What Is Fused Silica B Grade?

Fused Silica B Grade is an electrically fused amorphous silica material produced from high-purity silica and rapidly cooled to prevent crystallization.

With SiO₂ ≥ 99.8%, it offers an excellent balance between high purity, stable particle size distribution, and cost efficiency, making it one of the most widely used grades in investment casting and refractory industries.

Fused Silica B Grade is ideal where performance stability and economic efficiency are both required.

Product Images

Fused Silica B Grade high purity material
Fused Silica B Grade – High Purity Material
Fused Silica B Grade 0-0.2mm powder
0–0.2 mm Fine Powder
Fused Silica B Grade 20-50 mesh
20–50 Mesh Medium Grade
Fused Silica B Grade 200 mesh powder
200 Mesh Ultra-Fine Powder
Fused Silica B Grade grains
Coarse Grains for Foundry

Key Features & Advantages of Fused Silica B Grade

  • High Purity: SiO₂ ≥ 99.8% (grains)
  • Extremely Low Thermal Expansion: 5 × 10⁻⁷ /°C (20–700°C)
  • Excellent Thermal Shock Resistance
  • High Refractoriness & Thermal Stability
  • Stable PSD for Casting & Foundry Use
  • Cost-Effective Alternative to A Grade

Chemical & Physical Properties

Chemical Composition (Typical Values)

Component Specification
SiO₂ (Grains) 99.8% min
SiO₂ (Powders) 99.7% min
Al₂O₃ ≤ 500 ppm
Fe₂O₃ ≤ 300 ppm
Na₂O ≤ 100 ppm
K₂O ≤ 100 ppm
Magnetic Impurities ≤ 100 ppm

Physical Properties

Property Value
Bulk Density 2.18 – 2.20 g/cm³
pH Value ~6
Melting Temperature 1750°C
Softening Temperature 1650°C
Thermal Expansion (20–700°C) 5 × 10⁻⁷ /°C

Particle Size Distribution & Available Grades

Standard ISO Sizes

0–1 mm 1–3 mm 3–5 mm 3–6 mm 0.1–0.2 mm 0.2–0.5 mm 0.5–1 mm

ASTM Sizes

4×10 Mesh 10×20 Mesh 20×50 Mesh 50×100 Mesh 120F 140F 200F 325F

Typical PSD for Investment Casting

Sieve Size Percentage
+2.0 mm 2–8%
+1.0 mm 40–60%
+0.5 mm 30–50%
+0.212 mm 2–8%

120F Powder Distribution

Sieve Size Percentage
+0.063 mm 15–30%
−0.063 mm 60–80%

Custom PSD can be supplied according to customer requirements.

Mineralogical Structure

Phase Content
Amorphous Glass > 99%
Cristobalite / Crystalline Phase < 1%

Typical Applications of Fused Silica B Grade

Fused Silica B Grade is widely used in applications requiring low thermal expansion, thermal shock resistance, and chemical stability:

Investment casting sand and flour
Fused silica crucibles for silicon ingot
Fused silica nozzles for steel industry
Furnace lining & ramming mass
Fused silica rollers for ceramic kilns
Monolithic castables for metal runners
Zero-expansion fused silica bricks
Electronic sealing materials (epoxy fillers)
SLSI packaging materials
Anti-acid applications in petrochemical

Packaging & Supply Options

  • 1000 kg / 1250 kg Super Sacks
  • 25 kg bags in big bags
  • 25 kg bags on pallets

Export-standard packaging ensures safe transportation and consistent quality.