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以金属Al粉、单质Si粉、α-Al_2O_3微粉为主要原料,高温氮化反应制备β-Sialon陶瓷。通过在反应物中分别添加不同含量的Y_2O_3和TiO_2烧结剂,研究分析和对比了Y~(3+)和Ti~(4+)对β-Sialon陶瓷晶相组成、晶格常数、微观结构及烧结性能的影响。采用SEM及EDS对试样的微观形貌进行观察与分析,利用X’Pert Plus软件分析晶相的晶格常数,采用半定量法计算试样晶相组成。结果表明:Y_2O_3和TiO_2可显著降低高温氮化法制备β-Sialon陶瓷试样中β-Sialon相的生成温度。伴随着Y_2O_3和TiO_2的引入,Al_2O_3在Si3N4中的固溶度提高,β-Sialon晶相的生成量增加,晶格常数和晶胞体积增大,烧结性能得到改善。综合对比分析,Y_2O_3和TiO_2均对制备β-Sialon陶瓷具有良好的促烧结作用,用成本较低的TiO_2代替传统的稀土氧化物作为助烧结剂无压烧结制备β-Sialon陶瓷是可行的。
The β-Sialon ceramics were prepared by metal Al powder, elemental Si powder and α-Al_2O_3 fine powder with high temperature nitridation reaction. The effects of Y ~ (3+) and Ti ~ (4+) on the crystal phase composition, lattice constant, microstructure and microstructure of β-Sialon ceramics were studied by comparing with different content of Y_2O_3 and TiO_2 sintering agent. Effect of sintering performance. The microstructure of the sample was observed and analyzed by SEM and EDS. The lattice constants of the crystalline phase were analyzed by X’Pert Plus software. The phase composition of the sample was calculated by semi-quantitative method. The results show that the formation temperature of β-Sialon phase in β-Sialon ceramic samples prepared by high-temperature nitriding can be significantly reduced by Y_2O_3 and TiO_2. With the introduction of Y 2 O 3 and TiO 2, the solubility of Al 2 O 3 in Si 3 N 4 increases, the amount of β-Sialon phase increases, the lattice constant and unit cell volume increase, and the sintering properties improve. Comprehensive comparison and analysis, Y_2O_3 and TiO_2 both have a good sintering promoting effect on the preparation of β-Sialon ceramics. It is feasible to use low-cost TiO_2 instead of the traditional rare earth oxides as sintering aids to prepare β-Sialon ceramics by pressureless sintering.