TY - JOUR
T1 - Thermal-assisted cold sintering study of Al2O3 ceramics
T2 - Enabled with a soluble γ-Al2O3 intermediate phase
AU - Kang, Shenglin
AU - Zhao, Xuetong
AU - Guo, Jing
AU - Liang, Jie
AU - Sun, Jianjie
AU - Yang, Yang
AU - Yang, Lijun
AU - Liao, Ruijin
AU - Randall, Clive A.
N1 - Funding Information:
This work was supported by the Fund of the National Natural Science Foundation of China (Grant no. 51877016 ), and the Fok Ying-Tong Education Foundation , China (No. 171050 ). Authors thank Sinoma Institute of Materials Research (Guang Zhou, China) Co., Ltd. for TEM test.
Funding Information:
This work was supported by the Fund of the National Natural Science Foundation of China (Grant no. 51877016), and the Fok Ying-Tong Education Foundation, China (No. 171050). Authors thank Sinoma Institute of Materials Research (Guang Zhou, China) Co. Ltd. for TEM test.
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2023/2
Y1 - 2023/2
N2 - Thermal-assisted cold sintering process (TA-CSP) has been applied to fabricate high dense α-Al2O3 ceramics with submicron grain sizes. The α-Al2O3 (80 wt%) and γ-Al2O3 (20 wt%) powders are firstly mixed and then cold sintered at 300 °C to produce a green bulk with a relatively high density of ∼ 86.9 %, and then later a second heat treatment (800–1350 °C) is applied to finally fabricate (∼ 98 % dense) α-Al2O3 ceramics with grain sizes of 720 nm. A microstructural analysis with XRD and TEM suggests that the TA-CSP samples not only complete the final densification but also drive a phase transition of γ-Al2O3 to α-Al2O3. To put into perspective the Hardness and Young's modulus of TA-CSP samples reach ∼ 14 GPa and ∼ 335 GPa, respectively, which is comparable to conventional sintered samples processed at higher temperatures of 1500–1700 °C. Therefore, it is feasible to utilize TA-CSP to prepare α-Al2O3 ceramics with small grain sizes at low sintering temperatures.
AB - Thermal-assisted cold sintering process (TA-CSP) has been applied to fabricate high dense α-Al2O3 ceramics with submicron grain sizes. The α-Al2O3 (80 wt%) and γ-Al2O3 (20 wt%) powders are firstly mixed and then cold sintered at 300 °C to produce a green bulk with a relatively high density of ∼ 86.9 %, and then later a second heat treatment (800–1350 °C) is applied to finally fabricate (∼ 98 % dense) α-Al2O3 ceramics with grain sizes of 720 nm. A microstructural analysis with XRD and TEM suggests that the TA-CSP samples not only complete the final densification but also drive a phase transition of γ-Al2O3 to α-Al2O3. To put into perspective the Hardness and Young's modulus of TA-CSP samples reach ∼ 14 GPa and ∼ 335 GPa, respectively, which is comparable to conventional sintered samples processed at higher temperatures of 1500–1700 °C. Therefore, it is feasible to utilize TA-CSP to prepare α-Al2O3 ceramics with small grain sizes at low sintering temperatures.
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U2 - 10.1016/j.jeurceramsoc.2022.10.039
DO - 10.1016/j.jeurceramsoc.2022.10.039
M3 - Article
AN - SCOPUS:85140070266
SN - 0955-2219
VL - 43
SP - 478
EP - 485
JO - Journal of the European Ceramic Society
JF - Journal of the European Ceramic Society
IS - 2
ER -