Crystalline Boron Powder
It is a high-purity, hard and high-temperature resistant metalloid powder.
1. Basic Information
Appearance: Greyish black / jet black lustrous powder, mainly stable beta-rhombic crystal form
Purity: 96%–99.99% (commonly 99%, 99.9%)
Particle size: Micron grade (e.g. 300 mesh), ultra-fine and nano grade available on request
2. Core Physical & Chemical Properties
Density: 2.34–2.37 g/cm³
Melting point: 2300℃±2℃
Sublimation point: 2550℃
Hardness: Mohs hardness 9.3, second only to diamond
Solubility: Insoluble in water, ethanol, ether and hydrochloric acid; soluble in cold concentrated alkali solution (releasing hydrogen), hot concentrated nitric acid / concentrated sulfuric acid (oxidized into boric acid)
Stability: Stable at room temperature; oxidizes at 300℃ and combusts with red flame at 700℃
3. Crystalline vs Amorphous Boron Powder
- Crystalline Boron: Long-range ordered lattice (B₁₂ icosahedron); high hardness, high melting point, low activity and excellent high-temperature oxidation resistance; produced by slow cooling above 1800℃
- Amorphous Boron: Disordered structure; high activity, easy to oxidize, manufactured at low temperature; lower cost for general usage
4. Main Applications
- Military & Aerospace: High-energy fuel for solid rocket propellants, neutron absorber and shielding materials for nuclear reactors
- Metallurgy: Deoxidizer for special steel and oxygen-free copper, additive for magnesia carbon brick, raw material for metal borides
- Electronics & Semiconductors: High-temperature semiconductors, igniter tube electrodes, copper boride cathode materials
- Ceramics & Composite Materials: Wear-resistant ceramics, bulletproof armor, reinforcing phase for high-temperature resistant coatings
5. Packaging, Storage & Transportation
Storage: Keep in cool and dry place, sealed and moisture-proof; keep away from strong oxidants and strong acids