Graphite Rigid Felt
Graphite Rigid Felt produced by Max Graphite is an advanced insulation material engineered for structural integrity in extreme thermal environments. Manufactured from high-purity carbon or graphite fibers and rigidized through specialized processes, it provides exceptional thermal insulation and stability up to 3000°C. Our product range includes Long and Short Fiber Rigid Graphite Felts based on PAN, Rayon, and Pitch Carbon Fiber, each optimized for specific heat insulation of Heat Treatment Vacuum Furnaces, Semiconductor Induction Furnaces, Solar CZ Furnaces, and more.
Specification of
Graphite Rigid Felt
Max Graphite's rigid felt is characterized by high purity, uniform structure, and consistent performance. Standard specifications vary based on fiber type and structure.
Typical Grade Specifications: All values are typical; custom grades available on request.
Certifications:
Size of
Graphite Rigid Felt
We provide standard boards and full custom machining services to meet precise furnace and equipment designs.
Contact us for a detailed stock list or to discuss your custom size requirements.
What is Graphite Rigid Felt?
Graphite Rigid Felt is a board-like graphite insulation material created by rigidizing and graphitizing a felt of carbon or graphite fibers. Unlike flexible graphite soft felt, it is a semi-structural solid board that maintains its shape under load, offering higher mechanical strength while retaining the excellent thermal insulation, thermal shock resistance, and high-temperature stability.
Max Graphite's Product Differentiation:
- By Fiber Structure: Long Fiber Graphite Rigid Felt works for Resistance Furnace heat insulation. Short Fiber Rigid Graphite Felt is the right insulation material for Induction Furnaces.
- By Fiber Material: We produce PAN, Rayon, and Pitch based Graphite Rigid Felt. Each precursor imparts distinct thermal, mechanical, and purity characteristics, making them suitable for different high-end applications as detailed in the application section.
Properties of Graphite Rigid Felt
- Superior Thermal Insulation: Low thermal conductivity minimizes heat loss and improves furnace efficiency.
- Structural Rigidity: Can be machined into complex, self-supporting components.
- Ultra-High Temperature Stability: Maintains properties in inert/vacuum atmospheres up to 3000°C.
- Exceptional Thermal Shock Resistance: Withstands rapid temperature cycling without cracking.
- Low Thermal Mass: Enables faster furnace cycling, reducing energy consumption and process time.
- High Purity & Cleanliness: Low ash content prevents contamination in sensitive processes like semiconductor growth.
- Good Machinability: Can be precision-machined into tight-tolerance parts.
Production Process of Graphite Rigid Felt
The manufacturing involves transforming precursor fibers into a rigid, high-purity graphite structure.
- Fiber Precursor Selection: Choice of PAN (Polyacrylonitrile), Rayon, or Pitch fibers, determining the base material properties.
- Forming: Long Fiber Soft Graphite Felts are laminated and pressed into a stable Rigid Graphite Insulation Board and Cylinder. Chopped Short Carbon Fiber is vacuum formed into Short Fiber Graphite Rigid Insulation Board, Cylinder and shapes.
- Carbonization/Graphitization: The board undergoes high-temperature pyrolysis (carbonization) and subsequent graphitization (up to 2400°C+), converting it into a pure, rigid graphite-carbon composite.
- Machining: Precision machining to customer sizes and shapes: insulation board, curve, and cylinder.
- Coating: Graphite painting is applied to rigid felt to prevent fiber drop; lifetime can be increased greatly.
- Purification: Final high-temperature purification at 2600°C to reduce impurities to under 20 ppm.
Applications
Heat Treatment
High-Temperature Vacuum Furnace Heat Insulation—linings, baffles, and thermal breaks in vacuum furnaces and graphite furnaces. Rigid graphite felt is the only right material to work as heat insulation layer in vacuum furnace when temperature is over 1600°C; it can work when the furnace temperature increases up to 3000°C in inert gas.
Semiconductor Industry
Pitch-Based Rigid Felt is predominantly used in silicon crystal growth furnaces (Czochralski) and epitaxial resistance furnaces for first-generation silicon semiconductors. Rayon-Based Short Fiber Rigid Felt is essential for insulation in third-generation silicon carbide (SiC) substrate and epitaxial induction furnaces.
Solar Silicon CZ Furnace
PAN-Based Graphite Rigid Felt, known for its excellent cost-performance ratio, mature process, and long oxidation life, is widely applied in PV crystal pullers, diffusion furnaces, and various high-temperature heat treatment furnaces.
Industrial Furnaces
Used as structural insulation liners, baffles, and heating element supports in vacuum furnaces, sintering furnaces, and graphitization furnaces.
Aerospace
Components for thermal protection and testing equipment.
Related Materials and Products
Max Graphite supplies a complete thermal solutions portfolio.
Isostatic Graphite
Graphite Foil
Graphite Soft Felt
Short Fiber Graphite Rigid Felt
CFC Channels
PAN-Based Graphite Felt
Pitch-Based Graphite Felt
Rayon-Based Graphite Felt
Graphite-Coated Rigid Felt
SR4 - Short Fiber Rigid Insulation Felt
Rigid Graphite Felt Boards and Cylinders