Back to Search Start Over

Densification and properties of transition metal borides-based cermets via spark plasma sintering

Authors :
Bikramjit Basu
Doh-Yeon Kim
G.B. Raju
Thiruvenkatam Venkateswaran
Source :
Journal of the European Ceramic Society. 26:2431-2440
Publication Year :
2006
Publisher :
Elsevier BV, 2006.

Abstract

Engineering borides like TiB 2 and ZrB 2 are difficult to sinter materials due to strong covalent bonding, low self-diffusion coefficient and the presence of oxide layer on the powder particles. The present investigation reports the processing of hard, tough and electrically conductive transition metal borides (TiB 2 and ZrB 2 ) based cermets sintered with 6 wt.% Cu using spark plasma sintering (SPS) route. SPS experiments were carried out with a heating rate of 500 K/min in the temperature range of 1200–1500 °C for a varying holding time of 10–15 min and the optimization of the SPS conditions is established. A maximum density of ∼95% ρ th in ZrB 2 /Cu and ∼99% ρ th in TiB 2 /Cu is obtained after SPS processing at 1500 °C for 15 min. While the optimized TiB 2 /Cu cermet exhibits hardness and fracture toughness of ∼17 GPa and ∼11 MPa m 1/2 , respectively, the optimized ZrB 2 /Cu cermet has higher hardness of ∼19 GPa and fracture toughness of ∼7.5 MPa m 1/2 , respectively. High electrical conductivity of ∼0.20 MΩ −1 cm −1 (TiB 2 /Cu) and ∼0.15 MΩ −1 cm −1 (ZrB 2 /Cu) are also measured with the optimally sintered cermets.

Details

ISSN :
09552219
Volume :
26
Database :
OpenAIRE
Journal :
Journal of the European Ceramic Society
Accession number :
edsair.doi...........d138b1dc07d705b5ddd598118b9f6f0b
Full Text :
https://doi.org/10.1016/j.jeurceramsoc.2005.05.011