1. Introduction

Brown Fused Alumina (BFA) is a widely used abrasive in sandblasting thanks to its high hardness, strong cutting ability, and excellent recyclability. For industries requiring aggressive material removal—such as steel surface cleaning, rust removal, and surface roughening—BFA offers a cost-effective and high-performance solution.
Choosing the correct grit size is essential because particle size directly affects surface profile, blasting efficiency, and media consumption.

This guide explains how to select BFA grit sizes from #12 to #60 for different sandblasting applications.

2. Key Properties of Brown Fused Alumina for Sandblasting

BFA is characterized by:

• Mohs hardness: 9.0

• High toughness (more resistant to fracturing than white alumina)

• Blocky, angular particles that produce strong cutting action

• Recyclability (typically 4–10 cycles depending on application)

• Stable performance for dry and wet blasting

These properties make BFA ideal for aggressive blasting where deep profiles or heavy rust removal are required.

3. How Grit Size Affects Blasting Performance

The grit size determines blasting results:

• Coarse grits (#12–#20) → deep surface profile, rapid material removal

• Medium grits (#24–#36) → balanced cleaning + profiling

• Fine grits (#46–#60) → smoother finish, surface preparation before coating

In general:
The smaller the grit number, the larger the particle, the stronger the cutting force.

4. Grit Size Selection Guide (#12–#60)

#12 – Very Coarse

Use for:

• Heavy rust removal

• Thick coating stripping

• Deep anchor profile on steel plates

Surface profile: 80–120 μm
Very aggressive impact, suitable for large steel structures.

#16 – Coarse

Use for:

• Removing old paint layers

• Heavy weld cleaning

• Ship hull maintenance

Surface profile: 70–110 μm
Ideal for industries requiring strong cutting power.

#20 – Coarse/Medium

Use for:

• Cleaning of cast iron parts

• Mill scale removal

• Pre-coating surface roughening

Surface profile: 60–100 μm
Balanced cutting efficiency and abrasive consumption.

#24 – Medium

Use for:

• Steel structure blasting

• Pipeline surface preparation (medium profile)

• General industrial cleaning

Surface profile: 50–80 μm
Most commonly used for industrial blasting lines.

#30 – Medium/Fine

Use for:

• Aluminum surface cleaning

• Machinery parts preparation

• Removing moderate corrosion

Surface profile: 40–70 μm
Produces a moderately smooth finish.

#36 – Fine

Use for:

• Precision component cleaning

• Aerospace and automotive parts

• Achieving moderate coating adhesion

Surface profile: 30–55 μm
Lower aggressiveness, more uniform finish.

#46 – Fine

Use for:

• Light cleaning without damaging the substrate

• Stainless steel blasting

• Satin or matte finish

Surface profile: 20–40 μm
Ideal for non-ferrous materials.

#60 – Very Fine

Use for:

• Final surface refinement before coating

• Decorative finish on aluminum or stainless steel

• Light oxide removal

Surface profile: 15–30 μm
Produces a smooth, uniform appearance.

5. Tips for Best Sandblasting Results

To maximize performance with BFA:

• Ensure dry and clean compressed air

• Maintain consistent nozzle distance (15–30 cm)

• Adjust pressure based on grit size (0.4–0.7 MPa)

• Use proper recycling systems to reduce dust and media loss

• Replace fine particles regularly to maintain cutting efficiency

6. Conclusion

Brown fused alumina is a dependable abrasive for sandblasting due to its hardness, toughness, and aggressive cutting ability. By choosing the right grit size—from coarse #12 to fine #60—users can achieve the desired balance between cleaning power, surface profile, and finish quality.
Correct grit selection ensures better coating adhesion, higher efficiency, and a more stable blasting process.