Brown Fused Alumina (BFA) is a commonly used abrasive for blasting titanium parts due to its hardness, durability, and ability to provide a consistent surface finish. Here’s what you need to know about using BFA for titanium part blasting:
Key Properties of Brown Fused Alumina (BFA) for Titanium Blasting:
Hardness (Mohs 9.0): Effective for removing oxides, scale, and contaminants without embedding excessively.
Angular Shape: Provides good cutting action for surface preparation.
Reusability: Can be recycled multiple times in blasting operations, making it cost-effective.
Low Iron Content: Reduces the risk of contamination, which is crucial for titanium to prevent corrosion or hydrogen embrittlement.
Applications for Titanium Parts:
Pre-Weld Cleaning: Removes oxides and ensures a clean surface for welding.
Post-Weld Finishing: Cleans weld splatter and heat-affected zones.
Surface Preparation for Coatings: Creates an anchor profile for better adhesion of paints or coatings.
Deburring & Edge Blending: Smooths rough edges after machining.
Recommended Blasting Parameters:
Grit Size: Typically #16 to #80 (coarser for heavy scale removal, finer for smoother finishes).
Pressure: 40-80 PSI (adjust based on part thickness and desired aggressiveness).
Nozzle Distance: 6-12 inches (to avoid excessive embedment).
Media Recycling: Use a closed-loop system to extend abrasive life.
Advantages Over Other Abrasives:
Vs. Silicon Carbide: BFA is less brittle and more cost-effective, though SiC cuts faster.
Vs. Glass Beads: BFA provides a more aggressive cut, while glass beads give a smoother, peened finish.
Vs. Aluminum Oxide: Similar performance, but BFA is often cheaper and more durable.
Safety & Environmental Considerations:
Dust Control: Use proper ventilation or wet blasting to avoid inhalation hazards (silica-free, but dust can still be harmful).
Contamination Risk: Ensure the blasting media is clean (no iron or sulfur residues) to prevent titanium degradation.
Disposal: Spent BFA is non-toxic but should be disposed of properly to avoid environmental accumulation.
Alternative Abrasives for Titanium:
White Fused Alumina (WFA): Higher purity (99% Al₂O₃), used for critical aerospace applications.
Crushed Glass Grit: For lighter cleaning without embedding.