1. What Is Rayon Soft Graphite Felt?
Rayon soft graphite felt is a high-performance thermal insulation material manufactured from viscose fibers derived from natural cellulose. The raw material – α-cellulose extracted from wood pulp, plants, or processed cotton linters – is converted into man-made fibers through wet spinning. These precursor fibers are then processed through a carefully controlled sequence of needling, pre-oxidation, carbonization, and ultimately high-temperature graphitization at over 2000°C in a vacuum or inert gas atmosphere–.
The resulting material is a soft, flexible, lightweight felt with a porous fiber network structure. Unlike rigid graphite boards, soft graphite felt can be easily cut, folded, and shaped to fit complex thermal field geometries–. This flexibility, combined with its exceptional thermal insulation properties, makes it an ideal choice for high-temperature furnace applications, particularly in the photovoltaic monocrystalline silicon industry–.
2. Raw Materials and the Production Process
rayon graphite felt
The production of Rayon soft graphite felt begins with viscose fiber – a regenerated cellulose fiber made from natural renewable resources. The precursor felt is produced using specialized needling techniques to create a uniform fiber network–. From there, the material undergoes a multi-stage thermal treatment:
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Carbonization: The precursor felt is heated to approximately 1200°C in an oxygen-free environment, converting the cellulose fibers into carbon fibers.
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Graphitization: The carbonized felt is then heated to temperatures of 2200°C to 2600°C – or even higher – in a vacuum or inert gas atmosphere–. This high-temperature treatment transforms the disordered carbon structure into a highly ordered graphitic structure, dramatically improving thermal stability and purity.
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Purification (optional): For applications requiring ultra-high purity, additional purification steps can reduce ash content to as low as 20–200 ppm.
The entire production chain – from precursor fiber to finished graphite felt – demands rigorous quality control at every stage to ensure product consistency and reliability. CFCCARBON‘s manufacturing facilities are equipped to handle this complete process, delivering Rayon soft graphite felt with stable, reliable quality.
3. Product Performance: What Makes Rayon Soft Graphite Felt Superior?
Rayon-based graphite felt offers several distinct performance advantages that make it particularly well-suited for high-temperature insulation applications–:
Superior Thermal Insulation: Rayon soft graphite felt achieves remarkably low thermal conductivity – typically below 0.5 W/m·K at 1000°C. This excellent insulating performance significantly reduces heat loss and energy consumption in high-temperature furnaces–.
High Purity: With carbon content reaching 99.5% to 99.9% and ash content as low as 0.1% to 0.5%, Rayon-based graphite felt minimizes the risk of contamination in sensitive processes such as semiconductor and photovoltaic manufacturing–.
Low Density and Lightweight: With bulk density ranging from 0.08 to 0.12 g/cm³, the material is exceptionally lightweight, reducing the overall weight of furnace components and simplifying handling and installation.
Excellent Flexibility: The soft, pliable nature of Rayon graphite felt allows it to be folded, cut with a knife, and shaped to fit complex furnace geometries–. This flexibility eliminates installation dead zones and ensures complete thermal coverage–.
High-Temperature Resistance: In inert or vacuum atmospheres, Rayon soft graphite felt can withstand temperatures of 2800°C to 3000°C, maintaining its structural integrity and insulation performance under extreme conditions–.
Chemical Stability: The material exhibits excellent corrosion resistance and non-melting properties, making it suitable for aggressive chemical environments–.
When compared to PAN-based graphite felt, Rayon-based felt offers superior thermal insulation and lower thermal conductivity, particularly at higher temperatures–. While PAN-based felt provides greater mechanical strength, Rayon-based felt excels in applications where thermal efficiency and purity are the primary concerns–.
4. Applications in the Photovoltaic Monocrystalline Silicon Industry
The photovoltaic industry – particularly monocrystalline silicon production – represents one of the most critical application areas for Rayon soft graphite felt–. In the Czochralski (CZ) process used to produce monocrystalline silicon ingots for solar cells, maintaining precise thermal conditions within the furnace is essential for crystal quality and production efficiency–.
Rayon soft graphite felt serves as the core thermal insulation material in the hot zone of monocrystalline silicon furnaces–. Its applications include:
Furnace Insulation: The felt lines the furnace walls and hot zone components, minimizing heat loss and ensuring uniform temperature distribution throughout the crystal growth process–. This thermal uniformity is critical for producing high-quality monocrystalline silicon with consistent electrical properties–.
Energy Efficiency: By reducing heat loss, Rayon soft graphite felt significantly lowers the energy consumption of monocrystalline silicon furnaces. In an industry where energy costs represent a substantial portion of production expenses, this efficiency translates directly into cost savings.
Purity Assurance: The high purity of Rayon-based graphite felt – with carbon content exceeding 99.9% and minimal ash content – prevents contamination of the silicon melt and the growing crystal–. Even trace impurities can degrade silicon quality and reduce solar cell efficiency.
Long Service Life: The material’s stability at high temperatures and resistance to thermal cycling ensure long operational life, reducing the frequency of furnace relining and maintenance downtime–.
Flexibility in Installation: The soft, conformable nature of the felt allows it to be easily installed around complex hot zone components, ensuring complete thermal coverage without gaps or dead zones–.
Beyond monocrystalline silicon production, Rayon soft graphite felt is also widely used in polycrystalline silicon furnaces, vacuum furnaces, induction furnaces, heat treatment furnaces, and various other high-temperature industrial equipment–.
5. Data sheet/ properties /low prices /2026
6. BEIJING CFCCARBON CO., LTD – Your Professional Manufacturing Partner
CFCCARBON CO., LTD, headquartered in Beijing’s Yizhuang Economic Development Zone, is a leading manufacturer of graphite felts, carbon composites, and high-temperature insulation materials. With decades of experience in the carbon materials industry, the company has established a strong reputation for quality, reliability, and technical expertise among clients in North America, Europe, Asia, and beyond.
Production Line Optimization – CFCCARBON has recently completed a comprehensive upgrade of its Rayon soft graphite felt production lines. Through process optimization, advanced equipment integration, and improved manufacturing efficiency, the company has achieved:
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Higher Product Quality: Enhanced quality control systems ensure consistent product specifications across every batch. The upgraded production process delivers Rayon soft graphite felt with tighter tolerances on thickness, density, and thermal conductivity – ensuring reliable performance in critical applications.
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Greater Product Stability: Improved process control minimizes batch-to-batch variation, giving customers confidence in the consistency and predictability of the material they receive.
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Lower Production Costs: Streamlined manufacturing operations and increased production efficiency have significantly reduced per-unit costs. These savings are passed directly to customers through competitive pricing that is substantially lower than many Western and Japanese competitors – without any compromise on quality or performance.
Comprehensive Product Range – CFCCARBON produces Rayon-based graphite felt in a wide range of specifications: thicknesses from 1.5 mm to 15 mm, widths up to 1400 mm, and lengths from 10 to 100 meters. The company also offers customized solutions to meet specific customer requirements, including purification, cutting to size, and surface treatments.
Quality Assurance – All products undergo rigorous inspection for density, thermal conductivity, carbon content, ash content, and mechanical strength. CFCCARBON’s ISO 9001-certified quality management system ensures that every shipment meets the highest international standards.
Reliable Delivery – With optimized logistics and production scheduling, CFCCARBON offers stable, rapid delivery times that help customers maintain uninterrupted production schedules.
Professional Service – The company’s experienced technical team provides expert guidance on material selection, application optimization, and custom design solutions. From initial inquiry to after-sales support, CFCCARBON is committed to delivering responsive, professional service that builds lasting partnerships.
7. Contact CFCCARBON Today
Whether you are a photovoltaic manufacturer seeking reliable thermal insulation for your monocrystalline silicon furnaces, or an industrial operator looking for cost-effective high-temperature solutions, CFCCARBON is ready to serve your needs.
CFC CARBON CO., LTD
Address: Yizhuang Economic Development Zone, Beijing 100176, China
Website: www.cfccarbon.com
Email: potter@cfccarbon.com
Marketing Center: +86-18910941489
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