Sintering ZrO{sub 2}/TiC composites with TiH{sub 2}: The role of transient liquid phase and of substoichiometry

Journal Article · Sun Oct 01 04:00:00 EDT 1995 · Journal of the American Ceramic Society

DOI:https://doi.org/10.1111/j.1151-2916.1995.tb08034.x· OSTI ID:131529

Krell, A; Blank, P ^[1]; Pippel, E; Woltersdorf, J ^[2]

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1. Fraunhofer Inst. for Ceramic Technologies and Sintered Materials, Dresden (Germany)
2. Max-Planck-Inst. for the Physics of Microstructures, Halle (Germany)

Sintering tetragonal ZrO{sub 2} with 35 vol% TiC results in a microstructure where all grain facets are free of amorphous interfaces independent of sintering aids as TiH{sub 2} or MgO/Y{sub 2}O{sub 3}; grain sizes are below 1 {micro}m. With substoichiometric TiC{sub 1{minus}x}, a relative density of 95% and closed porosity are obtained at a lower sintering temperature than with stoichiometric TiC, but subsequent cladless hot isostatic pressing (HIP) is required to achieve 99% density. High densities of 98% accompanied by good mechanical properties become possible by pressureless sintering with the use of TiH{sub 2}. MgO/Y{sub 2}O{sub 3} doping also promotes densification, but results in less transformable zirconia and increases the number and size of amorphous triple junctions. The consequences are a lower fracture toughness and strength.

• Sponsoring Organization: USDOE
• OSTI ID: 131529
• Journal Information: Journal of the American Ceramic Society, Journal Name: Journal of the American Ceramic Society Journal Issue: 10 Vol. 78; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BULK DENSITY
COMPOSITE MATERIALS
GRAIN SIZE
LIQUIDS
MAGNESIUM OXIDES
MECHANICAL PROPERTIES
MICROSTRUCTURE
POROSITY
POWDERS
SINTERING
TEMPERATURE DEPENDENCE
TITANIUM CARBIDES
TITANIUM HYDRIDES
YTTRIUM OXIDES
ZIRCONIUM OXIDES