Ceramic fiber board is suitable for high-temperature fields that require rigid strength of the product, but sometimes it will turn yellow, which has a certain impact on our use. It not only affects the aesthetics, but also its use effect. So what are the reasons for its yellowing?
1. High temperature oxidation and crystal phase transformation
When exposed to high temperature for a long time, the impurities in the ceramic fiber are prone to oxidation reaction, generating yellow-brown products. At the same time, the amorphous fiber gradually crystallizes, and the change of internal structure also causes the color to turn yellow.
2.Carbonization and chemical corrosion of pollutants
If there is oil, dust or organic residue on the surface of the ceramic fiber board, it will form yellow scorch spots after carbonization at high temperature. In addition, acidic or alkaline gases may corrode the aluminum oxide or silicon dioxide components in the fiber to generate colored compounds such as sulfates.
3.Defects in materials and workmanship
Insufficient raw material purity or improper sintering process may result in unreacted oxides remaining inside the board, which will appear unevenly yellow when leaving the factory. Storage in a humid environment may also trigger a hydrolysis reaction, resulting in color change.
Countermeasures
To effectively solve the yellowing problem, Haixin Refractory launched a high-purity zirconium-containing ceramic fiber board, which uses ultra-low impurity raw materials and advanced crystal phase stabilization technology to significantly delay high-temperature oxidation and crystallization processes. At the same time, for corrosive environments, the company developed an acid- and alkali-resistant coated fiberboard that blocks gas and moisture erosion through surface densification treatment, greatly extending its service life. The product strictly follows ISO high-temperature stability tests to ensure that it maintains a white appearance and high strength even after long-term use at 1200°C.