Thermal-assisted cold sintering study of Al2O3 ceramics: Enabled with a soluble γ-Al2O3 intermediate phase

被引：16

作者：

Kang, Shenglin ^{[1
]}

Zhao, Xuetong ^{[1
]}

Guo, Jing ^{[2
]}

Liang, Jie ^{[1
]}

Sun, Jianjie ^{[1
]}

Yang, Yang ^{[1
]}

Yang, Lijun ^{[1
]}

Liao, Ruijin ^{[1
]}

Randall, Clive A. ^{[3
,4
]}

机构：

[1] Chongqing Univ, State Key Lab Power Transmission Equipment & Syst, Chongqing 400044, Peoples R China

[2] Xi An Jiao Tong Univ, State Key Lab Mech Behav Mat, Xian 710049, Peoples R China

[3] Penn State Univ, Mat Res Inst, University Pk, PA 16802 USA

[4] Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA

来源：

JOURNAL OF THE EUROPEAN CERAMIC SOCIETY | 2023年 / 43卷 / 02期

基金：

中国国家自然科学基金;

关键词：

Thermal -assisted cold sintering process; Phase transition; Hardness; Heat treatment; ALPHA-ALUMINA; MECHANICAL-PROPERTIES; FRACTURE-TOUGHNESS; MICROSTRUCTURAL EVOLUTION; SOL-GEL; ALPHA-AL2O3; COMPOSITES; TRANSFORMATION; DENSIFICATION; BOEHMITE;

D O I：

10.1016/j.jeurceramsoc.2022.10.039

中图分类号：

TQ174 [陶瓷工业]; TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Thermal-assisted cold sintering process (TA-CSP) has been applied to fabricate high dense alpha-Al2O3 ceramics with submicron grain sizes. The alpha-Al2O3 (80 wt%) and gamma-Al2O3 (20 wt%) powders are firstly mixed and then cold sintered at 300 degrees C to produce a green bulk with a relatively high density of -86.9 %, and then later a second heat treatment (800-1350 degrees C) is applied to finally fabricate (-98 % dense) alpha-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 gamma-Al2O3 to alpha-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 degrees C. Therefore, it is feasible to utilize TA-CSP to prepare alpha-Al2O3 ceramics with small grain sizes at low sintering temperatures.

引用

页码：478 / 485

页数：8