Effects of MgO addition on the phase, mechanical properties, and microstructure of zirconia-toughened alumina added with CeO2 (ZTA-CeO2) ceramic composite

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:595

Article

Rejab, Nik Akmar¹  Azhar, Ahmad Zahirani Ahmad²  Kian, Khoo Seng¹  Ratnam, Mani Maran³  Ahmad, Zainal Arifin¹ 

[1] Univ Sains Malaysia, Struct Mat Niche Area, Sch Mat & Mineral Resources, Nibong Tebal 14300, Penang, Malaysia

[2] Int Islamic Univ Malaysia, Dept Mfg & Mat Engn, Fac Engn, Kuala Lumpur 50728, Malaysia

[3] Univ Sains Malaysia, Sch Mech, Nibong Tebal 14300, Penang, Malaysia

关键词: Microstructure;    Vickers hardness;    Fracture toughness;    MgO;   

DOI  :  10.1016/j.msea.2013.11.091

来源: Elsevier

【 摘 要 】

The effects of MgO addition on properties such as density, firing shrinkage, microstructure, Vickers hardness, and fracture toughness of ZTA-CeO2 ceramics composites were investigated. The amount of CeO2 used in the experiment was fixed at 5.0 wt% while the MgO addition was varied from 0 wt% to 2.0 wt%. Each composition was weighed, mixed, and pressed using hydraulic press under 300 MPa into 13 mm pellets. The pellets were sintered at 1600 degrees C for 4 h under pressureless condition. Vickers hardness and fracture toughness of the sintered samples were measured using the Vickers indentation method. Based on the SEM microstructures, elongated secondary phase, i.e. MgAl11CeO19, started to occur at 0.5 wt% MgO. This elongated phase was responsible for the increase in fracture toughness of the ceramic composites. Similarly, the addition of more than 0.5 wt% MgO produced another secondary phase (MgAl2O4), as detected by XRD. This phase was shown to have low intrinsic fracture toughness. Therefore, the sample with 0.5 wt% MgO showed the optimum properties with the highest fracture toughness (9.14 MPa root m) and Vickers hardness (1591 HV) values. (C) 2013 Elsevier B.V. All rights reserved.

【 授权许可】

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