In today’s world, the rapid development of science and technology continues to drive the birth of new materials. Among them, silicon carbide fiber has become a shining star in the field of material science with its excellent high temperature resistance and mechanical strength. In this paper, we will discuss the characteristics, classification, application and preparation process of silicon carbide fiber to reveal the mystery of this amazing material.
Characteristics of silicon carbide fiber
Silicon carbide fiber, a kind of inorganic fiber made of silicone compounds as raw material through spinning, carbonization or vapor phase deposition process, belongs to the category of ceramic fiber. It has amazing physical and chemical properties:
- Heat resistance: the maximum use temperature can reach 1200℃, far beyond ordinary materials.
- Oxidation resistance: excellent performance at high temperatures, not easily oxidized.
- High strength: Strength ranges from 1960 to 4410MPa, several times that of ordinary steel.
- High modulus: The modulus reaches 176.4～294GPa, which ensures the rigidity of the material.
- Chemical stability: It is stable in a wide range of chemical environments.
These characteristics make silicon carbide fiber maintain its performance in extreme environments, making it an ideal material for aerospace, automotive manufacturing, sports equipment and other fields.
Classification of Silicon Carbide Fiber
Silicon carbide fibers are divided into two main categories: whiskers and continuous fibers.
- Whiskers: a single crystal form with a fine diameter, moderate length, powdery appearance, and extremely high strength and modulus.
- Continuous fibers: prepared by coating silicon carbide on core filaments or pure silicon carbide filaments, with good continuity and consistency.
Each of these two forms of fiber has its own strengths, and the right type is selected according to the application requirements.
Applications of Silicon Carbide Fibers
Silicon carbide fiber has a wide range of applications, mainly including:
- High-temperature resistant materials: such as heat shielding materials, high-temperature resistant conveyor belts, filtering materials for high-temperature gases or molten metals.
- Reinforcement materials: combined with carbon or glass fibers to reinforce metals and ceramics, such as aircraft brake pads, engine blades, etc.
- Sporting goods: use its light weight and high strength characteristics to make high performance sports equipment.
- High-temperature furnace materials: Short-cut fibers can be used to make high-temperature resistant furnace materials.
Preparation of Silicon Carbide Fiber
The preparation of silicon carbide filaments is a complex and delicate process:
- Synthesis of polysilanes: At high temperatures, the polysilanes undergo a thermal translocation reaction to form polycarbosilanes.
- Spinning: Polycarbosilanes are made into fibers by dry spinning or melt spinning techniques.
- Non-melting treatment: Treatment at lower temperatures prevents the fibers from melt bonding during subsequent carbonization.
- Carbonization: Heating to 1200-1500°C in vacuum or inert gas to form β-silicon carbide structure.
- Sizing treatment: Selection of suitable sizing agent, such as epoxy resin, according to the end use.
- Cluster winding: Cluster and wind the fibers for subsequent processing and application.
Conclusion
Silicon carbide fiber occupies an important position in the field of new materials with its excellent performance. With the continuous progress of science and technology, we have reason to believe that this material will play an important role in more areas to promote the development of human society. Whether in high-end applications in aerospace or ordinary products in daily life, silicon carbide fiber will continue to bring convenience and progress to mankind with its unique value.