Electrical and Mechanical Properties of ZrB₂-Based Composite Ceramic

Abstract:

The ZrB₂-SiC composite ceramic was prepared using Al₂O₃ and Y₂O₃ as additives through pressureless sintering under 1800°C. The electrical and mechanical properties were studied with the different mass ratio of ZrB₂ and SiC. The microstructure and phase transformation of the ZrB₂-SiC composites ceramic were characterized by scanning electron microscopy. Results show that the densities of the samples are decreased with the decrease of the mass ratio of ZrB₂ and SiC while the resistivities are increased. When the mass ratio of ZrB₂ and SiC is 4 the resistivity reaches 14μΩ•mm while the density is 4.85g/cm³. When the mass ratio of ZrB₂ and SiC is13:7, the flexural strength reaches the max value and toughness reaches the minimum value. The flexural strength reaches 233Mpa and the toughness reaches 4.51 Mpa• m ^1/2. The changes of the properties of the ceramic were analyzed through the microstructure and the conduction mechanism was studied.

• Periodical: Key Engineering Materials (Volumes 512-515)
• Pages: 744-747
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.512-515.744
• Online since: June 2012
• Authors: Yan Yan Wang, Kai Liu, Chang Ling Zhou, Chong Hai Wang, Rui Xiang Liu, Yi Na Luan
• Keywords: Electrical Properties, Pressureless Sintering, Resistivity, ZrB₂-Based Ceramic

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