Can alumina be used as refractory material?

Alumina can be used as a refractory material. Its high melting point (above 2050°C) and chemical stability enable it to be widely applied in high-temperature industries. The application characteristics of alumina as a refractory material are as follows:

1. High-temperature stability:

Alumina (Al₂O₃) has a melting point as high as 2054°C and can still maintain structural stability at high temperatures, which is a core characteristic for manufacturing refractory materials.‌‌1‌‌2 The α-Al₂O₃ crystal form (trigonal crystal system) is the most stable among all alumina forms, and it is especially suitable for high-temperature environments, often used in the corundum phase structure of refractory materials.‌‌

2. Main application forms:

Alumina-based insulating refractory bricks: Made from fused corundum and sintered alumina, they can be used for a long time below 1700°C, with strong thermal shock resistance and chemical corrosion resistance.‌‌

Foamed alumina bricks: With an alumina content of over 90%, they are lightweight and high-temperature resistant, suitable for energy-saving industrial kilns.‌‌6 Unshaped refractory materials: Such as refractory castables and plastic refractories, α-alumina powder can improve the high-temperature strength and erosion resistance of the materials.‌‌

3. Performance advantages:

Chemical inertness: Resistant to acid and alkali erosion and reducing atmospheres.‌‌

Mechanical properties: High hardness and wear resistance, suitable for the linings of high-temperature equipment in metallurgy, ceramics and other industries.‌‌