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用热压制备了原始组成为 (Ca ,Nd) xSi1 2 - 3nAl3nOnN1 6 -n(x =1.0 ) [其中x =2n/v ,v为 (Ca+Nd)的价态 ] ,不同Ca∶Nd置换比例的复合掺杂 (Ca +Nd)α -sialon .藉助XRD和SEM研究了相形成规律和显微结构 .结果表明 :复合掺杂系统的致密化优于单一掺杂Ndα -sialon ;其在 175 0℃热压后的相组成包括α -sialon、黄长石固溶体和AlN多型体 .随设计组成中Ca/Nd摩尔比的增加 ,α -sialon含量升高 ,α -sialon晶胞也变大 .材料的显微结构中同时存在等轴状和长颗粒的α -sialon晶粒形貌 .EDS分析结果表明 :Ca大多进入α -sialon晶格 ,而Nd主要构成晶界相 .
(Ca, Nd) xSi1 2 - 3nAl3nOnN1 6 -n (x = 1.0) [where x = 2n / v, where v is the valence of (Ca + Nd)] was prepared by hot pressing with different Ca: Nd substitutions (Ca + Nd) α -sialon. The phase formation and microstructure were investigated by means of XRD and SEM. The results show that the densification of the composite doping system is better than that of single-doped Ndα-sialon; The phase composition after hot pressing at 0 ℃ includes α -sialon, yellow feldspar solid solution and AlN polytype.With the increase of Ca / Nd molar ratio in the designed composition, α -sialon content increases and α -sialon unit cell becomes larger. The α -sialon grain morphology of the equiaxed and long grains exists simultaneously in the microstructure.The results of EDS analysis show that Ca mostly enters the α -sialon lattice, whereas Nd mainly forms the grain boundary phase.