Highly transparent cubic γ-Al2O3 ceramic prepared by high-pressure sintering of home-made nanopowders. Issue 9 (August 2023)

• Record Type: Journal Article
• Authors: Chen, Xingtao; Guo, Wang; Wang, Haomin; Wu, Yiquan; Lu, Tiecheng
• Is Part Of: Journal of the European Ceramic Society. Volume 43:Issue 9(2023)
• Page Start: 4219
• Page End: 4225
• Publication Date: 2023-08
• Subjects: γ-Al2O3 -- Transparent ceramics -- Optical properties -- High-pressure sintering; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2023.03.003
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: Highly transparent gamma-aluminum oxide (γ-Al2 O3 ) ceramics were fabricated for the first time, by combining homogeneous precipitation and high-pressure sintering in the absence of exogenous dopants. The resulting cubic γ-Al2 O3 transparent ceramic material exhibits a promising replacement for single-crystal sapphire. The optimum optical properties are achieved in response to sintering at 5 GPa and a temperature of 300 °C and include maximum transmittance of 86% in the range of 0.6–1.2 µm which are properties that are comparable to those of single-crystal sapphire (∼86%). Vickers hardness (16 GPa) and compressive strength (350 MPa) in response to high-pressure sintering are also similar to those of a conventional sapphire single crystal. Meanwhile, the dielectric constant (9.46) is comparable to that of sapphire in the C-axis direction. These findings will facilitate further development of transparent Al2 O3 ceramics for use in a wider range of optical applications.