Micro Silica Powder Factory Price
Micro Silica Powder Factory Price
Micro silica, also known as silica fume, is a by‑product of silicon metal and ferrosilicon alloy production. Its primary value lies in the ultra‑fine particle size (average 0.1 µm) and high specific surface area, which enable pozzolanic reactions in cementitious systems.
Technical Characteristics
The powder consists of amorphous SiO₂ with a typical loss on ignition (LOI) below 3 %. Particle size distribution shows D50 around 0.12 µm and D99 under 1 µm. Bulk density ranges from 200 to 300 kg/m³ depending on compaction.
- SiO₂ content: ≥ 85 % (often 90‑98 %)
- Specific surface area (BET): 15‑30 m²/g
- pH of slurry (10 % w/w): 4‑6
- Moisture content: ≤ 1 %
Primary Applications
In concrete technology, micro silica improves compressive strength by filling capillary pores and promoting calcium silicate hydrate (C‑S‑H) formation. The pozzolanic reaction consumes calcium hydroxide, reducing permeability and increasing resistance to chloride ingress.
Refractory manufacturers use the powder to enhance sintering behavior and increase hot‑load strength of alumina‑based bricks. In polymer composites, the high surface area acts as a nucleating agent, improving mechanical properties and thermal stability.
Quality Control & Testing
Each batch undergoes laser diffraction for particle size distribution, X‑ray fluorescence for chemical composition, and BET analysis for surface area. Moisture content is determined by thermogravimetric analysis at 105 °C.
- Particle size: D50 0.10‑0.15 µm (ISO 13320)
- Chemical purity: SiO₂ ≥ 90 % (XRF)
- Loss on ignition: ≤ 3 % (ASTM C1240)
- Bulk density: measured per ASTM C29
Factory Price Considerations
The ex‑works price of micro silica powder is influenced by raw material source (silicon metal vs. ferrosilicon), processing route (dry collection vs. wet slurry), and required surface treatment (e.g., silanization for polymer compatibility). Transportation costs vary with bulk density and packaging format.
Typical price ranges (FOB factory) for untreated powder are:
| Specification | Price Range (USD/ton) |
|---|---|
| Standard grade, SiO₂ 92 %, D50 0.12 µm | 350‑420 |
| High purity, SiO₂ ≥ 98 %, low LOI | 480‑560 |
| Surface‑treated (silane) for composites | 620‑720 |
These figures are indicative; final quotations depend on order volume, packaging (25 kg bags, 500 kg FIBC, or bulk tanker), and agreed inspection terms.
Q: Can the particle size be customized?
A: Yes. By adjusting collection temperature and agglomeration conditions, suppliers can shift D50 between 0.08 µm and 0.20 µm to meet specific rheology or reactivity requirements.
Q: What information is needed for a quotation?
A: Required details include desired SiO₂ purity, target particle size distribution, any surface treatment, order quantity, preferred packaging, and delivery incoterm.
Q: How is quality verified before shipment?
A: Suppliers typically provide a certificate of analysis (CoA) covering chemical composition, LOI, BET surface area, and particle size. Third‑party inspection can be arranged upon request.
For a detailed technical datasheet or to discuss project‑specific requirements, please contact our sales team.