Mullite Brick

• Excellent high-temperature stability

• Low thermal expansion and good thermal shock resistance

• Good creep resistance at elevated temperatures

• High refractoriness and dimensional stability

• Good resistance to thermal cycling

• Available in dense and insulating refractory configurations

• Suitable for industrial furnaces and ceramic kilns

• Good chemical stability in appropriate furnace atmospheres

• Custom dimensions and refractory shapes may be available

• COA and technical documentation available as applicable

Property	Typical Specification
Product Name	Mullite Brick
Material	Mullite Refractory
Chemical Composition	Primarily alumina (Al₂O₃) and silica (SiO₂)
Ideal Mullite Formula	3Al₂O₃·2SiO₂
CAS Number	1302-93-8 (mullite)
Appearance	White, cream, or light-colored refractory brick
Alumina Content	Commonly approximately 60–80 wt%, grade dependent
Silica Content	Grade and composition dependent
Bulk Density	Approximately 1.8–2.8 g/cm³, depending on brick type
Maximum Service Temperature	Commonly approximately 1,400–1,700°C, grade and conditions dependent
Refractoriness	High-temperature refractory performance
Thermal Expansion	Low relative to many conventional refractory materials
Thermal Conductivity	Grade, density, and temperature dependent
Porosity	Varies by dense or insulating grade
Thermal Shock Resistance	Generally good; depends on formulation and porosity
Available Types	Dense mullite brick, insulating mullite brick, custom refractory shapes
Documentation	COA, SDS, and technical data as applicable

Dense Mullite Brick

Designed for applications requiring higher mechanical strength, abrasion resistance, and structural stability at elevated temperatures.

Insulating Mullite Brick

Lightweight refractory brick designed to reduce heat loss in furnaces and kilns. Thermal conductivity and maximum service temperature depend on grade and density.

High-Alumina Mullite Brick

Designed for high-temperature environments requiring a controlled alumina-rich composition and good refractory performance.

Custom Mullite Refractory Shapes

Custom dimensions, machined shapes, and application-specific refractory components may be available according to furnace design and installation requirements.

1. What is mullite brick?

Mullite brick is a refractory product made primarily from mullite, an alumina-silica ceramic phase. It is used in high-temperature furnaces, kilns, and thermal processing equipment.

2. What is mullite brick used for?

Typical applications include ceramic kilns, industrial furnaces, heat-treatment equipment, refractory linings, laboratory furnaces, and high-temperature processing systems.

3. What temperature can mullite brick withstand?

Depending on its formulation and design, mullite brick may be rated for service temperatures around 1,400–1,700°C. The actual continuous operating limit must be confirmed for the specific grade and operating conditions.

4. What is the difference between dense and insulating mullite brick?

Dense mullite brick prioritizes mechanical strength and structural durability. Insulating mullite brick has a lighter, more porous structure designed to reduce heat transfer and furnace energy consumption.

5. Is mullite brick resistant to thermal shock?

Mullite generally has low thermal expansion and good thermal stability, which can help it withstand temperature cycling. Actual thermal shock performance depends on porosity, formulation, brick geometry, and heating or cooling rates.

6. Can REG Metals supply custom mullite brick?

REG Metals can source mullite brick according to required dimensions, alumina content, density, porosity, thermal conductivity, and temperature rating, subject to availability. Technical documentation and COA may be available as applicable.