Single-Step Fabrication of Nanolamellar Structured Oxide Ceramic Coatings by Metal-Organic Chemical Vapor Deposition
Single-Step Fabrication of Nanolamellar Structured Oxide Ceramic Coatings by Metal-Organic Chemical Vapor Deposition
复制标题
金属有机化学气相沉积一步法制备纳米层状结构氧化物陶瓷涂层
DOI：
10.1166/jnn.2011.5081
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发表时间：
2011
影响因子：
--
通讯作者：
C.-P. Klages
中科院分区：
文献类型：
--
作者：
N. K. Eils;P. Mechnich;H. Keune;G. Wahl;C.-P. Klages
用MOCVD设备在实验室规模上制备了Y_2O_3-Al_2O_3-ZrO_2系统的氧化物陶瓷涂层。热壁反应器与不同的前体进料系统一起使用沿着。大多数实验是通过使用粉末闪蒸进行的，包括用于前体粉末输送的螺旋进料器。为了比较，通过使用带式闪蒸和从坩埚连续蒸发来制造另外的样品。在所有情况下使用氧气作为反应气体。由于Al（acac）3、Y（thd）3和Zr（thd）4在给定条件下具有相似的蒸发行为，因此将它们用作金属有机前驱体。涂层的化学计量从纯氧化铝的Y2 O3-Al 2 O3-ZrO 2系统中的复杂的三元组合物的变化。这两种类型的三元涂层通过使用闪蒸方法制备的沉积状态下显示出纳米片层的微观结构。在1200 °C下进行长达5天的热处理实验增强了通过使用粉末闪蒸沉积的涂层的层状特征。层状显微组织是由于在这种状态下交替的YSZ富集层和YAG富集层。然而，通过使用带式闪蒸制造的涂层显示出致密的YSZ和YAG的互穿网络热处理后，而不是在沉积状态下观察到的层状显微结构。
Oxide ceramic coatings in the system Y2O3–Al2O3–ZrO2 were fabricated in laboratory scale by using a MOCVD unit. A hot wall reactor was used along with different precursor feeding systems. Most experiments were carried out by using powder flash evaporation including a screw feeder for precursor powder delivery. For comparison, further samples were fabricated by using band flash evaporation and continuous evaporation from a crucible. Oxygen was used in all cases as reactant gas. Aluminium-tris-2,4-pentanedione (Al(acac)3), yttrium-tris-2,2,6,6-tetramethyl-3,5-heptanedione (Y(thd)3) and zirconium-tetrakis-2,2,6,6-tetramethyl-3,5-heptanedione (Zr(thd)4) were applied as metal-organic precursors because of their similar vaporization behaviour under the given conditions. The coating stoichiometry was varied from pure alumina to complex ternary compositions in the system Y2O3–Al2O3–ZrO2. Both kinds of ternary coatings fabricated by using flash evaporation methods show a nanolamellar microstructure in the as deposited state. Heat treating experiments at 1200 °C for up to 5 days enhance the lamellar character of the coating deposited by using powder flash evaporation. The lamellar microstructure is due to alternating YSZ enriched layers and YAG enriched layers in this state. However, the coating fabricated by using band flash evaporation shows a dense interpenetrating network of YSZ and YAG after heat treating instead of a lamellar microstructure observed in the as deposited state.