| Calcium-hexaluminate materials have many excellent performances, which could be used as a new type of light high temperature refractory. Firstly, Using industrial aluminum hydroxide, industrial alumina, calcium hydroxide, calcium oxide and calcium carbonate as raw materials, cement as bonding agent, the synthesis of Calcium-hexaluminate was studied in the paper. The effect of synthesis temperature, holding time, mixing crushed time on synthesis of calcium-hexaluminate are investigated. And on the basic of the previous experiments, the lightweight calcium hexaluminate refractories were prepared by the foaming way. The influences of different foaming agents and adding agents on properties of lightweight CA6 refractory were studied.The results showed that CA6 could be observed from 1200℃, and a lot of CA6 crystals presented at 1400℃. Comparing with industrial aluminum hydroxide, using industrial alumina as raw material, it was better to synthesize CA6. The crystals of CA6 are the typical platelet shape. Discreasing the particle size and prolonging the sorking time were favor to the morphology development of CA6 crystal grains.Many factors influenced the properties of lightweight CA6 materials. Firstly, the types of foaming agents remarkably affect the performances of materials, and the SDBS is suitble, because of it's the better foaming performance and lots of air bubbles. Secondly, the stability of air bubble was markedly improved by adding the dextrin. And the water content and mixing time also affect the properties of lightweight CA6. When cement content was increased and activeα-Al2O3 was added, the crushing strength of the material increases obviously.
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