High-Temperature Resistance Characteristics of Corundum-Based Porous Ceramic Balls
A brief introduction to the high-temperature resistance characteristics of corundum-based porous ceramic balls.
High-Temperature Resistance Characteristics of Corundum-Based Porous Ceramic Balls
Corundum-based open-pore ceramic balls feature α-Al₂O₃ (the corundum phase) as their primary constituent, typically comprising over 90% of the composition. Leveraging the high melting point, exceptional hardness, and chemical stability of corundum, these materials exhibit superior thermal resistance under high-temperature operating conditions.
High-Temperature Stability
Corundum possesses a melting point of 2050°C; consequently, within the temperature range typical of industrial reactors, it undergoes virtually no softening or phase transformation.
Temperature Range | Performance |
Room Temp. – 800°C | Stable performance; no change in strength or hardness |
800-1200℃ | Good performance; unaffected by prolonged use |
1200-1500℃ | Tolerable; suitable for cracking furnaces and hot blast stoves |
Thermal Shock Resistance
Corundum ceramic balls can withstand rapid heating and cooling shocks of 100–200°C without cracking. Their coefficient of thermal expansion is approximately 7–8 × 10⁻⁶/°C; this thermal shock resistance can be further enhanced by optimizing the grain structure.
High-Temperature Mechanical Properties
Temperature | Compressive Strength Retention Rate |
Room Temperature | 100% |
600℃ | 85%-90% |
1000℃ | 70%-80% |
1200℃ | 50%-70% |
Its absolute strength remains higher than that of mullite-based or cordierite-based ceramic balls.
High-Temperature Chemical Stability
Corundum is one of the most chemically stable oxides:
Resistant to both oxidation and reduction
Resistant to acids and alkalis, remaining inert toward most media
Suitable for demanding operating conditions, such as those involving hydrogen-rich, sulfur-containing, or corrosive gases
Comparison with Other Materials
Material | Max. Service Temperature | Thermal Shock Resistance | High-Temperature Strength |
Corundum-based | 1300-1500℃ | Good | High |
High-Alumina | 1100-1300℃ | Fair | Moderate |
Mullite-based | 1200-1400℃ | Good | Moderate |
Cordierite-based | 1000-1200℃ | Excellent | Lower |
Typical Applications
Application Scenario | Temperature | Key Requirements |
Ethylene Cracking Furnace | 900-1100℃ | Thermal Shock Resistance, High-Temperature Strength |
Hot Blast Stove | 1000-1300℃ | Erosion Resistance, Creep Resistance |
Hydrogenation Reactor | 400-600℃ | Hydrogen Corrosion Resistance, Chemical Inertness |
Selection Recommendations
For operating temperatures exceeding 1100°C—or in applications involving severe temperature fluctuations—corundum-based materials are the preferred choice.
For operating conditions below 800°C, high-alumina or mullite-based materials offer a more cost-effective solution.
Summary
Corundum-based perforated ceramic balls are capable of withstanding operating temperatures ranging from 1300°C to 1500°C. Characterized by high strength retention at elevated temperatures, excellent thermal shock resistance, and chemical stability, they represent an ideal choice for reactor support in demanding, high-temperature environments. Material selection should be determined through a comprehensive assessment of process temperature, temperature fluctuation amplitude, and the properties of the process medium. We are a China-based supplier of industrial ceramics; for further information, please contact us via email at annayu@169chem.net or via WhatsApp at +8618909016373.