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研究了不同原子量的稀土元素对稀土Ｒ－α’－Ｓｉａｌｏｎ（Ｒ—Ｎｄ，Ｓｉｎ，Ｇｄ；Ｄｙ，Ｅｒ和Ｙｂ）致密化行为和形成特性的影响．样品分别以热压及无压烧结工艺制备．研究结果表明，样品达到完全致密化所需的热压温度随稀土元素原子量增加而减少，在１５５０℃热压保温１ｈ的Ｙｂ－α’－Ｓｉａｌｏｎ已完全致密，而样品中α’－Ｓｉａｌｏｎ相的含量随稀土元素原子量的增加而变大．比较了热压及无压烧结形成的Ｒ－α’－Ｓｉａｌｏｎ的反应过程，并讨论了少量β’－Ｓｉａｌｏｎ及黄长石与α’－Ｓｉａｌｏｎ同时存在的原因．ＴＥＭ照相显示了材料中非常窄的晶界．为进行对比，同时制备了Ｙ－α’－Ｓｉａｌｏｎ样品．
The effects of rare earth elements with different atomic weights on the densification behavior and formation characteristics of R-α’-Sialon (R-Nd, Sin, Gd; Dy, Er and Yb) Samples were hot-pressed and pressureless sintering process. The results show that the hot pressing temperature required for complete densification decreases with the increase of atomic weight of rare earth elements. The Yb-α’-Sialon hot-pressed at 1550 ℃ for 1 h has been completely densified, while the α’-Sialon phase The content increases with the atomic weight of rare earth elements. The reaction process of R-α’-Sialon formed by hot pressing and pressureless sintering was compared, and the reasons for the coexistence of a small amount of β’-Sialon and theα’-Sialon were also discussed. TEM photographs show very narrow grain boundaries in the material. For comparison, Y-α’-Sialon samples were also prepared.