Effects of Cr 2 O 3 addition on the phase, mechanical properties, and microstructure of zirconia-toughened alumina added with TiO 2 (ZTA–TiO 2 ) ceramic composite

The mechanical properties and microstructure of zirconia-toughened-alumina ceramic composite doped with nanoparticle of MgO is investigated. The nanoMgO weight percent was varied from 0.3 wt % to 1.3 wt %. Each batch of composition was mixed using ultrasonic cleaner and mechanical stirrer, uniaxially pressed and sintered at 1600 °C for 4 h in pressureless conditions. Analysis of bulk density, Vickers hardness and microstructural observation has been carried out. Results of Vickers hardness increased linearly with addition of more nanoMgO until a certain composition. Maximum Vickers hardness obtained was 1740HV with 1.1 wt % MgO. Furthermore, microstructural observations show that the Al2O3 grain size depends on the particle size of MgO, and is directly related to its hardness property.

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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 ◽

10.1016/j.msea.2013.11.091 ◽

2014 ◽

Vol 595 ◽

pp. 18-24 ◽

Cited By ~ 27

Author(s):

Nik Akmar Rejab ◽

Ahmad Zahirani Ahmad Azhar ◽

Khoo Seng Kian ◽

Mani Maran Ratnam ◽

Zainal Arifin Ahmad

Keyword(s):

Mechanical Properties ◽

Ceramic Composite ◽

Zirconia Toughened Alumina

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Effect of Cr2O3-TiO2 Addition on the Physical Properties of Zirconia Toughened Alumina

Materials Science Forum ◽

10.4028/www.scientific.net/msf.840.34 ◽

2016 ◽

Vol 840 ◽

pp. 34-38 ◽

Cited By ~ 3

Author(s):

Hanisah Manshor ◽

Abdul Wahid Ramli ◽

Ahmad Zahirani Ahmad Azhar ◽

Ezzat Chan Abdullah ◽

Zainal Arifin Ahmad

Keyword(s):

Mechanical Properties ◽

Physical Properties ◽

Magnesium Oxide ◽

Cerium Oxide ◽

Vickers Hardness ◽

Ceramic Composite ◽

Powder Materials ◽

Powder Mixtures ◽

Cutting Insert ◽

Zirconia Toughened Alumina

Zirconia toughened alumina (ZTA) has good mechanical properties and widely used in cutting insert application. Although the ZTA is well known of its good mechanical properties, its still can be improved in order to produce better properties. It can be done by adding additives as reinforcement such as magnesium oxide (MgO), cerium oxide (CeO), titania (TiO2) and chromia (Cr2O3). The effect of TiO2-Cr2O3 addition on the physical properties of ZTA were investigated in this study. The composition of TiO2 was varied from 0 wt% to 3.5 wt% while Cr2O3 was fixed at 5 wt%. The starting powder materials were mixed by wet mixing for 30 minutes in acetone. Then the powder mixtures were hydraulically pressed at 260 MPa. The green pellets were sintered at 1600°C for 1 hour using an electrical furnace in presureless condition. The results were characterized by XRD, density, and also Vickers hardness. The ZTA-Cr2O3-TiO2 ceramic composite achieved the highest density of 4.1 g/cm3 and Vickers hardness of 1919 HV prior to the addition of 2.0 wt% TiO2. Therefore, it can be decisively concluded that the addition of Cr2O3-TiO2 does affected the properties of ZTA.

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Mechanical Properties of Zirconia Toughened Alumina Composites with TZP Partially Nanostructured Sintered by Liquid Fase

Materials Science Forum ◽

10.4028/www.scientific.net/msf.591-593.436 ◽

2008 ◽

Vol 591-593 ◽

pp. 436-440

Author(s):

João Marcos K. Assis ◽

Francisco Piorino Neto ◽

Francisco Cristóvão Lourenço de Melo ◽

Maria do Carmo de Andrade Nono

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Weibull Modulus ◽

Bending Test ◽

Sintering Aid ◽

Zirconia Composites ◽

Alumina Composites ◽

Grain Size And Shape ◽

Zirconia Toughened Alumina ◽

Zirconia Powders

A comparative study between alumina added niobia ceramics and two alumina zirconia composites from nanostructured TZP (7% and 14% weight) was made. On this composites the zirconia were yttria stabilized and the alumina were submicron structured. As sintering aid a mixture of magnesia, niobia and talc were used on all samples. The sintering was performed at 1450 oC during 60 minutes. The characteristic grain size and shape of an alumina and zirconia powders, aggregates and agglomerates were characterized. The sintering ceramics were evaluated through hardness, fracture toughness and 4 point bending test. Weibull statistic was applied on the flexural results. Although the fracture toughness result from ZTA were lower, and seems to be affected by the liquid fase, the hardness and Weibull modulus were higher than alumina niobia. The grains size and the homogeneity of its distributions on the microstructure of this ceramics was correlated to these higher values. The results from these alumina zirconia composites showed a potential to apply as a ballistic armor material.

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