Effect of Titania and Magnesia on the Physical Properties of Zirconia Toughened Alumina

Abstract:

ZTA based ceramic composite system is widely accepted as cutting tools for many of these harder and wear resistant workpiece materials. This is due to their beneficial mechanical properties i.e. high temperature strength, high hardness and ability to maintain its cutting edge shape at higher temperatures. Although a lot of works have focused on the effect of various sintering additives on the ZTA ceramic system, the effect of Magnesia (MgO) and Titania (TiO₂) on ZTA has not yet been studied. In this work, the physical properties of Zirconia Toughened Alumina (ZTA) ceramic composite with MgO and TiO₂ as additives was investigated. The composition of TiO₂ varied from 0 wt% to 3.5 wt% whereby other materials such as Al₂O₃, Yttria Stabilized Zirconia (YSZ) and MgO were kept at constant weight percentage. Sintered samples were then tested and analyzed by XRD, Vickers hardness and high precision densimeter to investigate phase content, hardness value and densification respectively. Results showed that the solubility limit of TiO₂ in ZTA-MgO ceramic composites is at 2.0 wt%. Further addition of TiO₂ resulted in the formation of secondary phase known as Zirconium titanium oxide (Zr_0.35TiO_0.65O₂) which deteriorate the properties exhibited by ZTA-MgO-TiO₂ ceramic composites.

• Periodical: Materials Science Forum (Volume 840)
• Pages: 82-86
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.840.82
• Online since: January 2016
• Authors: Hanisah Manshor, Wan Muhammad Ihsan Wan Sabri, Abdul Wahid Ramli, Ahmad Zahirani Ahmad Azhar, Ezzat Chan Abdullah*, Zainal Arifin Ahmad
• Keywords: Density, TiO₂, Vickers Hardness, XRD, Zirconia Toughened Alumina (ZTA)

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