Cordierite and Silicon Carbide: A Comparison of the Properties and Applications of Two Major Carrier Materials
A brief introduction to two major carrier materials: cordierite and silicon carbide, based on their properties and applications.
Cordierite and Silicon Carbide: A Comparison of the Properties and Applications of Two Major Carrier Materials
Cordierite and silicon carbide constitute the two major technical systems for honeycomb ceramic carriers.
Basic Material Properties
Cordierite: Its chemical composition is 2MgO•2Al₂O₃•5SiO₂, belonging to the orthorhombic crystal system. Its main material characteristic is its extremely low coefficient of thermal expansion (1.0-1.5×10⁻⁶/°C), which allows it to maintain structural integrity under drastic temperature changes.
Silicon Carbide: Its chemical formula is SiC. It is commonly prepared using two processes: recrystallized silicon carbide and reaction-sintered silicon carbide. Its core characteristics are high thermal conductivity (15-25 W/m•K) and high-temperature stability, with an operating temperature exceeding 1600°C.
Key Performance Parameter Comparison
Performance Indicators | Cordierite | Silicon Carbide |
Density | 2.0-2.1 g/cm³ | 2.5-2.7 g/cm³ |
Maximum Operating Temperature | ≤1350°C | ≥1600°C |
Coefficient of Thermal Expansion | 1.0-1.5×10⁻⁶/°C | 4.0-4.5×10⁻⁶/°C |
Thermal Conductivity | 1-2 W/m·K | 15-25 W/m·K |
Compressive Strength | 25-40 MPa | 80-120 MPa |
Material Cost | Low | High (approximately 3-5 times that of cordierite) |
Application Scenarios
Cordierite Application Scenarios
Gasoline vehicle three-way catalytic converter: Almost all use cordierite carriers
Light-duty diesel vehicle DOC/SCR carrier: Standard configuration
Light-duty diesel vehicle DPF: Meets basic filtration requirements
Industrial catalytic carrier: Medium and low temperature catalytic reactions
Silicon carbide Application Scenarios
Heavy-duty diesel vehicle DPF: Mainstream choice, accounting for over 90%
High-performance gasoline vehicle GPF: High-end model configuration
Hybrid vehicle aftertreatment: To handle frequent start-up Thermal Shock During Shutdown
Filtration Systems Requiring Rapid Regeneration
Core Logic of Material Selection
Choosing Cordierite: Operating temperature not exceeding 1350°C; relatively mild thermal shock; cost-sensitive large-scale applications; requiring complex pore structure design.
Choosing Silicon Carbide: Operating temperature exceeding 1350°C; facing severe thermal shock (e.g., DPF active regeneration); requiring rapid heat transfer; extremely high structural strength requirements.
Differences in Manufacturing Processes
Cordierite Process Characteristics:
Lower raw material cost, mature extrusion process, enabling large-scale continuous production. Wall thickness can reach 3-4 mil (approximately 0.076-0.10 mm), with a wide pore density range (100-1200 cpsi). Sintering temperature approximately 1400°C.
Silicon Carbide Process Characteristics:
Higher raw material cost, typically employing segmented sintering or reactive sintering. To compensate for the higher coefficient of thermal expansion, small unit splicing structures are often used. Ultra-thin wall thickness (2-3 mil) can be achieved, but requires strict process control.
Summary
Cordierite, with its extremely low coefficient of thermal expansion, achieves excellent thermal shock resistance and boasts a significant cost advantage, dominating the gasoline and light-duty diesel vehicle markets. Silicon carbide, with its high thermal conductivity and high-temperature resistance, is the preferred choice for high-performance applications such as DPFs in heavy-duty diesel vehicles, addressing extreme operating conditions. The two materials have a clear division of labor: cordierite is chosen for conventional applications to control costs, while silicon carbide is chosen for high-end demands to ensure performance. We are a Chinese manufacturer of honeycomb ceramics. For more information, please contact us via email at annayu@169chem.net or WhatsApp at +8618909016373.