Reactant compact and product microstructures for TiC, TiB2, and TiC/TiB2 from SPS processing. [Self-Propagating Synthesis]

Conference · Mon Oct 01 04:00:00 EDT 1990 · Ceramic Engineering and Science Proceedings; (USA)

OSTI ID:6152086

Rice, R W

Microstructures of TiC, TiB2 and TiC/TiB2 mixtures produced by self-propagating synthesis (SPS) were examined. Porosity levels were determined mainly by other process parameters, e.g., whether the part was unconstrained, constrained, or hot-pressed during the reaction. Pore sizes were determined mainly by outgassing in the former two. Grain sizes were mainly a function of the composition, and secondarily of fine residual porosity between grains. Thus, TiB2 yielded larger grains for comparable densities than TiC because of hgher reaction temperatures, while TiC/TiB2 mixtures had finer grain sizes due to mutual inhibition of grain growth. However, these SPS-produced grain sizes tend to be somewhat greater than those commonly achievable by conventional hot-pressing. Considerable evidence of molten Ti is seen in these SPS products, including internal extrusion of Ti filaments. Evidence of thermal etching is seen on grains of TiC/TiB2 and especially TiB2. 13 refs.

• OSTI ID: 6152086
• Report Number(s): CONF-900160--
• Conference Information: Journal Name: Ceramic Engineering and Science Proceedings; (USA) Journal Volume: 11
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
BORIDES
BORON COMPOUNDS
CARBIDES
CARBON COMPOUNDS
CERAMICS
CRYSTAL STRUCTURE
FABRICATION
GRAIN SIZE
HIGH TEMPERATURE
HOT PRESSING
MATERIALS WORKING
METALLURGY
MICROSTRUCTURE
POROSITY
PRESSING
SIZE
SYNTHESIS
TITANIUM BORIDES
TITANIUM CARBIDES
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS