Boron Carbide is used to shield, as a control rod in the nuclear reactor and as shut down pellets in a nuclear power plant.