Advanced Search
enLanguage

Products

Home/Products / Other Related Products/Details
Silica Fume

Silica Fume

Silicon metal powder is a kind of powdered silicon metal, which has the same composition as lump silicon metal.The appearance of silicon metal powder is silver gray or dark gray powder with metallic luster.The size of silicon metal powder is usually between 10-100 microns. During the processing, due to different production processes and requirements, metal silicon powder of different particle sizes may be produced. Generally speaking, the larger the mesh number, the finer the material size; the smaller the mesh number, the larger the material size.
-------------------------------------------------------------------------------------------
Shape: Powder
-------------------------------------------------------------------------------------------
Chemical Composition:Si Fe Al Ca P
-------------------------------------------------------------------------------------------
Size:1-3mm 3-5mm 30-325mesh .etc
-------------------------------------------------------------------------------------------
Package: Ton bag or customized according to customer requirements
Send Inquiry
Product Introduction

Silica Fume (also known as micro silica powder or condensed silica fume) is a ultra-fine, amorphous silica powder produced as a byproduct of ferrosilicon or silicon metal smelting. It is defined by its extreme fineness (average size 0.1–0.3μm, 50–100x finer than cement), high silica content (SiO₂≥85%), and high pozzolanic activity (reacts with calcium hydroxide in concrete to form strength-enhancing compounds). Unlike traditional pozzolans (e.g., fly ash, slag), Silica Fume delivers unmatched improvements in concrete strength, durability, and impermeability-making it indispensable for high-performance applications like high-strength concrete (HSC), precast components, and refractory castables.

 

Silica Fume is a byproduct of the submerged arc furnace smelting process for ferrosilicon (FeSi) or silicon metal. When quartz and coke are heated to 1800–2000℃, volatile silica (SiO) gas is released, which condenses in the furnace's exhaust system to form ultra-fine amorphous silica particles. Its core value lies in solving three critical material pain points:


 Low Concrete Strength: Enhances compressive strength of concrete by 30–50% (vs. plain concrete), enabling the production of HSC (≥60 MPa) for skyscrapers and bridges.
 Poor Durability: Reduces concrete permeability by 80–90%, resisting chloride ion penetration (critical for marine or de-icing salt environments) and sulfate attack.
 Refractory Weakness: Improves high-temperature strength and thermal shock resistance of refractory castables, extending furnace service life by 2–3x.


These traits make Silica Fume a "performance booster" for materials requiring extreme strength, durability, or heat resistance.

 

silica fume

chemical composition

Parameter Industrial Grade (IG) Premium Grade (PG) High-Purity Grade (HPG) Industrial Significance
Chemical Composition SiO₂: 85–90% SiO₂: 90–95% SiO₂: ≥95% Higher SiO₂ content increases pozzolanic activity-critical for high-strength concrete.
Free C: ≤3.0%, Moisture: ≤3.0% Free C: ≤1.5%, Moisture: ≤2.0% Free C: ≤0.5%, Moisture: ≤1.0% Free C ≤1.0% avoids concrete discoloration; low moisture preserves reactivity.
Fe₂O₃: ≤1.5%, Al₂O₃: ≤2.0% Fe₂O₃: ≤1.0%, Al₂O₃: ≤1.5% Fe₂O₃: ≤0.5%, Al₂O₃: ≤1.0% Low metal oxides prevent concrete efflorescence and improve refractory thermal stability.
Physical Properties Average Particle Size: 0.1–0.3μm Same as left Same as left Ultra-fine particles fill concrete voids (micro-filling effect) and accelerate hydration.
Specific Surface Area (SSA): 15–25 m²/g 20–30 m²/g 25–35 m²/g Larger SSA (HPG grade) enhances reactivity-ideal for fast-curing precast concrete.
Bulk Density (Powder): 0.15–0.25 g/cm³ Same as left Same as left Low bulk density requires agglomeration for easy handling; agglomerated density: 0.6–0.8 g/cm³.
Pozzolanic Activity Index ≥85% (7 days) ≥90% (7 days) ≥95% (7 days) Higher activity index means faster strength development-HPG grade reaches 100% at 28 days.

Key Benefits vs. Traditional Pozzolans (Fly Ash, Slag)

Benefit Impact on Materials Data Support (vs. Fly Ash)
Faster Strength Development Accelerates concrete early strength (7 days) and boosts 28-day strength by 30–50%. High-strength concrete with Silica Fume reaches 60 MPa at 7 days (vs. 40 MPa with fly ash).
Superior Impermeability Reduces concrete porosity by 80–90%, blocking chloride/sulfate penetration. Chloride ion penetration depth: 2mm (Silica Fume concrete) vs. 15mm (fly ash concrete) in marine environments.
Better Refractory Performance Improves refractory castable hot modulus of rupture (HMOR) at 1400℃ by 40–60%. Refractories with Silica Fume have HMOR 8 MPa (vs. 5 MPa with slag) at 1400℃.
Reduced Shrinkage Minimizes concrete drying shrinkage by 20–30% (micro-filling effect reduces voids). Drying shrinkage: 0.03% (Silica Fume concrete) vs. 0.045% (plain concrete) at 28 days.

Application areas

 

Building materials:

Microsilica powder is widely used in cement, concrete and mortar. As an admixture, it can improve the strength, durability and corrosion resistance of materials.

Chemical industry:

Used as a filler for silicone rubber and silicone resin to improve the physical properties and weather resistance of products.

Electronic materials:

Used in the semiconductor industry to manufacture transistors, integrated circuits, etc.

Metal smelting:

As a reducing agent and alloy additive, it plays an important role in the metallurgical industry.

 

Contact us today to request a customized quote and technical datasheet – elevate your material performance with high-quality Silica Fume!

 

microsilica

 

 

 

Hot Tags: silica fume, China silica fume manufacturers, suppliers, factory, Ferro Silicon 75, Silicon Manganese Briquette, High Carbon Ferro Silicon, Ferro Silicon Powder, Silicon Manganese 6014, Ferrochrome Alloy

You Might Also Like

(0/10)

clearall