Material Overview
Silicon Carbide (SiC) is a high-performance advanced ceramic material renowned for its exceptional hardness (second only to diamond), thermal stability (up to 1,650°C), and resistance to wear, corrosion, and oxidation. Composed of silicon and carbon atoms in a covalent lattice, SiC ceramics are widely used in aerospace, semiconductor manufacturing, energy systems, and industrial machinery due to their unique combination of mechanical and thermal properties.
Technical Data Table
| Property | Reaction Bonded Silicon Carbide (RBSiC) | Sintered Silicon Carbide（SSiC） |
| Density (g/cm³) | >3.1 | >3.13 |
| Flexural Strength (MPa) | 462 | >480 |
| Modulus of Elasticity (GPa) | 393 | 410 |
| Thermal Conductivity (W/m·K) | 150 | 120-150 |
| Max. service temperature (℃) | 1300 | 1650 |
Silicon carbide is also known as “superhard ceramic” and is a common material for ceramic valve seats,ceramic plungers,ceramic nozzles, and ceramic wear parts.
Key Features
- Ultra-High Hardness: Mohs hardness of 9.5, ideal for abrasive environments like mining and cutting tools.
- Thermal Conductivity: Ranges from 120–150 W/mK, enabling efficient heat dissipation in high-power electronics.
- Chemical Inertness: Resists acids (e.g., HCl, H₂SO₄), alkalis, and molten metals, ensuring longevity in corrosive settings.
- Oxidation Resistance: Maintains structural integrity at 1,600°C in air due to a protective SiO₂ surface layer.
Applications
- Semiconductor: Wafer handling arms, plasma etching components, and susceptors for CVD reactors.
- Energy: Heat exchangers, burner nozzles, and turbine blades in gas turbines.
- Industrial: Wear-resistant liners for pumps, seals, and valves in chemical processing.
- Automotive: Brake discs and bearings for electric vehicles (EVs) due to lightweight and thermal stability.
Manufacturing Techniques
- Hot Pressing: Produces ultra-dense ceramics (>99% density) for high-stress applications.
- CNC /Grinding: For precise dimensional torlerance.
- Additive Manufacturing: 3D-printed SiC parts samples for complex geometries in our supporting partners help.
Silicon carbide outperforms metals due to its ultra-high thermal stability (1,650°C vs. 500°C for stainless steel) and oxidation resistance. For example, SiC burner nozzles in gas turbines reduce maintenance costs by 70% compared to nickel alloys, while its low thermal expansion (4.0×10⁻⁶/°C) prevents cracking under thermal cycling.
Silicon carbide ceramics have excellent wear resistance, and their hardness is second only to diamond. They can effectively resist high-speed particle erosion, mechanical friction and impact wear. Under the same working conditions, their wear resistance far exceeds that of steel and traditional oxide ceramics such as alumina (Al2O3) and zirconia (ZrO2), and their service life can be extended several times. They are especially suitable for harsh wear environments such as mining, metallurgy, and electricity, greatly reducing the frequency and cost of equipment maintenance.
- Chemical Processing: SiC-lined pipes transport corrosive media (e.g., sulfuric acid) with a service life exceeding 5 years, reducing replacement frequency by 80%.
- Semiconductor: SiC components resist plasma erosion in etching chambers, extending tool lifespan by 50%.
- Energy: Molten salt reactors use SiC seals to prevent leakage in high-temperature, corrosive environments.
RBSC offers cost efficiency and complex shape fabrication without machining. By infiltrating molten silicon into porous carbon preforms, RBSC achieves flexural strengths up to 462 MPa and densities >95%. It is widely used in large-scale components like kiln furniture and rocket nozzles.