Ceramic Insulator Features:
90%, 95%, 99% Al2O3 Alumina Ceramic Insulator Tube.
90%, 95%, 99% Al2O3 Alumina Ceramic Insulator Tube.
Material: 90%-99.8% alumina optional
Mainly Usage:
1. Heat treatment furnace and toughened furnace
2. Inner liner tube and heating tube in electric furnace
Features:
1. Great mechanical strength
2. High softening temperature
3. Good resistance to thermal impact
4. Small thermal expansion coefficient
5. Resistance to acid and alkali corrosion
Application:
Electric appliance industry
Automotive industry
Mechanical industry
Engineer industry
Automotive industry
Mechanical industry
Engineer industry
|
Chemical competent
|
Al2O3
|
≥ 99.5%
|
|
SiO2
|
< 0.2%
|
|
|
Fe2O3
|
< 0.1%
|
|
|
Alkaline matter
|
< 0.1%
|
|
|
Density
|
3.9 g/cm3
|
|
|
Hardness
|
9 M
|
|
|
Water absorption
|
< 0.1%
|
|
|
Ruptures trength
|
> 2000kg/cm2
|
|
|
Gas tightness
|
Kept for ten minutes at negative pressure of 1.3Kpa.
The pressure drop is less than 0.3Kpa.
|
|
|
Thermal tolerance
|
Insert the pipe into the furnace at a depth of 20mm.
Heat to 1600º C and maintain for 30 minutes.
|
|
|
Alkali tolerance
|
In the Na2CO3 solution of 2N concentration, boil for
15 hours with the weight loss not greater than 20mg/dm2.
|
|
|
Volume resistance
|
> 9*10(5) Ω · cm/1600º C
|
|
|
Breakdown voltage
|
20kv/cm
|
|
|
Expansion coefficient
|
8*10(-8)
|
|
|
Temperature for use
|
Long-term: 1600º C Short-term: 1800º C
|
|
|
Chill and abrupt heat
|
1500º C~room temperature not cracking thrice.
|
|
|
Material
|
65 Al2o3
|
75 Al2o3
|
80 Al2o3
|
85 Al2o3
|
90 Al2o3
|
95 Al2o3
|
99 Al2o3
|
|
Al2o3
|
65%
|
75%
|
80%
|
85%
|
90%
|
93%
|
99.3%
|
|
Fe2o3
|
≤ 4
|
≤ 2
|
≤ 1.5
|
≤ 1.0
|
≤ 0.5
|
≤ 0.5
|
≤ 0.3
|
|
Desnsity: g / cm3
|
2.8
|
3.10
|
3.20
|
3.40
|
3.50
|
3.60
|
3.85
|
|
Vickers Hardness
|
7.5
|
≤ 7.8
|
≥ 8
|
≥ 8.6
|
≥ 8.8
|
9
|
9
|
|
Water Absorption: %
|
≤ 4
|
≤ 1
|
≤ 0.5
|
≤ 0.2
|
≤ 0.1
|
≤ 0.085
|
≤ 0.01
|
|
Refractoriness: ° C
|
1300 ° C
|
1400 ° C
|
1450 ° C
|
1580 ° C
|
1600 ° C
|
1650 ° C
|
1800° C
|
|
Flexural Strength: Mpa
|
80
|
100
|
150
|
180
|
200
|
240
|
280
|
|
Wear Rate( at room
temperature, erosion,
100 grinding)%
|
≤ 5
|
≤ 4.5
|
≤ 3.5
|
≤ 3
|
≤ 2.5
|
≤ 1
|
≤ 0.5
|