In high-temperature environments such as industrial kilns, metallurgical smelting, and building materials production, refractory bricks are indispensable core materials. Their high-temperature resistance directly determines the operational safety and service life of equipment.
Many users ask when purchasing refractory bricks: How high a temperature can they withstand? There is no single standard answer; the temperature resistance varies significantly depending on the material and formula of the refractory bricks.
The Core Range of High-Temperature Resistance for Refractory Bricks
The high-temperature resistance of refractory bricks is primarily measured by “refractory strength,” which refers to the highest temperature at which it does not soften or melt.
Ordinary refractory bricks: Refractory strength is mostly between 1580℃ and 1770℃, commonly used in medium- and low-temperature environments such as small and medium-sized kilns and flues.
High-grade refractory bricks: Refractory strength can reach 1770℃-2000℃, suitable for medium- and high-temperature industrial environments such as steel and non-ferrous metal smelting.
Premium Refractory Bricks: With a refractoriness exceeding 2000℃, these are primarily used in extreme high-temperature environments such as aerospace and special ceramic firing.
It’s important to note that the actual service temperature of refractory bricks is lower than their refractoriness, typically 80%-90%. This is because factors such as thermal shock and erosion at high temperatures affect their stability.
Temperature Resistance and Applicable Scenarios of Refractory Bricks of Different Materials
1. Clay Refractory Bricks: A Cost-Effective Choice
Manufacturers produce clay refractory bricks primarily using clay as the main raw material.These bricks have a refractoriness ranging from 1580℃ to 1750℃ and stand as the most widely used common refractory bricks.
They are affordable, technologically mature, and capable of withstanding moderate temperature loads. Thus, they fit applications like boilers, glass kiln flues, and brick kilns—where high-temperature resistance needs are not extreme.
2.High-Alumina Refractory Bricks: Mainstay for Medium and High Temperatures
High-alumina refractory bricks have an alumina content ≥48%, a refractoriness of 1750℃-1900℃, and superior high-temperature strength and corrosion resistance compared to clay bricks.
These refractory bricks are widely used in key components of medium- and high-temperature equipment. Examples include blast furnaces, steel plant hot blast stoves, and cement plant rotary kilns.
3.Siliceous Refractory Bricks: Special Bricks for High Temperatures
Siliceous refractory bricks are made from quartz sand, with a refractoriness of 1690℃-1750℃. However, they exhibit slight softening above 1450℃ while maintaining good structural strength.
They are particularly suitable for environments where temperatures are consistently above 1400℃, such as melting pools in glass kilns and carbonization chambers in coke ovens, and exhibit outstanding resistance to acid corrosion.
4.Corundum Refractory Bricks: King of Extreme High Temperatures
Corundum refractory bricks have an alumina content ≥90%, a refractoriness exceeding 2000℃, and are among the varieties with the best high-temperature performance.
High-performance refractory bricks are indispensable for protecting equipment. They are suitable for extreme environments like high-temperature testing furnaces and special metal smelting furnaces in the aerospace industry.
Besides the material, the manufacturing process also affects the high-temperature resistance of refractory bricks. Higher raw material purity and higher sintering temperature result in better density of the refractory bricks, leading to stronger high-temperature resistance and corrosion resistance.
The operating environment is equally important. High-temperature acid and alkali media and frequent thermal shock will accelerate the aging of refractory bricks, reducing their actual operating temperature and service life.
Selection Recommendations and Cooperation Invitation
When choosing refractory bricks, don’t rely solely on refractoriness. You should make a thorough assessment according to the actual operating temperature, media environment, and equipment requirements.
If you are selecting suitable refractory bricks for high-temperature applications or would like to learn about the specific material’s operating temperature and selection options. Please contact us!
We have a professional technical team that can provide customized refractory brick products and comprehensive technical support based on your specific needs. That ensuring safer and longer-lasting operation of high-temperature equipment. We look forward to working with you to create a stable and efficient production environment!