(1. 河北科技大学 材料科学与工程学院，石家庄 050018；
2. 河北科技大学 河北省材料近净成形技术重点实验室，石家庄 050018)
摘 要: 在CaO、Al2O3摩尔比为1.0、Na2O质量分数为12%和烧结温度为800~1350 ℃的条件下，研究Na2O-CaO- Al2O3物料的物相转变、晶体稳定性、微观形貌及其与Na2CO3溶液的反应活性。结果表明：Na2O掺杂将促进12CaO·7Al2O3向2Na2O·3CaO·5Al2O3的转化；Na+取代优先生成的12CaO·7Al2O3结构中Ca2+位置进一步转化成2Na2O·3CaO·5Al2O3；升高烧结温度有利于12CaO·7Al2O3向2Na2O·3CaO·5Al2O3的转化速率，同时也会增大Na2O的烧损，从而降低2Na2O·3CaO·5Al2O3的生成量；烧结温度为1350℃、时间为2.0 h时，Na2O-CaO-Al2O3物料的物相组成为12CaO·7Al2O3和2Na2O·3CaO·5Al2O3，Al2O3的溶出性能良好，约为98%。
关键字: 2Na2O·3CaO·5Al2O3；12CaO·7Al2O3；微观结构；晶体稳定性；氧化铝溶出性能
（1. School of Material Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China;
2. Hebei Key Laboratory of Material Near-Net Forming Technology, Hebei University of Science and Technology, Shijiazhuang 050018, China）
Abstract:The mineral transition, crystal stability, microstructure and reaction activity with sodium carbonate solution of Na2O-CaO-Al2O3 materials sintered at 800-1350 ℃ were studied when the molar ratio of CaO to Al2O3 is 1.0 and the mass fraction of Na2O is 12%. The results show that sodium doping can promote 12CaO·7Al2O3 transform into 2Na2O·3CaO·5Al2O3. Na+ can replace the Ca2+ lattice position of priority generated 12CaO·7Al2O3 to form 2Na2O·3CaO·5Al2O3. Increasing sintering temperature can accelerate the conversion process from 12CaO·7Al2O3 to 2Na2O·3CaO·5Al2O3, but it also can increase Na2O loss, and then decrease 2Na2O·3CaO·5Al2O3 production. The mineral compositions of Na2O-CaO-Al2O3 materials are 12CaO·7Al2O3 and 2Na2O·3CaO·5Al2O3, which also have good alumina leaching property of 98%.
Key words: 2Na2O·3CaO·5Al2O3; 12CaO·7Al2O3; microstructure; crystal stability; alumina leaching property
