Effect of SiC on interfacial reaction and sintering mechanism of TiB{sub 2}

Journal Article · Thu Jun 01 04:00:00 EDT 1995 · Journal of the American Ceramic Society

DOI:https://doi.org/10.1111/j.1151-2916.1995.tb08858.x· OSTI ID:82629

Torizuka, Shiro ^[1]; Sato, Kaoru; Nishio, Hiroaki ^[2]; Kishi, Teruo ^[1]

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1. Univ. of Tokyo (Japan). Research Center for Advanced Science and Technology
2. NKK Corp., Kawasaki (Japan)

Compacts of TiB{sub 2} with densities approaching 100% are difficult to obtain using pressureless sintering. The addition of SiC was very effective in improving the sinterability of TiB{sub 2}. The oxygen content of the raw TiB{sub 2} powder used in this research was 1.5 wt%. X-ray photoelectron spectroscopy showed that the powder surface consisted mainly of TiO{sub 2} and B{sub 2}O{sub 3}. Using vacuum sintering at 1,700 C under 13--0.013 Pa, TiB{sub 2} samples containing 2.5 wt% SiC achieved 96% of their theoretical density, and a density of 99% was achieved by HIPing. TEM observations revealed that SiC reacts to form an amorphous phase. TEM-EELS analysis indicated that the amorphous phase includes Si, O, and Ti, and X-ray diffraction showed the reaction to be TiO{sub 2} + SiC {yields} SiO{sub 2} + TiC. Therefore, the improved sinterability of TiB{sub 2} resulted from the SiO{sub 2} liquid phase that was formed during sintering when the raw TiB{sub 2} powder had 1.5 wt% oxygen.

• Sponsoring Organization: USDOE
• OSTI ID: 82629
• Journal Information: Journal of the American Ceramic Society, Journal Name: Journal of the American Ceramic Society Journal Issue: 6 Vol. 78; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BULK DENSITY
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
COMPOSITE MATERIALS
INTERFACES
MICROSTRUCTURE
SCANNING ELECTRON MICROSCOPY
SILICON CARBIDES
SILICON OXIDES
SINTERING
TITANIUM BORIDES
TITANIUM OXIDES
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION
X-RAY SPECTROSCOPY