Transactions of the INDIAN CERAMIC SOCIETY Vol. 72 2013
Effect of Zirconia Content and Powder Processing on
Mechanical Properties of Gelcasted ZTA Composite
M. Khoshkalam*, M. A. Faghihi-Sani and A. Nojoomi
pages 175-181
DOI:10.1080/0371750X.2013/851618
Abstract
Addition of fine zirconia particles in the alumina matrix in order to produce ZTA composite is a well-known method
for improving the mechanical properties of alumina ceramics such as flexural strength and fracture toughness.
Increasing homogeneity and reducing alumina grain size are two key factors for achieving proper mechanical
properties in this ceramic matrix composite. In this work two batches of ZTA powder precursor were prepared
through mixing of alumina and zirconia by ball milling and in situ synthesis of ZTA composite via solution combustion
method. The bending strength testing samples were fabricated through gel-casting process. The effects of different
powder processing methods as well as zirconia contents on microstructural homogeneity and mechanical properties
of ZTA composites were investigated. The samples produced by solution combustion synthesized powder yielded
higher homogeneity, finer microstructure and higher flexural strength. Results showed an upswing in the fracture
toughness for the synthesized samples even up to 20 vol% zirconia, while the mixed samples depicted optimum
fracture toughness in 10 vol% zirconia content.