Ceramic material properties

Alumina 96 (Aℓ2O396%) properties (physical)
Item Unit  
Bending strength k/cm2 3,000
Mpa 294
Apparent specific gravity 3.7
Water absorption rate 0
Melting point 2,020
Thermal conductivity Cal/cm・secs.℃ 0.04
Thermal expansion coefficient 20-500×10-6/℃ 7.3
500-800×10-6/℃ 8.0
Specific resistance Ωcm >1014
Dielectric strength KV/mm >10  
Specific permittivity(1KHz) 9.0
Dissipation factor(1KHz) tan×10-4 10
Alumina 96 properties (chemical resistance)
Chemical name Temperature Time Evaluation
35%Hydrochloric acid Boiling 30 mins.
70% nitric acid Boiling 30 mins.
98% sulfuric acid Boiling 30 mins.
90% phosphoric acid Boiling 30 mins.
60% hydrofluoric acid 20℃ 24Time
10% potassium hydroxide 80℃ 7 days
Potassium hydroxide 500℃(Boiling) 24 hrs.
Sodium hydroxide 500℃(Boiling) 24 hrs.
Sodium carbonate 900℃(Boiling) 24 hrs.
Sodium sulfate 1000℃(Boiling) 24 hrs.
Potassium fluoride 90℃(Boiling) 4 hrs. ×

◎:No erosion ○:Slight erosion △:Some erosion ×:Major erosion

Steatite properties (physical)
Item Unit  
Code   HB
Color   Black
Apparent density g/cm3 2.8
Water absorption rate 0
Bending strength Mpa 120
Thermal conductivity W/mK 3
Thermal expansion coefficient 20-500℃×10-6/℃ 8.7
20-800℃×10-6/℃ 9.6
Volume resistivity Ω・cm >1014
Dielectric strength kV/mm >10
Ceramic products are co-developed by Hirosugi-Keiki Co., Ltd. and Ohtsuka Ceramics Co., Ltd.