morphous Boron Powder: Core Powder Raw Material for High-Performance Neutron-Absorbing Composites
Product Name: Amorphous Boron Powder
CAS: 7440-42-8
1. Product Overview
Amorphous boron powder is non-crystalline elemental boron without long-range ordered crystal structure. It appears as ultrafine powder ranging from brown-black to dark brown, which differs from crystalline boron. It is mainly produced by magnesiothermic reduction followed by multi-stage purification.
Its neutron absorption mechanism depends on the natural isotope ¹⁰B (natural abundance approx. 19.9%). ¹⁰B has an extremely high thermal neutron capture cross-section of 3840 barn. The nuclear reaction ¹⁰B (n,α)⁷Li enables efficient capture of thermal neutrons, making it a classic neutron-absorbing functional phase in the nuclear industry. Compared with boron carbide, amorphous boron features higher activity and better dispersibility in polymer/metal matrices with less agglomeration. It is suitable for formulation development of thin, lightweight and flexible neutron shielding materials.
2. Key Physical & Chemical Specifications (Grades for Neutron-Absorbing Composites)
| Item | Parameter |
|---|---|
| Boron Purity | B95 / B99 / B99.9 (customizable on request) |
| True Density | 2.34～2.37 g/cm³ |
| Mohs Hardness | 9.0～9.3 |
| Particle Size Range | D50: 0.5μm～10μm (submicron and micron grades available) |
| Microscopic Morphology | Irregular amorphous particles, high specific surface area, strong reactivity |
| Impurity Control | Low-impurity grades for Mg, Fe, Si, Al (nuclear grade compatible) |
| Solubility | Insoluble in water, alcohols and ethers; soluble in concentrated nitric acid and concentrated sulfuric acid |
| Stability | Stable in dry air at ambient temperature; prone to oxidation at high temperature in the presence of oxygen |
✅ Core Advantages vs. Crystalline Boron / Boron Carbide: The amorphous structure provides abundant active sites and good powder wettability. It disperses evenly in epoxy resin, UHMWPE and molten aluminum with low settling and agglomeration tendency. It delivers higher boron atom utilization at the same loading rate, ideal for manufacturing thin shielding panels, coatings and flexible shielding felts. ¹⁰B enrichment service is available to further improve neutron absorption efficiency for high-demand working conditions.
3. Product Features
- Excellent neutron absorption performance: Natural boron contains ¹⁰B, offering strong thermal neutron capture capacity, stable shielding performance and low secondary radiation after irradiation.
- Wide matrix compatibility: It can be filled into polyethylene, epoxy, silicone rubber, aluminum, magnesium and other resin/metal matrices to produce various composite shielding materials.
- Good processability: Free of hard agglomerates, suitable for internal mixing, extrusion, calendering, spraying and hot-press sintering processes.
- Lightweight: Much lower density than heavy-metal shielding materials, suitable for vehicle-mounted packages, transport containers and mobile shielding units.
- Flexible grade selection: B95 for general use; B99/B99.9 high-purity nuclear grades with strict impurity control to meet quality assurance requirements of nuclear facilities.
4. Main Application Fields (Neutron Absorption)
- Neutron shielding plates and shielding modules for dry casks and storage pools of spent fuel, boron polyethylene shielding panels
- Reactor control materials, emergency scram components, shielding walls and shielding doors for neutron sources
- Neutron protective coatings and flexible shielding fabrics for radioactive laboratories, flaw detection rooms and nuclear medicine facilities
- Sensitive coatings for neutron detectors, boron-containing metal matrix neutron-absorbing composites (B/Al, B/Cu)
- Lightweight neutron radiation protection components for aerospace and special equipment