Three-dimensional organization of rare-earth atoms at grain boundaries in silicon nitride
Three-dimensional organization of rare-earth atoms at grain boundaries in silicon nitride
复制标题
氮化硅中稀土原子晶界的三维组织
DOI：
10.1063/1.2009067
复制
发表时间：
2005
影响因子：
4
通讯作者：
D. Cockayne
中科院分区：
文献类型：
--
作者：
G. Winkelman;C. Dwyer;T. Hudson;D. Nguyen;M. Döblinger;R. Satet;M. Hoffmann;D. Cockayne
稀土元素用于制备Si3N4组分，促进针状晶粒的生长，对提高韧性至关重要；显然，拉比鲁更有效。为了探索这种差异，我们使用像差校正高角环形暗场扫描透射电子显微镜和图像处理技术确定了含La和含lu的Si3N4中非晶态相中稀土原子的三维组织。证据提出了实质性的原子结构在名义上无定形体积。在这两种情况下，非晶相中的原子排列都符合端晶平面的周期性，但附着位置却有很大的不同。
Used in the preparation of Si3N4 components, rare-earth elements promote the growth of needlelike grains essential to elevated toughness; evidently, La is significantly more effective than Lu. To explore this difference, we determine the three-dimensional organization of rare-earth atoms in the amorphous phase near prismatic interfaces in La- and Lu-containing Si3N4 using aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and image processing. Evidence is presented for substantial atomic structure in notionally amorphous volumes. While the atomic arrangement in the amorphous phase conforms to the periodicity of the terminating crystal plane in both cases, the attachment sites are very different.