We often find that the expansion coefficient of silicon bricks is quite large during the production process, which leaves many people puzzled. Why is that? Next, we will delve into the reasons behind the high expansion coefficient of silicon bricks.

Silica bricks feature high load softening temperature, but low thermal shock stability and lower refractoriness than general high-alumina bricks. At a usage temperature of 1450°C, they exhibit a volume expansion rate of 1.5~2.2%. Even during production, molds must be scaled appropriately according to the expansion coefficient to accommodate expansion and ensure precise dimensions for the bricks.

During the production of silicon bricks, the transformation between quartz, tridymite, and cristobalite in the raw materials disrupts the original crystal structure, leading to a reorganization and formation of new structures. Due to their high activation and transformation temperatures during the firing process, which occur slowly, a significant volume expansion effect is produced.

Sintered silicon brick green bodies form little solution at the firing temperature, making the firing process difficult. A series of physical and chemical changes occur during the firing of silicon brick, causing it to expand by approximately 3 meters in size.