Ceramic fiber boards are prepared by a wet process. The preparation process is usually as follows: mixing chopped or broken ceramic fiber cotton with binders, additives, fillers, etc. and adding water to prepare ceramic fiber slurry. The slurry is formed by vacuum filtration. The fiberboard body is then dried and sanded to make a ceramic fiber board. The fiberboard prepared by this process has the advantages of small volume density and low thermal conductivity, and is widely used in metallurgy, machinery, electric power and petrochemical industries.
The drying process has an important impact on the drying efficiency and product quality of ceramic fiber boards. At present, the drying processes for ceramic fiber boards include natural drying, gas strong convection drying, electric heating drying and microwave drying. Among them, gas strong convection drying is widely used due to its advantages of small equipment investment, good stability, and easy operation. However, the ceramic fiber board body has a high moisture content, about 50% to 60% (w), and it takes a long time to use strong gas convection drying. Microwave drying has high efficiency (approximately 3 to 5 times that of strong convection drying) and takes less time; however, its equipment is expensive and subsequent maintenance costs are high. Different drying processes need to be set up according to different products, which puts a lot of pressure on the operators. The overall quality requirements are also relatively high. Here are some key factors in how the performance of ceramic fiber boards is affected by the drying process:
Density: The drying process can affect the density of ceramic fiberboard. Insufficient drying or improper temperatures can result in voids or pores in the board, reducing density. Lower density may reduce the material's thermal insulation properties.
Structural stability: The drying process is critical to the structural stability of ceramic fiber panels. Improper drying processes can cause stress to accumulate within the board, making it susceptible to breakage or cracking at high temperatures.
Thermal expansion: The thermal expansion characteristics of ceramic fiber boards at high temperatures are also affected by the drying process. The drying process can affect the crystal structure and thermal expansion coefficient of the sheet, thereby affecting the dimensional stability of the material at high temperatures.
Mechanical properties: The drying process also affects the mechanical properties of ceramic fiber boards, such as strength and impact resistance. Improper drying processes may reduce the mechanical strength of the material, making it more susceptible to breakage.
Chemical stability: The drying process can affect the chemical stability of ceramic fiber sheets. If chemical treatments or coatings are present, the drying process may affect the effectiveness of these treatments.
Surface quality: The drying process can also affect the surface quality of ceramic fiber boards, such as flatness and finish. Smooth surfaces are often more suitable for certain applications, such as high-temperature furnaces.
In summary, the drying process has an important impact on the properties of ceramic fiber sheets, including density, structural stability, thermal expansion, mechanical properties, chemical stability and surface quality. Therefore, drying conditions need to be precisely controlled during the production process to ensure that the final product meets the requirements of the specific application.
