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选用Ｓｉ３Ｎ４、ＡｌＮ、Ａｌ２Ｏ３和Ｓｍ２Ｏ３（或Ｎｄ２Ｏ３）粉末为原料，在１８００～１９５０℃的温度范围内，１．０～３．０ＭＰａ氮气压力下烧结（ＧＰＳ），制备了性能优良的Ｒｅ－α／β－Ｓｉａｌｏｎ（Ｒｅ＝Ｎｄ，Ｓｍ）陶瓷材料；利用ＸＲＤ、ＥＤＳ、ＴＥＭ和ＥＲＥＭ手段研究了材料的相组成、显微结构特性及其与性能的关系。结果表明，其主晶相为长柱状的β－Ｓｉａｌｏｎ和近似等轴的Ｒｅ－α－Ｓｉａｌｏｎ，晶界由少量的结晶相以及微量的玻璃相构成：长柱状的β－Ｓｉａｌｏｎ有利于提高材料的抗弯强度和断裂韧性。实验发现，以Ｓｍ２Ｏ３作为稳定剂比Ｎｄ２Ｏ３更容易形成α－Ｓｉａｌｏｎ。
Si3N4, AlN, Al2O3 and Sm2O3 (or Nd2O3) powders were used as raw materials and sintered at a temperature of 1800 ~ 1950 ℃ under nitrogen pressure of 1.0 ~ 3.0MPa to prepare the Re-α / β-Sialon (Re = Nd, Sm) ceramics. The phase composition, microstructural properties and their relationship with the properties of the materials were investigated by XRD, EDS, TEM and EREM. The results show that the main phase is β-Sialon with long columnar shape and Re-α-Sialon with approximate equiaxed phase. The grain boundary consists of a small amount of crystalline phase and a trace amount of glass phase. The long columnar β-Sialon promotes the increase of Flexural strength and fracture toughness. The experiment found that Sm2O3 as a stabilizer is easier to form α-Sialon than Nd2O3.