Articles
  • Microwave sintering and mechanical properties of La2O3/Nb2O5 toughened Al2O3 ceramics

  • Jin Liu, Bingliang Liang*, Yunlong Ai, Jianjun Zhang, Fei He, Wen He and Zhiyong Liu

  • School of Materials Science and Engineering, Nanchang Hangkong University, No.696, South Fenghe Avenue, Nanchang 330063, Jiangxi Province, P.R. China

  • This article is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

To improve the toughness of Al2O3 ceramic, xLa2O3/10Nb2O5-(90–x)Al2O3 (x = 2.5-15.0 vol.%) composite ceramics were synthesized via microwave-sintering. The influences of sintering temperature (Ts) and La2O3 content on phase composition and mechanical property of xLa2O3/10Nb2O5-(90–x)Al2O3 composite ceramics were studied. It is shown in the results that the Ts of La2O3/Nb2O5 doped Al2O3 ceramic was 150 oC lower than that of Al2O3 ceramic. With the increase of x, La0.33NbO3, LaNbO4 and LaAl11O18 were formed successively. LaNbO4, columnar-Al2O3 grains and LaAl11O18 with plate-like shape were generated in-situ during the sintering period. Compared to Al2O3 ceramic, the fracture toughness of xLa2O3/10Nb2O5-(90–x)Al2O3 ceramics were at least 70% higher when 5.0 ≤ x ≤ 12.5. 7.5La2O3/10Nb2O5-82.5Al2O3 ceramic exhibited superior mechanical property: Hv = 12.0 GPa, KIC = 6.2 MPa·m1/2 (1,500 oC, 30 min)


Keywords: Al2O3 ceramics; Microwave sintering; Phase formation; Mechanical properties

This Article

  • 2021; 22(3): 296-300

    Published on Jun 30, 2021

  • 10.36410/jcpr.2021.22.3.296
  • Received on Jun 18, 2020
  • Revised on Dec 11, 2020
  • Accepted on Dec 29, 2020

Correspondence to

  • Bingliang Liang

  • School of Materials Science and Engineering, Nanchang Hangkong University, No.696, South Fenghe Avenue, Nanchang 330063, Jiangxi Province, P.R. China
    Tel : +86 791 8386 3034 Fax: +86 791 8645 3203

  • E-mail: lbl@nchu.edu.cn