Influence of high-energy ball milling and additives on the formation of sphere-like α-Al2O3 powder by high-temperature calcination

• Published in: Zeitschrift für Naturforschung. B, A journal of chemical sciences Vol. 73; no. 8; pp. 589 - 596
• Main Authors: Li, Sai, Zhu, Lingling, Liu, Luoqiang, Chen, Liugang, Li, Hongxia, Sun, Chunhui
• Format: Journal Article
• Language: English
• Published: De Gruyter 28.08.2018
• Subjects: additive; high-energy ball milling; industrial Al(OH); NH; spherical-like α-Al
• ISSN: 0932-0776; 1865-7117
• DOI: 10.1515/znb-2018-0080

In comparison with the typically worm-like α-Al powders formed from an unground Al(OH) precursor calcined at 1450°C, spherical α-Al powders with ~1 μm in size were prepared by the calcination of a ground Al(OH) precursor with 5 wt.% [NH BF under the same calcination conditions. The influence of a high-energy ball milling pretreatment as well as of the additives on the morphological evolution of α-Al powders was studied using the commercial precursor Al(OH) as raw material. The results indicate that the morphology of α-Al powders is closely related to the morphology of the Al(OH) precursor and to the introduction of different additives. The refinement of the Al(OH) precursor in aggregate size and of the primary crystal size by high-energy ball milling has effectively suppressed the neck growth of α-Al grains. In contrast to the findings made previously with the introduction of 5 wt.% [NH Cl , the morphology of the α-Al particles could be significantly improved from a ground Al(OH) precursor with the addition of 5 wt.% [NH BF , which resulted in the formation of spherical α-Al powders with 1 μm size at 1450°C.