As mentioned before, ceramic fiber module is different from other materials and is not applicable to the principle of thermal expansion and cold contraction. On the contrary, there will be a certain contraction when heated at high temperature. Let’s analyze it from a physical point of view.
The shrinkage of ceramic fiber during heating is a very important characteristic, which is directly related to crystallization and grain growth. At the temperature before crystallization, the refractory fiber does not shrink. When the temperature increases to the crystallization temperature, the fiber shrinks.
Crystallization indicates the beginning of shrinkage and represents the beginning of the so-called fiber crimping process. The curl or deformation of a single fiber is the mechanism leading to the shrinkage of fiber aggregates. Grain growth when the crystalline phase begins to precipitate, a very fine grain structure begins to form. This kind of grain grows with the extension of time and the increase of temperature.
As the grain grows, when its size approaches the diameter of a single fiber, the strength of a single fiber will become weaker. It will shrink continuously with the delay of time, which will reduce the effective length of the fiber and produce overall shrinkage after long-term use.
It should be noted that at 1200 ℃, the shrinkage of 1400 grade (high alumina content) ceramic fiber is greater than that of 1260 grade; At 1400 ℃, the contraction speed of 1400 level will be much lower than that of 1260 level.
Therefore, in practical application, we should not only consider the service temperature of the product, but also consider the shrinkage rate at a certain working temperature to comprehensively select materials, rather than blindly pursuing the high-temperature grade. For example, at the furnace temperature of 1000 ℃, the service effect and durability of 1260 high-purity fiber are higher than 1400 high aluminum fiber. In the high temperature environment of 1200 degrees, there is no doubt that the comprehensive effect of high aluminum type and low zirconium type is the best.
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Shandong redon high temperature materials Co., Ltd. has domestic high-end production equipment and reliable production technology, with an annual output of 1050 ceramic fiber series products, 1260 ceramic fiber series products, 1400 ceramic fiber series products and 1600 polycrystalline series products of more than 10000 tons. There are more than 30 kinds of products in different forms, such as cotton, blanket, felt, board, paper, various textiles, profiled products, modules, folding blocks, castables, spraying and so on, which can meet the heat insulation requirements of different situations in the high temperature field. Welcome to click the online service at the bottom right of the website or submit an online inquiry. We will contact you as soon as possible.