Sagger Corundum Mullite
Sagger Corundum Mullite is a premium, high-purity ceramic container used in kilns and furnaces for thermal processing of sensitive or advanced materials. It is composed of a blend of high-purity Alumina (Al2O3 – Corundum) and Mullite (3Al2O3-2SiO2). This composite formulation is engineered to provide a superior combination of high refractoriness, exceptional hot strength, high thermal shock resistance, and minimal contamination compared to standard fireclay or pure Mullite saggers.
Main Chemical Compositions & Categories
The material is a dense, sintered composite designed to leverage the low thermal expansion of Mullite and the high purity/refractoriness of Corundum. The Al2O3 content is significantly higher than in standard Mullite.
| COMPONENT | COMPOSITION | PRIMARY ADVANTAGE |
| Corundum Aggregate | High-Purity Al2O3 | Maximum refractoriness and hot strength. |
| Mullite Matrix | 3Al2O3-2SiO2 | Excellent thermal shock resistance and low thermal expansion. |
| CLASSIFICATION | Al2O3 Content | TYPICAL MST |
| Corundum Mullite | 75% to 85% | ~1700°C to 1750°C |
Key Properties and Performance
| PROPERTY | TYPICAL PERFORMANCE | MECHANISM OF ADVANTAGE |
| Refractoriness | VERY HIGH | Significantly higher than standard fireclay or Cordierite, allowing use in advanced sintering processes. |
| Thermal Shock | EXCELLENT | The Mullite phase ensures the sagger can withstand the high-temperature gradients and rapid cycling of continuous kilns. |
| Hot Strength/Creep | SUPERIOR | High Al2O3 content minimizes slumping and deformation under the load of stacked wares at peak T. |
| Chemical Purity | HIGH | Low flux content reduces the risk of chemical attack on the sagger or contamination of the fired product. |
Sagger Corundum Mullite
Advantages and Key Characteristics
Corundum Mullite Saggers are an upgrade from lower-grade materials, specifically chosen for high-value products that require a high, stable temperature and zero tolerance for contamination or slumping.
- Extended Service Life: The combination of superior thermal shock resistance (Mullite) and high RUL (Corundum) results in fewer failures, reduced replacement costs, and longer campaign life compared to less robust saggers.
- Structural Integrity under Load: These saggers maintain excellent dimensional stability and resistance to creep (slumping under load) even at temperatures approaching 1750°C. This is critical for high-density kiln loading and large/heavy wares.
- Reduced Contamination Risk: The high purity of the raw materials means minimal volatile impurities (like iron oxide or alkalies) are released during firing, protecting sensitive electronic or optical ceramics.
- Energy Efficiency: While still porous enough for temperature uniformity, the dense structure resists mechanical wear and erosion, maintaining structural integrity over many cycles.
Typical Industries and Applications
This premium sagger is used for critical and high-value thermal processes:
- Advanced Ceramics: Sintering complex shapes, high-purity electronic ceramics (e.g., substrates, insulators), and ceramic armor.
- Metallurgy: High-temperature sintering of powdered metals, refractory metals, and specialized alloys under controlled atmospheres.
- Single Crystal Growth: Used as a container or holder in systems requiring extreme temperature stability and chemical inertness.
- Abrasives: Firing high-purity synthetic abrasives where firing uniformity is key.
Selection and Maintenance
Selection is based on the maximum temperature required and the sensitivity of the product:
- Corundum Mullite is the ideal choice when the firing temperature exceeds the limits of Cordierite/Fireclay (1450°C) but the system still involves frequent thermal cycling.
- High-Purity Alumina (99.8%) Crucibles are used if the MST exceeds 1750°C or if absolute minimal contamination is required (often at the expense of thermal shock resistance).
Technical Guidance: Due to their high strength, these saggers can typically be stacked higher and loaded heavier than standard fireclay saggers. They should be pre-fired or conditioned before use with sensitive wares to ensure all initial material volatiles are removed.
✨ Customization Services
We offer product customization services, allowing you to tailor the appearance, dimensions, or specific markings of items like refractory shapes or bricks. This includes options for incorporating specific geometric requirements to ensure seamless integration into your process systems.
🔬 Sampling for Testing & Validation
Free product samples are available for thorough testing and validation. This allows you to confirm the quality, compatibility, and performance of our materials—such as specific bricks, castables, or raw materials—before committing to a full order.
💡 Expertise in Refractory Solutions
Leverage our deep expertise to receive detailed, application-specific refractory solutions. We move beyond just selling products by providing comprehensive plans that encompass material selection, installation guidance, and performance optimization to maximize the lifespan and efficiency of your high-temperature processes.
Rabatec products are exclusively manufactured in facilities that have achieved rigorous ISO certifications across Quality (ISO 9001), Environmental Management, and Occupational Health & Safety. This commitment ensures every product, from refractory bricks to specialized equipment, meets the highest global benchmarks for performance, sustainability, and workplace safety.
📦 Logistics Excellence: Shipping, Packaging, and Marking
Minimizing Risk: We manage all logistics to minimize handling touchpoints and transit shock. Our carriers are pre-vetted for their experience in transporting heavy, fragile, and sensitive industrial materials.
Traceability: Every shipment includes comprehensive documentation and tracking information, providing end-to-end visibility and ensuring precise delivery coordination for your site.
Protection is Paramount: Our packaging strictly follows industry standards to prevent damage, corner chipping, and moisture absorption—especially critical for materials like Basic Refractory Bricks and Refractory Mortars & Mixes.
Robust Palletization: Products are secured on fumigated, high-strength export pallets (e.g., 1100x950mm or similar sturdy dimensions) using heavy-duty strapping and durable protective wrapping (polyethylene sheeting, cardboard, etc.) to withstand long-distance travel and multiple loadings.
Moisture Control: Sensitive materials are protected with appropriate sealing and, where necessary, desiccants or moisture-vapor proof enclosures to maintain the product's integrity until installation.
Clear Identification: All outer packaging is clearly marked on multiple sides with large, legible text for immediate identification and safe handling.
Full Traceability: Markings include all essential data points: Product Name, Quality Grade, Batch Number, Quantity, Net/Gross Weight, Order Number, and the Final Destination/Construction Area. This ensures every pallet can be accounted for and correctly staged upon arrival.
Safety & Compliance: We adhere to all regulatory requirements for marking, labeling, and placarding—especially for any items classified as Dangerous Goods—to ensure full compliance with international and domestic transport regulations.
❓ Frequently Asked Questions (FAQ)
Question | Elaborated Answer |
Q: What is the Refractoriness Under Load (RUL) of your refractories? | A: Refractoriness Under Load (RUL) is a critical property that defines the maximum temperature our materials can withstand while under compressive stress before deforming (softening). Since we offer a wide range of materials—from Alumina-Silicate Bricks to high-performance Silicon Carbide Bricks—the RUL varies significantly. For specific product data, please refer to the product data sheet or submit a quote request for the material you are interested in. |
Q: Where are the Rabatec refractories and materials produced? | A: Our products are primarily sourced from specialized manufacturing plants in China. Crucially, these facilities have all undergone rigorous audits and achieved comprehensive ISO certifications (Quality, Environment, and Safety), ensuring that production adheres to the highest global standards for consistency and performance. |
Q: What refractory materials does the company offer? | A: We supply a comprehensive portfolio of advanced refractory solutions, including: Shaped Products: Alumina & Silica Bricks, Basic & Specialized Bricks (e.g., Magnesia), SiC & Structural Ceramics, and Precast Shapes. Monolithic Products: Refractory Castables, Mixes & Mortars. Insulation: Insulation Fibre and High-Performance Insulation Products. |
Q: How should I choose the appropriate refractory material for my application? | A: Selecting the correct refractory is paramount to process efficiency. The choice depends on three key factors: 1. Operating Environment: Maximum process temperature and thermal cycling (shock). 2. Chemical Attack: Type of slag, molten metal, or corrosive gas being handled (acidic, neutral, or basic). 3. Mechanical Stress: Abrasion, erosion, and static load requirements. We recommend utilizing our detailed refractory solutions service to consult with our engineers for an optimized, application-specific recommendation. |
Q: Which monolithic material should I choose when patching an existing lining? | A: For patching and minor repairs, the ideal monolithic material depends on the parent lining material, the patching depth, and the need for a rapid return to service. Common choices include: Refractory Mortars & Mixes (for minor joints/surfaces) or Plastic Refractories (for areas requiring physical compaction). Always choose a patch material chemically compatible with the existing lining to ensure proper bonding and service life. |
Q: Can I receive product samples before placing a major order? | A: Yes. We gladly provide product samples for your internal testing and validation purposes. This ensures you can confirm the quality, composition, and fit of the material—such as our Refractory Castables or Alumina-Silicate Bricks—in your specific operational environment before committing to a bulk purchase. |
Q: Do you provide certifications to verify material quality? | A: Absolutely. We provide product-related inspection certificates and quality assurance documentation upon request. This verifies that your order has passed all internal quality control checks and meets the required material specifications and industry standards. |
Q: What measures are taken for product protection during transport? | A: We ensure quick, reliable transport by using robust, industrial packaging that strictly follows industry standards. This includes high-strength palletization, heavy-duty strapping, and weather-resistant wrapping to protect fragile items like bricks and mixes from corner chipping, mechanical damage, and moisture during transit. |
