Sintered Mullite
SEPPE Sintered Mullite is an alumina-silica refractory raw material series supplied in selected grades for castables, shaped refractories, ceramic kiln furniture, foundry materials and high-temperature filler systems. The range includes M45, M55, M60 and M70, helping buyers compare chemistry, density, particle size and application direction before selecting a detailed product grade.
M45 / M55 / M60 / M70
One series page for quick grade selection
Use this page as a summary before entering each product detail page. M45, M60 and M70 are usually compared by alumina level and low-iron control. M55 is presented as a cost-performance high wear resistant mullite product and should be selected by its structure, density and application fit.
M45
Economical mullite grade
M55
Cost-performance wear grade
M60
Higher alumina refractory grade
M70
High alumina mullite grade
Regular Alumina Grade View
Typical Al2O3 comparison for M45, M60 and M70.
Higher alumina
higher grade
M55 note: M55 is a separate cost-performance high wear resistant mullite product. Its Fe2O3 value is higher than the low-iron grades, so it is selected by wear resistance, dense structure and application fit rather than placed on the regular alumina-grade chart.
Grade Selection Guide
M45
Cost-effective base grade
Balanced alumina-silica chemistry for common refractory castables, bricks and medium-temperature systems.
M55
Cost-performance high wear resistant mullite
Dense grey block, grit or powder grade for castable, moulding, foundry and casting applications where low-iron color control is not the priority.
M60
Higher alumina grade
Suitable for formulations requiring stronger thermal stability and higher alumina content than M45.
M70
High alumina mullite
Used where higher Al2O3 level, lower silica level and demanding high-temperature performance are required.
Typical Specification Comparison
| Grade | Al2O3 | SiO2 | Fe2O3 | TiO2 | Bulk Density | Main Positioning |
|---|
| M45 | 45.0% / 44.0% min | 47.2% | 1.3% / 1.5% max | 2.7% | 2.55 g/cm3 min | Economic alumina-silica grade |
| M55 | 55.81% | 34.80% | 4.57% | 2.74% | 2.60 g/cm3 | Cost-performance wear grade |
| M60 | 60.0% / 58.0% min | 34.2% | 1.3% / 1.5% max | 3.0% | 2.65 g/cm3 min | Higher alumina refractory grade |
| M70 | 70.0% / 68.0% min | 22.4% | 1.3% / 1.5% max | 3.0% | 2.7 g/cm3 min | High alumina mullite grade |
Key Technical Indicators
45%-70%
Al2O3 range
From economic M45 to high alumina M70.
1.5% max
Fe2O3 control
Typical max value for M45, M60 and M70.
0.05%-0.07%
Low alkali grades
Na2O and K2O control helps high-temperature stability.
4.57%
M55 Fe2O3
Higher than low-iron grades, positioned for wear resistance and cost-performance fit.
Particle Size and Supply Forms
M45 common sizes
0.1-0.3 mm, 0.3-0.8 mm, 0.5-1.0 mm, 0.7-1.5 mm, 2-5 mm, 30-60 mesh, -200 mesh, -325 mesh.
M55 supply forms
Grey or dark grey block, grit and powder. Particle size can be discussed according to moulding, castable, foundry or casting use.
M60 standard sizes
0-0.5 mm, 0-1 mm, 1-3 mm, 3-6 mm, 5-8 mm, -200 mesh, -325 mesh.
M70 broad size range
Narrow granules and mesh grades such as 0.1-0.3 mm, 0.18-0.5 mm, 0.7-1.5 mm, 2-5 mm, 16-30 mesh, 30-60 mesh, -120 mesh, -200 mesh and -325 mesh.
Applications
Refractory castables
Aggregate and powder grades for castable and low-cement castable formulations.
Shaped refractories
Mullite bricks, refractory blocks and shaped high-temperature products.
Ceramic kiln furniture
Setters, supports and ceramic components exposed to repeated thermal cycling.
Foundry and casting
High-temperature filler, wear resistant mixes and industrial refractory systems.
Available Technical Files
Packing and Storage
Packing
Commonly supplied in jumbo bags or customized export packing according to order requirement.
Storage
Store in a dry and ventilated environment. Keep original sealed packaging before use.
Documents
TDS, COA, particle size information and sample support can be provided for confirmation.
FAQ
? Is this page for one product or a product series?
This page is a Sintered Mullite series summary. It helps customers compare M45, M55, M60 and M70 before opening the detailed product page for each grade.
? How should M45, M60 and M70 be selected?
They are mainly selected by alumina content, chemistry control, required service temperature, refractory formulation and cost target.
? Why is M55 described separately?
M55 is positioned as cost-performance high wear resistant mullite. Its Fe2O3 level is higher than the low-iron grades, so selection depends on wear resistance, density, structure, apparent porosity and specific application conditions.
? Can particle size be customized?
Yes. Standard sizes and customized particle size distribution can be discussed according to refractory formulation, forming process and final service condition.
Need Help Selecting Sintered Mullite Grade?
Contact SEPPE for M45, M55, M60 and M70 grade selection, TDS, COA, samples, particle size discussion and bulk order support.
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