Wh. Tuan et al., EFFECT OF SINTERING ATMOSPHERE ON THE MECHANICAL-PROPERTIES OF NI AL2O3 COMPOSITES/, Journal of the European Ceramic Society, 17(5), 1997, pp. 735-741
In the present study, nickel-toughened aluminas are prepared by sinter
ing in either hydrogen or carbon monoxide. By choosing suitable sinter
ing temperatures, the size of nickel inclusions is the same in the com
posites sintered in H-2 and CO. The addition of nickel inclusions enha
nces the toughness of alumina. As the inclusion size is bigger than 2
. 7 mu m, microcracks are formed at the interface in the composites si
ntered in H-2. The toughness and strength of the composites are thus r
educed. However, no microcracks are observed at the interface in the c
omposites sintered in CO. The toughness and strength of the composites
sintered in CO is therefore higher than those of the composites sinte
red in H-2. For example, for the composite containing 20 vol% inclusio
ns and sintered in CO, the roughness is 9 MPa m(0 . 5) and the strengt
h is 630 MPa. (C) 1997 Elsevier Science Limited. All rights reserved.