The thermal expansion coefficient of silicon brick varies with the specific type and service temperature range. The following is the coefficient of thermal expansion data for several common situations:

I. Ordinary silicon brick

In the temperature range of 20-1000℃, the thermal expansion coefficient of ordinary silicon brick is about 1.25× 10/℃.

When heated to about 1450℃, the volume expansion rate of ordinary silicon brick is about 1.5%-2.2%.

II. Lightweight silica brick

The thermal expansion coefficient of lightweight silicon brick is low, usually ≤1.3%.

III. Zero expansion silica brick (fused quartz brick)

The main mineral phase of zero expansion silica brick is amorphous silica, and its thermal expansion coefficient is extremely low, only 0.55× 10/℃, which is almost zero.

IV. Characteristics of thermal expansion coefficient of silicon brick

Significant expansion at high temperature: ordinary silicon bricks will have large volume expansion at high temperature (such as 1450℃), and this expansion characteristic needs special attention in practical application, for example, expansion joints should be reserved when building.

Effect of phase transformation: The crystalline phase transformation (such as square Shi Ying phase transformation) will occur between 180-270℃, resulting in a significant increase in volume expansion.

Advantages of low expansion silicon brick: Zero expansion silicon brick is especially suitable for occasions requiring high thermal stability and thermal shock resistance because of its extremely low thermal expansion coefficient.

To sum up, the thermal expansion coefficient of silicon brick varies with the type and service conditions. Ordinary silicon brick has a higher thermal expansion coefficient, while zero expansion silicon brick has a very low thermal expansion coefficient.