White fused alumina / corundum / electro‑fused alumina powder (main constituent: α‑Al₂O₃) features high purity, high hardness, good self‑sharpening performance and excellent chemical stability. Owing to its high matching with alumina ceramic substrates in crystal form and thermal expansion coefficient, together with ultra‑low impurity content, it serves as the core precision grinding and polishing media for processing alumina ceramic substrates.
In the processing of alumina ceramic substrates, white fused alumina powder is mainly applied for precision grinding and final polishing after sintering. To achieve superior flatness and eliminate subsurface micro‑cracks, suspensions of white fused alumina powder with different particle sizes are generally used progressively from coarse to fine.
| Main Chemical Composition (%) | ||
|---|---|---|
| Al₂O₃ | Fe₂O₃ | Na₂O |
| 99.2‑99.7 | 0.03‑0.10 | 0.23‑0.32 |
Physical and Chemical Properties of White Fused Alumina
| Item | Value |
|---|---|
| Mohs Hardness | 9.0 |
| Bulk Density | 1.75‑1.95 g/cm³ |
| True Density | 3.95 g/cm³ |
| Bulk Specific Gravity | 3.60 |
| Melting Point | 2250 ℃ |
| Maximum Service Temperature | 1900 ℃ |
Common Grades of White Fused Alumina / Corundum / Electro‑fused Alumina Powder for Alumina Ceramic Substrate Polishing
FEPA European Standard: F230, F240, F280, F320, F360, F400, F500, F600, F800, F1000, F1200, F1500, F2000
JIS Japanese Standard: #240, #280, #320, #360, #400, #500, #600, #700, #800, #1000, #1200, #1500, #2000, #2500, #3000, #4000, #6000, #8000, #10000
