SYNTHESIS AND PROPERTIES OF NI-ALPHA-AL2O3 COMPOSITES VIA SOL-GEL

Authors
RODEGHIERO ED TSE OK CHISAKI J GIANNELIS EP
Citation
Ed. Rodeghiero et al., SYNTHESIS AND PROPERTIES OF NI-ALPHA-AL2O3 COMPOSITES VIA SOL-GEL, Materials science & engineering. A, Structural materials: properties, microstructure and processing, 195(1-2), 1995, pp. 151-161
Citations number
20
Categorie Soggetti
Material Science
Journal title
Materials science & engineering. A, Structural materials: properties, microstructure and processing → ACNP
ISSN journal
09215093
Volume
195
Issue
1-2
Year of publication
1995
Pages
151 - 161
Database
ISI
SICI code
0921-5093(1995)195:1-2<151:SAPONC>2.0.ZU;2-G
Abstract
Ni-alpha-Al2O3 metal-ceramic composites with metal loadings ranging fr om 33 to 67 vol.% were synthesized via a sol-gel (both polymeric and c olloidal) technique. The polymeric route involves introducing nickel f ormate during the hydrolysis and condensation of aluminum isopropoxide while the colloidal route involves precipitating Ni(OK), onto boehmit e particles. Transformation to Ni-alpha-Al2O3 composites is accomplish ed by calcination in a reducing environment followed by hot pressing a t about 1400 degrees C in an oxygen partial pressure of 10(-12) atm. T he composites exhibit a highly interconnected microstructure, composed of continuous Ni and alumina networks, and enhanced fracture properti es compared with pure alumina.