Al₂O₃  %

≥48%

Fe₂O₃ %

≤2.0

Bulk Density g/cm³   ≤

1.0

0.9

0.8

0.7

0.6

0.5

0.4

Cold Crushing Strength Mpa

≥3.92

≥3.43

≥2.94

≥2.45

≥1.96

≥1.47

≥0.78

Thermal Conductivity
(350±25℃)  W/m.k

≤0.5

≤0.45

≤0.35

≤0.35

≤0.30

≤0.25

≤0.20

The Temperature of linear change within 2% on reheating

1400℃

1400℃

1400℃

1350℃

1350℃

1250℃

1250℃

Brand

Density
g/cm³

Pressure Strength
MPa

Tensile Strength
MPa

Shrinkage after Heavy
Firing %

Thermal shock
resistance

Modulus of Thermal
Expansion w/m.k

Al₂O₃
%

Fe₂O₃
%

GD-23

0.6

1.6

1

1250℃×24h
-0.5

20

400℃ 0.15
1000℃ 0.2

40

1.0

GD-26

0.8

2.8

1.4

1450℃×24h
-0.5

20

600℃ 0.25
800℃ 0.27

55

1.0

GD-28

0.85

3.2

1.7

1510℃×24h
-0.5

20

600℃ 0.314
1000℃ 0.347

66

0.9

GD-30

1.0

3.5

2.1

1620℃×24h
-0.6

25

1000℃ 0.45

72

0.7

GD-32

1.2

4.5

2.5

1730℃×24h
-0.6

25

1000℃ 0.56

77

0.6