Specifications

Main chemical compositon %

Magnetic material content %

Al₂O₃

Fe₂O₃

SiO₂

Na₂O

Section sand ( I)

≥98.3

≤0.15

≤1.00

≤0.10

≤0.05

Fine sand ( I)

≥97.8

≤0.30

≤0.10

Setion sand (II)

≥99.0

≤0.10

≤1.00

≤0.10

≤0.05

Fine sand (II)

≥98.6

≤0.10

≤0.05

Item

Index

Color

Gray

Crystalline system

Hexagon

Hardness (Mohs scale)

≥9.0

Melting point ( ℃)

2250

Maximum operated temperature (℃)

1900

Real density (g/cm³)

≥3.90

Linear expansion coefficient (1600℃)

7-9