The type of bricks that can withstand high temperatures as a building material is refractory bricks or fire bricks. Generally, the color of fire bricks is white and yellowish-white, weighing around 3 kg each. They have to have a high point for fusion.
Fire clay is used to make bricks of this kind. This clay could survive high temperatures without significant changes to structural properties such as melting or softening.
Properties of Good Refractory Bricks
The refractory bricks must be healthy in quality in order to serve the desired purpose. The following are good refractory bricks ‘ properties.
- Refractory bricks must withstand pressure produced in furnace walls and arches at high temperatures.
- Their rigidity must be preserved at high temperatures.
- The irreversible change in volume at the furnace temperature should not occur.
- Since shrinking contributes to the joint opening which leads to a leaky furnace.
- When exposed to a sudden change in temperature, they must resist the tendency to crack and split fragments.
- They are not easily allowed to form fusible slag products.
- They can not react with gases from the furnace.
- The weight of refractory bricks should be roughly 150 lbs per cubic ft.
- They should take between 20000 and 30000 psi of compressive strength.
- Once held in liquid for 24 hours, they should not consume more than 6% of water per wt.