Due to factors such as fiber crystallization, grain growth, crystal phase transformation, and impurities' effects on crystallization, as well as the sintering and high-temperature creep at fiber contact points, ceramic fibers may shrink, lose elasticity, become brittle, and even sinter, losing their fibrous structure. Therefore, various types of ceramic fibers have a maximum service temperature, which is internationally classified into four grades: 1000℃, 1260℃, 1400℃, and 1600℃.

Ceramic fibers exhibit excellent thermal shock resistance, attributed to their aggregate structure (entangled fibers with diameters between 2-5μm and a porosity greater than 90%), which makes them soft, elastic, and capable of free elongation in all directions.

Ceramic fibers have excellent chemical stability in oxidizing and neutral atmospheres. However, their chemical stability is poor in reducing atmospheres, vacuums, or environments containing sulfates, fluorides, or alkaline metals.

Ceramic fiber aggregates are porous materials that can be used as sound-absorbing materials. Ceramic fiber products with low bulk density have good sound absorption for high-frequency waves but the opposite for low-frequency waves.

Ceramic fibers possess excellent electrical insulation properties, which decrease with rising temperatures. However, they still maintain a high dielectric constant and low dielectric loss at elevated temperatures.

Ceramic fiber aggregates are commonly used as high-temperature resistant materials. The introduction of non-woven needling technology in the production of secondary ceramic fiber products has improved the wind erosion resistance of ceramic fiber blankets to 20m/s.

When used as sealing or padding materials for high-temperature gases, ceramic fibers should have a certain degree of elasticity and air permeability resistance. As the temperature exceeds 400℃, they will experience some creep, causing a gradual decrease in the rebound resilience of fiber products.