Brown Fused Alumina (BFA) for Whetstone
1. Basic Introduction
Brown fused alumina (BFA) is a synthetic abrasive smelted from bauxite in an electric arc furnace at high temperature. It is the most widely used raw material for whetstones, sharpening stones and oil stones.
| SPLIT SIZE | AL2O3 MIN | SIO2 MAX | TIO2 MAX | Fe2O3 MAX |
| 12#-80# | 94.5-97% | 0.6-0.8% | 1.5-3% | 0.12-0.2% |
| 100#-180# | 94-955% | 0.7-1% | 1.5-3.8% | 0.15-0.25% |
| 240#-280# | 94-95% | 0.85-1.1% | 1.5-3.8% | 0.18-0.35% |
2. Chemical & Physical Properties
- Main composition: Al₂O₃ 94%–97%
- Color: Brown / reddish brown
- Mohs hardness: 9.0
- Melting point: ≈2050℃
- Features: High hardness, excellent toughness, good self-sharpening, high wear resistance, low cost
3. Advantages for Whetstone Making
- Strong cutting ability, fast metal removal
- High toughness, not easy to chip or drop grains
- Good self-sharpening performance; new sharp edges keep exposing during sharpening
- Less heat generation, no easy to burn the knife edge
- Stable slurry forming when using water, smooth sharpening feel
- Cost-effective, ideal for daily household and general tool sharpening
4. Grit Size Common for Whetstone
Coarse grit: 240# / 400# — Fix chipped edges, new blade edge setting
Medium grit: 600# / 1000# — Daily quick sharpening
Fine grit: 1500# / 3000# — Fine finishing and polishing
Medium grit: 600# / 1000# — Daily quick sharpening
Fine grit: 1500# / 3000# — Fine finishing and polishing
5. Application
Used for manufacturing double-sided whetstone, bench stone, oil stone, grinding stone for kitchen knives, scissors, axes, farm tools and general carbon steel / stainless steel tools.