The types and number of mineral phases in mullite bricks are basically the same, but the crystal size, the distribution state between the crystals and the matrix are quite different, that is, the microstructure is very different, so the performance is also greatly different. The microstructure of mullite brick is very important to the influence of mullite brick performance.
If the main crystal phase is combined by the silicate glass phase, according to the distribution state of the main crystal phase and the matrix, the microstructure can be divided into two categories: one is that the number of liquid phases is large or the main crystal phase is well wetted , The main crystalline phase is surrounded by the glass phase, forming a continuous matrix, the main crystalline phase is discontinuous; the other is that the number of liquid phases is small or the main crystalline phase is poorly wetted, the main crystalline phase is not completely surrounded by the matrix, and It is the main crystal phase that isolates the matrix. The main crystal phase and the main crystal phase have contact points, forming a continuous main crystal phase and a discontinuous matrix structure. Obviously, the formation of the main crystalline phase is continuous, and the matrix discontinuous structure can give full play to the high-temperature performance of the main crystalline phase, which is conducive to the improvement of product quality.
