- Temporarily fired alumina is pressure-formed on a briquetting machine, dried, and sintered at high temperature near its melting point (2050°C) in a rotary kiln.
- It is a polycrystalline sintered body of corundum having a dense internal structure. It is high-purity SINTERED ALUMINA containing 99.5% of Al2O3.
- This product has the following advantageous chemical and physical properties:
- High mechanical strength
- High thermal conductivity
- High resistance to thermal shock
- High melting point
- High electric insulation
- High chemical stability
- High resistance to wear
We manufacture 2 types of SINTERED ALUMINA, A-37 and A-S, having respective unique features.
A-37
We developed this SINTERED ALUMINA in 1971 by our original manufacturing method. By adding a slight amount of MgO, it is controlled to suppress abnormal crystalline growth and have the uniform structure of 20 – 40μm.
A-S
This SINTERED ALUMINA is highly stable in volume at high temperature. Special attention is directed so that the invasion of even an infinitesimal quantity of impurities can be prevented.
MgO is not added.
Typical property
| A-37 | A-S | ||||
|---|---|---|---|---|---|
| Coarse/medium grain product | Ball mill crushed product | Coarse/medium grain product | Ball mill crushed product | ||
| Chemical composition (%) | Al2O3 | 99.53 | 99.52 | 99.68 | 99.67 |
| SiO2 | 0.02 | 0.04 | 0.02 | 0.02 | |
| Fe2O3 | 0.02 | 0.03 | 0.02 | 0.03 | |
| TiO2 | Tr. | Tr. | Tr. | Tr. | |
| CaO | 0.12 | 0.12 | 0.03 | 0.03 | |
| MgO | 0.08 | 0.08 | Tr. | Tr. | |
| K2O | 0.01 | 0.01 | Tr. | Tr. | |
| Na2O | 0.22 | 0.20 | 0.25 | 0.25 | |
| Ig.loss | Tr. | Tr. | Tr. | Tr. | |
| Total | 100.00 | 100.00 | 100.00 | 100.00 | |
| Physical property | Apparent specific gravity | 3.82 | - | 3.79 | - |
| Bulk specific gravity | 3.74 | - | 3.61 | - | |
| Water absorption (%) | 0.5 | - | 1.3 | - | |
| Apparent porosity (%) | 1.9 | - | 4.8 | - | |
| True specific gravity | 3.94 | - | 3.94 | - | |
| True porosity (%) | 5.3 | - | 7.6 | - | |
| Coefficient of thermal expansion (×10-6/°C) |
20-800 °C | 8.6 | - | 8.6 | - |
| 20-1500 °C | 8.6 | - | 8.7 | - | |
Specification
| A-37 | A-S | ||||
|---|---|---|---|---|---|
| Coarse/medium grain product | Ball mill crushed product | Coarse/medium grain product | Ball mill crushed product | ||
| Chemical composition (%) | Al2O3 | 99.50 min. | 99.00 min. | 99.50 min. | 99.00 min. |
| SiO2 | 0.10 max. | 0.20 max. | 0.10 max. | 0.20 max. | |
| Fe2O3 | 0.10 max. | 0.15 max. | 0.10 max. | 0.15 max. | |
| CaO + MgO | 0.25 max. | 0.25 max. | 0.10 max. | 0.10 max. | |
| K2O + Na2O | 0.30 max. | 0.30 max. | 0.30 max. | 0.30 max. | |
| Physical property (6-10 mesh crushed product) |
Bulk specific gravity | 3.60 min. | - | 3.55 min. | - |
| Apparent porosity (%) | 5.0 max. | - | 8.0 max. | - | |
Download of Standard Sheet
ALUMINITE (Sintered Alumina) Sieve Specifications (PDF file 397KB)
If you have any inquiry, please contact the following:
[Ceramics Sales Dept.]
1-1, Higashiyamaji-cho.Seto-shi,Aichi 489-0854, Japan
Tel: +81-561-41-9035 Fax:+81-561-21-4166
