15mm*11mm Pressureless Sintered SiC Roller
15*11mm Pressureless Sintered SiC Roller represents a precision thin-walled hollow tube specification that achieves an ideal balance among material density, mechanical load capacity, and structural lightweighting. This product plays a critical role in applications such as thermocouple protection, high-temperature roller hearth transmission, heat exchanger tubes, and high-temperature corrosive media transport.
Manufacturing Process
Raw Material System
Preparation uses high-purity α-SiC submicron powder (SiC content ≥98%, typically ≥99%) as the main raw material, supplemented with small amounts of sintering aids and processing additives. Particle size D₅₀ is controlled between 0.5–0.6 μm with powder purity above 99%.
Forming Processes
- Extrusion: Plasticized feedstock forced through precision tubular dies for continuous production
- Cold Isostatic Pressing (CIP): Isotropic pressure of 100–300 MPa for uniform density and isotropy
- Extrusion-CIP Combined Process: Ideal solution combining forming efficiency with density uniformity
- Slip Casting: Capillary absorption method for small batches and special shapes
Sintering Process
Pressureless sintering is carried out in non-oxidizing atmosphere at 2000–2150°C, relying on solid-state or liquid-phase diffusion for densification without external pressure. This process is not limited by product shape or size, making it the mainstream route for mass production.
Post-Treatment and Precision Control
After sintering, rods undergo precision grinding and polishing to achieve target dimensions with bore diameter tolerance ±0.01 mm, cylindricity ≤0.004 mm, concentricity 0.003 mm, and surface roughness down to Ra 0.5 μm.
Physicochemical Properties
Mechanical Properties
| Property |
Value |
| Hardness |
Mohs 9.5, Shore 115 HS, Microhardness 2200–3000 HV |
| Density |
≥3.10 g/cm³ (up to 3.18–3.20 g/cm³) |
| Elastic Modulus |
400–430 GPa |
| Flexural Strength (RT) |
350–400 MPa |
| Flexural Strength (1200°C) |
370–420 MPa |
| Compressive Strength |
>2500 MPa (up to 3900 MPa) |
| Fracture Toughness |
3.5–4.3 MPa·m¹/² |
| Porosity |
<0.2% |
Thermal Properties
| Property |
Value |
| Maximum Service Temperature |
1600–1650°C (oxidizing), up to 2200°C short-term |
| Thermal Conductivity (RT) |
120–200 W/(m·K) |
| Thermal Conductivity (1200°C) |
~33 W/(m·K) |
| Coefficient of Thermal Expansion |
(3.6–4.8)*10⁻⁶/K (20–1200°C) |
| Thermal Shock Resistance |
Excellent (withstands >400°C/min) |
Chemical & Electrical Properties
SSiC exhibits outstanding corrosion resistance, forming a dense SiO₂ protective layer under high-temperature oxidizing conditions. Except for hydrofluoric acid and molten strong alkalis, it shows excellent chemical stability. As a wide-bandgap semiconductor, it is non-magnetic and non-conductive.
Application Scenarios
- Thermocouple Protection Tubes: High-temperature furnaces, salt baths, glass melting
- High-Temperature Roller Hearth Kiln Transport: Technical ceramics, battery materials, refractories
- Heat Exchangers and Recovery Systems: Waste heat recovery at 800–1000°C
- Corrosive Media Transport: Chemical, metallurgical, and new energy sectors
- Mechanical Seals and Bearings: Medium-diameter rotating equipment
- Semiconductor and Photovoltaic Manufacturing: Ultra-pure material delivery systems
Performance Advantages
Core Performance Comparison
| Property |
SSiC |
RBSiC |
R-SiC |
Metal |
| SiC Content (%) |
≥98 |
80–90 |
~97 |
0 |
| Max Service Temp (°C) |
1600–1650 |
1380 |
1600+ |
≤600–900 |
| Flexural Strength RT (MPa) |
350–400 |
250 |
~100 |
200–600 |
| Thermal Conductivity RT (W/m·K) |
120–200 |
130–240 |
100–150 |
15–45 |
| Relative Service Life |
1 (baseline) |
~0.2 |
~0.067 |
Much lower |
Core Advantages Summary
- Free-silicon-free structure overcoming temperature and corrosion limits
- Excellent high-temperature mechanical property retention
- Outstanding corrosion and oxidation resistance
- Extremely long service life and cost-effectiveness
- Lightweight construction and energy savings
- High thermal conductivity and thermal shock resistance
- Precision control capability for stringent applications
- Chemical inertness and low contamination for ultra-pure requirements
Selection Recommendations
For combined conditions of high temperature (>1380°C) and highly corrosive media, SSiC rods are the necessary choice. For medium-temperature applications, RBSiC offers cost advantages. SSiC provides irreplaceable advantages in extreme hardness, high-temperature strength retention, and overall service life.
For further information or to discuss your specific needs, please contact us directly.
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