Refractory fibers belong to non dense materials, which means that metal melts and slag are easily infiltrated into the fibers, leading to damage to the furnace lining. Therefore, refractory fibers are not suitable for areas that require direct contact with molten materials.

Low intensity:
Compared with dense refractory materials, the strength of refractory fiber products is lower. Special protective measures need to be taken to enhance the durability of parts that are frequently subjected to mechanical compression, collision, and friction.
Not resistant to erosion:
Refractory fiber products are more sensitive to the scouring effect of airflow. When used as furnace lining, the airflow velocity inside the furnace should be controlled within a certain range (generally less than 10m/s) to avoid damage caused by erosion.
The usage temperature is affected by the atmosphere:
The service life of refractory fibers is closely related to the atmosphere they are in. The operating temperature under reducing atmosphere and vacuum should be lower than that under oxidizing atmosphere. Specifically, the temperature should be 100-150 ℃ lower when used in a reducing atmosphere, and 250-300 ℃ lower when used in vacuum.

Application scenarios
High temperature insulation:
Refractory fibers are mainly used as insulation materials for high temperatures. Due to its excellent thermal insulation performance, it can effectively reduce heat transfer and improve the thermal efficiency of the furnace.
Parts that do not come into contact with high-speed airflow, molten metal, and slag:
Although refractory fibers are not suitable for direct contact with molten materials, they are still an ideal choice in high-temperature flame contact areas that do not come into contact with high-speed airflow, molten metal, and slag.
Sealing, sound-absorbing, and filtering materials:
Refractory fibers can also be used as sealing materials due to their flexibility and plasticity, which can effectively fill gaps and improve the sealing performance of furnaces. At the same time, it can also serve as a sound-absorbing and filtering material, playing an important role in specific situations.
Reinforcing materials for high-temperature composite materials:
When manufacturing high-temperature composite materials, refractory fibers can be used as reinforcement materials to improve the overall performance of the composite materials.
Temperature range for use
Glass refractory fiber: 1000-1300 ℃
Polycrystalline mullite fiber and polycrystalline alumina fiber: 1250-1500 ℃
Zirconia fiber: 1600 ℃
In summary, refractory fibers have a wide range of application prospects in the high-temperature industrial field, but reasonable selection and use need to be made based on their characteristics and application scenarios.