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China has rich refractory raw material resources, kyanite is a positive development and utilization of important resources. In this thesis, kyanite as raw material to produce mullite - cordierite high temperature materials, and to explore the relationship between the composition, structure and properties of mullite - cordierite, aims to develop a high-performance refractory kiln furniture (such as bowl) material to be applied to the the actual ceramic industrial production. The papers to 50wt% kyanite amount of raw material, 5 wt% or so purple knots as combination of clay, mullite - cordierite were 7:3 and 3:7 matrix system with, then composite 50wt% Shandong flint as aggregate, a series of a plurality of formulations to test a plurality of the firing temperature. Seen through the study of the project: the use of natural raw materials kyanite synthetic performance mullite - cordierite composite refractories. Wherein of MgO (in order to burn the talc, magnesite introduced in the form) introduced to improve the firing performance of the sample, when the firing temperature is 1300 ° C and 1350 ℃ liquid phase sintering, the sintering shrinkage of greater than kyanite mullitization arising from volume expansion effect. By analysis of the microstructure of the sintered material, the formulation 1,2,3,5 reasons for the higher flexural strength is due to the relatively dense material microstructure in several formulations, uniform distribution of particles, uniform distribution of columnar mullite and reticular structure, which makes the fracture contains two forms of transgranular and intergranular, the flexural strength of the material; of formula 2,6,8 speaking, the point of view from the microstructure of materials fault transgranular fracture, the fracture surface is not smooth, conchoidal, which shows the development of the grain boundaries of the material is relatively good, and has high strength. When an external force, the crack propagation is not in the grain boundary, but passes through the interior of the grains causing fracture, so that the material has a higher strength. The experimental results show that: the powder particle gradation of kyanite production of natural raw materials is very important. In this experiment, the particle size distribution of raw materials, the experimental results appear quite different. In addition, in this paper, further analysis of the impact of feed additives and temperature on the performance of the material. Preliminary studies have shown that the additive effect: the right amount of additive (CaO, the TiO 2 Fe 2 the O 3 R 2 O) and the raw material, the main crystal phase to form a solid solution, so that the main crystal phase defect concentration increases, the particle diffusion speed, to promote a solid-phase hair and sintering conducted. Favorable to the formation of cordierite. But starting additive there is an optimal range, the additive content is too high will cause the glass phase content is increased, resulting in a decrease in thermal stability. Best control range of CaO lt; 2.0 wt% TiO 2 lt; 2.0 wt%, preferably do not exist Fe 2 O 3 try to control R 2 O amount.
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