Surface Crystallization of a MgO/Y(2)O(3)/SiO(2)/Al(2)O(3)/ZrO(2) Glass: Growth of an Oriented β-Y(2)Si(2)O(7) Layer and Epitaxial ZrO(2).
Surface Crystallization of a MgO/Y(2)O(3)/SiO(2)/Al(2)O(3)/ZrO(2) Glass: Growth of an Oriented β-Y(2)Si(2)O(7) Layer and Epitaxial ZrO(2).
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DOI：
10.1038/srep44144
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发表时间：
2017-03-10
影响因子：
4.6
通讯作者：
Rüssel C
中科院分区：
文献类型：
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作者：
Wisniewski W;Seidel S;Patzig C;Rüssel C
使用 X 射线衍射 (XRD)、扫描电子显微镜 (SEM)（包括电子背散射衍射 (EBSD)）和（扫描）透射电子显微镜 [(S)TEM]（包括能量色散 X 射线光谱法 (EDXS)）研究成分为 54.7 SiO2·10.9 Al2O3·15.0 MgO·3.4 ZrO2·16.0 Y2O3 的玻璃的结晶行为。该玻璃显示了成分为 Y2Si2O7 (YS) 的四种不同硅酸钇的唯一表面结晶。 α-、β-、δ-和 ε-YS 在表面几乎同时但独立的成核，随后生长到本体中，其中 ε-YS 很快占据了第一结晶层。 Mg 在生长前沿的积累可能会引发 β-YS 的二次成核，β-YS 会形成一层薄而致密的层，然后分裂成占据剩余体积的细晶粒晶体的高度取向层。 YS 生长结构之间的残余玻璃允许在冷却过程中结晶二氧化二长石、钇稳定 ZrO2 (Y-ZrO2) 以及很可能的 μ-堇青石。因此，这种玻璃基本上显示出与其他含有较少 Y2O3 的镁钇铝硅酸盐玻璃中观察到的相反的结晶顺序。 Y-ZrO2 和 ε-YS 之间存在外延关系，且 YS 相中存在多重孪晶关系。
The crystallization behavior of a glass with the composition 54.7 SiO2·10.9 Al2O3·15.0 MgO·3.4 ZrO2·16.0 Y2O3 is studied using X-ray diffraction (XRD), scanning electron microscopy (SEM) including electron backscatter diffraction (EBSD) and (scanning) transmission electron microscopy [(S)TEM] including energy-dispersive X-ray spectrometry (EDXS). This glass shows the sole surface crystallization of four different yttrium silicates of the composition Y2Si2O7 (YS). The almost simultaneous but independent nucleation of α-, β-, δ-, and ε-YS at the surface is followed by growth into the bulk, where ε-YS quickly dominates a first crystallized layer. An accumulation of Mg at the growth front probably triggers a secondary nucleation of β-YS, which forms a thin compact layer before fragmenting into a highly oriented layer of fine grained crystals occupying the remaining bulk. The residual glass between the YS growth structures allows the crystallization of indialite, yttrium stabilized ZrO2 (Y-ZrO2) and very probably μ-cordierite during cooling. Hence, this glass basically shows the inverted order of crystallization observed in other magnesium yttrium alumosilicate glasses containing less Y2O3. An epitaxial relationship between Y-ZrO2 and ε-YS is proven and multiple twinning relationships occur in the YS phases.