Structure Composition Of Refractory Materials
Date:2016-01-19 10:29 From:Zhengzhou Sunrise Refractory Author:admin
According to the properties of the constituent phases in the refractory materials, the proportion of the composition and the influence on the properties of the materials, refractory material contains main crystal phase, secondary crystal phase and matrix.
1. Main crystal phase
Main crystal phase refers to the main body of material structure with high melting point, and it has a dominant effect on the properties of the material. The property, quantity, distribution and combining state directly determine the property of products. Many refractory products are named after their main crystal phase, such as mullite bricks, corundum block, periclase brick, spinel brick, silicon carbide and so on.
2. Secondary crystal phase
Secondary crystal phase is also called the second crystal phase or second solid phase which refers to the coexistence of the main phase and liquid phase at high temperature in refractory materials, generally the number of them is small and the effect of the high temperature properties of the material is smaller than that of the primary crystal phase. For example, the main crystal phase of magnesia chrome brick, magnesia alumina brick, magnesia silica brick and magnesia calcium brick is periclase, however, their secondary crystal phase respectively is chrome spinel, spinel, forsterite and two calcium silicate. Secondary crystal phase of refractory has influence on the structure of refractory, especially on the direct combination of high melting crystalline phases, which can resistance the high temperature. Many refractory bricks named after mineral is compound named after its main crystal phase and secondary crystalline phase, such as mullite corundum block and corundum mullite brick.
3. Matrix
Matrix exists between the large crystal gap of refractory or that part of the material is embedded in it, and can also be considered as a filler or cement between large crystals. Matrix can be composed of fine crystal, glass phase or complex of both. The matrix is the phase other than the main and secondary phases, and it always contains all or most of the impurities other than the principal component. So these phases are easy to form liquid phase which makes the products easy to be sintered, but it is not conducive to the combination of the main crystal and damage the property of high temperature. When the matrix is low in the liquid phase at high temperature, the viscosity of the liquid is low and the quantity of the liquid phase is more, the production and the properties of the refractory products are controlled by the matrix. In order to improve the quality of refractory materials, it is necessary to improve the quality of matrix of refractory materials, reduce the number of matrix, and improve the distribution of matrix.
1. Main crystal phase
Main crystal phase refers to the main body of material structure with high melting point, and it has a dominant effect on the properties of the material. The property, quantity, distribution and combining state directly determine the property of products. Many refractory products are named after their main crystal phase, such as mullite bricks, corundum block, periclase brick, spinel brick, silicon carbide and so on.
2. Secondary crystal phase
Secondary crystal phase is also called the second crystal phase or second solid phase which refers to the coexistence of the main phase and liquid phase at high temperature in refractory materials, generally the number of them is small and the effect of the high temperature properties of the material is smaller than that of the primary crystal phase. For example, the main crystal phase of magnesia chrome brick, magnesia alumina brick, magnesia silica brick and magnesia calcium brick is periclase, however, their secondary crystal phase respectively is chrome spinel, spinel, forsterite and two calcium silicate. Secondary crystal phase of refractory has influence on the structure of refractory, especially on the direct combination of high melting crystalline phases, which can resistance the high temperature. Many refractory bricks named after mineral is compound named after its main crystal phase and secondary crystalline phase, such as mullite corundum block and corundum mullite brick.
3. Matrix
Matrix exists between the large crystal gap of refractory or that part of the material is embedded in it, and can also be considered as a filler or cement between large crystals. Matrix can be composed of fine crystal, glass phase or complex of both. The matrix is the phase other than the main and secondary phases, and it always contains all or most of the impurities other than the principal component. So these phases are easy to form liquid phase which makes the products easy to be sintered, but it is not conducive to the combination of the main crystal and damage the property of high temperature. When the matrix is low in the liquid phase at high temperature, the viscosity of the liquid is low and the quantity of the liquid phase is more, the production and the properties of the refractory products are controlled by the matrix. In order to improve the quality of refractory materials, it is necessary to improve the quality of matrix of refractory materials, reduce the number of matrix, and improve the distribution of matrix.