Effect of Temperature on the Synthesis of ZrO_2-mullite Powders in Molten Sodium Sulfate

摘要

ZrO_2-mullite compound powders were synthesized with zircon and aluminum sulfate in molten sodium sulfate. Na_2ZrSiO_5 was prepared as intermediate with zircon and sodium carbonate at 900℃ for 3h. Then the mixture of resultant Na_2ZrSiO_5 and aluminum sulfate was heated at different temperatures in molten sodium sulfate salt. The ZrO)2-Al_2O_3-SiO_2 compound powders were obtained after washing away the solvable salts. The results showed that the compound powders synthesized at 800℃ were tetragonal ZrO_2, SiO_2 and Al_2O_3; the powders synthesized at 1000℃ were monoclinal ZrO_2 and mullite. The mullite in compound powders became to decompose when the reaction temperature increased over 1100℃.