The zirconium-containing ceramic fiber blanket and the chromium-containing ceramic fiber blanket belong to the high-temperature oxide (ZrO2, Cr2O3) added to the aluminum silicate synthetic powder, which is beneficial to increase the viscosity of the glass phase and can effectively resist the glassy aluminum silicate fiber. Crystallization and grain growth at high temperatures, delaying the sintering of the fiber interlacing contact, thereby increasing the fiber’s resistance to high temperature shrinkage and fiber use temperature.
However, the zirconium-containing ceramic fiber blanket is superior to the chromium-containing ceramic fiber blanket in terms of production technology difficulty and performance.
The main differences between zirconium-containing ceramic fiber blankets and chromium-containing ceramic fiber blankets are as follows:
1. The eutectic and melting temperature of the raw material containing zirconium fiber is low, the energy consumption is small, the ZrO2 content in the fiber is generally 15%-17%, and the higher is up to 24%, the fiber formation is easy, the fiber is slender and the strength is high.
However, the chromium-containing synthetic material has no low eutectic point, the content of Cr2O3 in the fiber should not exceed 5%, and the lower melting temperature of the raw material for the production of chromium-containing aluminum silicate fiber is about 1800 ° C, which makes the melting of the raw material difficult, the power consumption is large, and the fiber is difficult. Large, the produced fibers are short and thin, and the fiber strength is poor.
Second, the chrome-containing ceramic fiber blanket has large shrinkage of the heating wire during use, and the high-temperature volume stability is poor. At the same time, the Cr2O3 in the fiber is easily volatilized at a high temperature, and the hexavalent chromium compound having a carcinogenic effect, such as CrO3, is caused to cause environmental pollution. Harm to human health.
Zirconium-containing fiber has excellent performance. The use of zirconium-containing ceramic fiber blanket at the classification temperature is much better than that of chrome-containing ceramic fiber blanket. ZrO2 added to the fiber has good high temperature stability and can be used at high temperatures. Volatile and environmental pollution problems.
Under the same temperature conditions, the insulation effect of the chrome-containing fiber blanket and the zirconium-containing fiber blanket is basically the same. The shrinkage of the chrome-containing blanket at 1400 ° C or less is larger than that of the zirconium-containing fiber blanket.
The application technology of ceramic fiber blankets stipulates that all types of fibers should be used below their classification temperature. Therefore, under the long-term use temperature conditions, the high-temperature volume stability of the zirconium-containing fiber blanket (evaluated by the line shrinkage index) is superior to that of the chrome-containing fiber blanket.