Preparation of alumina ceramic template by the molten salt method

ABSTRACT

Single-crystal alpha alumina (α-Al₂O₃) platelets were synthesised with aluminium sulphate in the study. Moreover, the effects of the heating temperature, holding time, and different power mixtures of γ-Al₂O₃ and sodium sulphate (Na₂SO₄) on the morphology of as-prepared α-Al₂O₃ platelets were explored. The crystalline phase evolution and morphology of the samples were characterised by X-ray diffraction and scanning electron microscopy. According to the further analysis results, most of α-Al₂O₃ platelets were hexagonal particles. After the power mixture of γ-Al₂O₃ and Na₂SO₄ (1:2) was heated at 1200°C for 1 h, the platelet size became relatively uniform with an average diameter of 3–5 μm and a thickness of 50–100 nm. This method is an easily controllable, simple, and green method to produce high-quality α-Al₂O₃ platelets.

KEYWORDS:

• Alpha alumina
• platelet
• phase transformation
• molten salt synthesis

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Fundamental Research Funds for the Central Universities (Grant no. 2652017399) and the National Natural Science Foundation of China (NNSFC Grant no. U1607113).