| 片状α-Al2O3颗粒粉体的制备 |
Alternative Title | Synthesis of plate-like single-phase α -Al2O3 particles
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| 李素强 |
Thesis Advisor | 李建功
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| 2009-06-01
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Degree Grantor | 兰州大学
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Place of Conferral | 兰州
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Degree Name | 硕士
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Keyword | 片状α-Al2O3
机械球磨
硫酸钾
相变
α-Al2O3 晶种
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Abstract | 片状α-Al2<下标!>O3<下标!>粉体材料由于其独特的结构和优异的性能被广泛应用到颜料、化妆品、汽车漆料、耐火材料、增韧陶瓷等各个领域。本文介绍了一种制备片状氧化铝粉末的新方法,即球磨采用沉淀法制备的拜耳石与硫酸钾混合粉末,再将球磨过的混合粉末在900°C下煅烧2h,得到了平均直径为700nm的片状α-Al2<下标!>O3<下标!>颗粒。分析了球磨后拜耳石的相变过程以及球磨参数对最终产品的结构和形貌的影响,以期在制备α-Al2<下标!>O3<下标!>片状颗粒的过程中来对其形貌和尺寸实现人为控制。
研究表明机械球磨后的拜耳石的相变过程为α-Al(OH)3<下标!>→γ-AlOOH → γ-Al2<下标!>O3<下标!> → α-Al2<下标!>O3<下标!>。添加硫酸钾与晶种对拜耳石的相变过程的转变顺序没有影响,但降低了 γ-Al2<下标!>O3<下标!> → α-Al2<下标!>O3<下标!>过程中的转变温度,并且α-Al2<下标!>O3<下标!>的相变完成温度降低了200°C。
球磨转速和球磨时间显著的影响α-Al2<下标!>O3<下标!>片状颗粒的晶体结构和形貌。球磨转速越高、球磨时间越长,相同煅烧条件下所得α-Al2<下标!>O3<下标!>片状颗粒的纯度越高,所得α-Al2<下标!>O3<下标!>片状颗粒的平均直径越小。 |
Other Abstract | Plate-like α-Al2<下标!>O3<下标!> have been widely used in the fields of pigment, cosmetic, vehicle paint, refractory, and toughness ceramic because of its especial structure and excellent properties. In the paper, a new method to prepare plate-like α-Al2<下标!>O3<下标!> is introduced. Plate-like single-phase α-Al2<下标!>O3<下标!> particles were successfully synthesized by calcining the ball-milled mixture of bayerite and K2<下标!>SO4<下标!> at 900°C for 2h. The average diameter of pate-like α-Al2<下标!>O3<下标!> particles is around 700 nm. The phase transition sequence of milled bayerite and the influence of the ball milling and K2<下标!>SO4<下标!> additive on the structure and morphology of the product were studied in the paper to realize artificial control of plate-like α-Al2<下标!>O3<下标!> particle size and shape during the preparation process.
It was found that the milled bayerite undergoes a series of phase transformations via the α-Al(OH)3<下标!> → γ-AlOOH → γ-Al2<下标!>O3<下标!> → α-Al2<下标!>O3<下标!> path. The addition of K2<下标!>SO4<下标!> and α-Al2<下标!>O3<下标!> seeding to the bayerite powder does not affect the sequence of the phase transformation of bayerite. However, the completion temperatures of the transformation to α-Al2<下标!>O3<下标!> in the milled bayerite with K2<下标!>SO4<下标!> additive and α-Al2<下标!>O3<下标!> seeding are about 200°C lower than that without K2<下标!>SO4<下标!> additive and α-Al2<下标!>O3<下标!> seeding.
The influence of the rotation speed of the mill and milling time on the structure and morphology of the product were significant. It was found that milling at a high speed and for a longer time can prepare plate-like α-Al2<下标!>O3<下标!> particles with better purity and smaller average diameter. |
URL | 查看原文
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Language | 中文
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Document Type | 学位论文
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Identifier | https://ir.lzu.edu.cn/handle/262010/229498
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Collection | 物理科学与技术学院
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Recommended Citation GB/T 7714 |
李素强. 片状α-Al2O3颗粒粉体的制备[D]. 兰州. 兰州大学,2009.
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