Preparation and Characterization of Alumina Zirconia Composite Ceramics

• Published in: Integrated ferroelectrics 2023-11, Vol.239 (1), p.12-20
• Main Authors: Suthapintu, Aekasit, Rittidech, Aurawan
• Format: Article
• Language: English
• Subjects: Aluminum oxide; Bulk density; Ceramics; Fracture toughness; Grain size; Knoop hardness; Magnesium oxide; Mathematical analysis; Mechanical properties; MgO; Phase composition; Photomicrographs; Physical properties; Rietveld refinement; Yttrium oxide; Zirconium dioxide; ZrO
• ISSN: 1058-4587; 1607-8489
• DOI: 10.1080/10584587.2023.2234605

The composite ceramics between Al 2 O 3 (6 mol%MgO) and ZrO 2 (4 mol%Y 2 O 3 ) were prepared in the Al 2 O 3 (6 mol%MgO added: ZrO 2 (4 mol%Y 2 O 3 added) ratios of 20:80, 35:65, 50:50, 65:35 and 80:20. All of samples were sintered using two stage sintering routes with the first temperature (T 1 ) at 1600 °C for 30 min and the second temperature (T 2 ) at 1450 °C for 5 h. The physical properties were characterized from percentage of shrinkage and bulk density. It can be found their tend to decrease with Al 2 O 3 (6 mol%MgO) content increase. XRD patterns were showed combination main phase of rhombohedral of Al 2 O 3 and monoclinic, cubic, tetragonal of ZrO 2 . Rietveld refinement were used to calculate the percentage of phase composition. All of samples were revealed weight percentage of main composition as m-ZrO 2 c-ZrO 2 t-ZrO 2 and r- Al 2 O 3 in different ratios. It can be found, sample with more content of ZrO 2 was showed higher weight percentage of c-ZrO 2 . The high intensity of Al 2 O 3 peak was appeared from sample with high Al 2 O 3 concentration. SEM micrographs reveal morphology of grain such as grain shape and size of grains. The average grain size value is between 0.81 and 1.07 µm and the size of grain tend to increase with high Al 2 O 3 content. EDX technique were analyzed element compositions of Al 2 O 3 (6 mol%MgO): ZrO 2 (4 mol%Y 2 O 3 ) and EDX spectra were showed wt.% element of Al, Zr, O Y and Mg which is confirmed molecular formular. Moreover, EDX method is identified square shape of Al 2 O 3 (6 mol%MgO) and round shape of ZrO 2 (4 mol%Y 2 O 3 ). The mechanical properties were measured by Vickers and Knoop hardness that were used for calculating the fracture toughness value. It can be found that the optimum mechanical properties were obtained from composite ceramic of 0.35Al 2 O 3 (6 mol%MgO): 0.65ZrO 2 (4 mol%Y 2 O 3 ) which is showed the highest of fracture toughness value about 0.38 GPa.m 1/2 .