News detail
High Alumina Brick: Premium Refractory Brick for High-Temperature Kilns & Furnaces
Introduction
High alumina brick is a widely used shaped refractory material with alumina (Al₂O₃) content ≥48%. Manufactured from calcined bauxite and high-purity alumina aggregates, fired at ultra-high temperature in tunnel kilns, it delivers outstanding thermal stability, mechanical strength and slag resistance. Compared with traditional fireclay bricks, high alumina bricks perform far better under extreme heat, heavy load and slag erosion. It serves as the core lining material for high-temperature industrial furnaces across global metallurgy, cement, power and chemical industries.
What is High Alumina Brick?
High alumina brick belongs to the alumina-silicate refractory family. Its core raw material is sintered bauxite clinker, mixed with bonding clay and functional additives. After raw material crushing, proportioning, pressing and high-temperature sintering, the finished brick forms stable mullite and corundum crystal phases.
The alumina percentage directly decides its refractory performance. Higher Al₂O₃ content brings higher refractoriness, better load softening performance and stronger slag resistance. Common grades include 48%, 55%, 60%, 65%, 75%, 80% and above. When alumina exceeds 90%, it is classified as corundum brick for ultra-severe working conditions.
Key Physical & Chemical Properties
High Refractoriness
Refractoriness normally reaches 1750–1850°C. High-grade corundum-type high alumina bricks can resist temperature up to 1900–2000°C without softening or melting. It keeps stable structure under continuous high-temperature operation.
Excellent Refractoriness Under Load
High alumina brick maintains dimensional stability under combined high temperature and mechanical load. Its load softening temperature ranges from 1400°C to 1600°C, avoiding deformation and collapse in furnace hot zones.
Good Slag & Corrosion Resistance
Alumina is amphoteric, so the brick resists both acid slag and alkaline slag erosion. It effectively blocks penetration of molten slag, metal liquid and alkali vapor, greatly reducing lining damage in metallurgical and cement kilns.
High Mechanical Strength & Wear Resistance
High bulk density and low apparent porosity bring high cold crushing strength. It can bear mechanical friction, impact and pressure inside rotary kilns and blast furnaces, showing good wear resistance in long-cycle continuous production.
Thermal Shock Stability
Properly formulated high alumina bricks can withstand repeated rapid heating and cooling cycles. It avoids cracking and peeling caused by frequent furnace startup and shutdown, lowering maintenance frequency.
Main Grades & Classification
High alumina bricks are mainly categorized by alumina content, which is the standard adopted by GB/T 2988 and ASTM C27.
- LZ-48: Al₂O₃ ≥48%, suitable for medium-temperature kilns with mild slag attack
- LZ-55 / LZ-60: 55~60% Al₂O₃, widely used for cement preheaters and boiler linings
- LZ-65 / LZ-70: 65~70% Al₂O₃, applied in blast furnace stacks and hot blast stoves
- LZ-75 / LZ-80: 75~80% Al₂O₃, for severe slag zones in steel and non-ferrous smelting furnaces
Custom special-shape high alumina bricks are also available for complex furnace structures, including arch bricks, wedge bricks and anchor bricks.
Industrial Applications
Iron & Steel Metallurgy
Blast furnace linings, hot blast stoves, electric arc furnace roofs, soaking pits, tundish lining and regenerator checker bricks. It handles heavy load and slag erosion in ironmaking and steelmaking processes.
Cement Industry
Rotary kiln transition zones, preheater, cooler and calciner linings. It resists alkali corrosion and thermal cycling inside cement kilns and extends kiln campaign life.
Non-Ferrous Metallurgy
Smelting furnaces for aluminum, copper, lead and zinc. It works well in molten metal and corrosive flue gas environments.
Power & Chemical Industry
Boiler linings, waste incinerators, petroleum cracking furnaces and hydrogen reformers. It provides reliable lining protection for high-temperature chemical reactors.
Ceramic & Glass Industry
Kiln car linings, tunnel kiln walls and glass furnace auxiliary structures.
Advantages of Our High Alumina Bricks
- Stable batch quality, strict raw material inspection and full testing report before shipment.
- Complete grade options, standard bricks and custom special shapes available.
- Low creep rate and long service life to reduce furnace downtime and replacement cost.
- Support bulk export, mixed container loading and technical support for furnace lining design.
- Full COA certificate, ISO certified production, suitable for global market export.
How to Select Suitable High Alumina Brick
When choosing grades, evaluate three core factors: maximum operating temperature, slag or alkali exposure level, and thermal shock frequency.
- Medium temperature, light corrosion: choose 48~60% Al₂O₃ grade for cost control.
- High temperature with heavy slag erosion: select 65~80% high alumina bricks.
- Frequent start-stop and sharp temperature changes: pick high thermal shock resistant formulations.
Over-specification will raise unnecessary material cost, while under-specification causes early lining failure. Our technical team can recommend the best grade according to your furnace working conditions.
Packing & Delivery
Standard high alumina bricks are packed in wooden pallets with waterproof plastic wrapping. We can arrange FOB, CIF, DAP and other international trade terms. Bulk shipment can be loaded in 20GP or 40HQ containers. We support pre-shipment inspection and provide full set of export documents including packing list, commercial invoice and COA.
Contact Us for Inquiry
If you need high alumina bricks for your kiln or furnace project, send us your working temperature, slag condition, brick size and required quantity. Our refractory engineers will provide professional product recommendation and competitive quotation.
Send inquiry
Please Leave your message you want to know! We will respond to your inquiry within 24 hours!