- Title
- Reaction kinetics in Ti3SiC2 synthesis studied by time-resolved neutron diffraction
- Creator
- Wu, Erdong; Riley, Daniel Phillip; Kisi, Erich Herold; Smith, R. I.
- Relation
- Journal of the European Ceramic Society Vol. 25, no. 15, p. 3503-3508
- Publisher
- Elsevier Science
- Resource Type
- journal article
- Date
- 2005
- Description
- The reactive sintering of 3Ti/SiC/C to form the ternary carbide Ti3SiC2, previously found to involve the intermediate phases TiCx and Ti5Si3Cx, was investigated by time-resolved neutron powder diffraction. The kinetics of Ti3SiC2 formation from the intermediate phases TiCx Ti5Si3Cx (x <= 1) and a small amount of free C was determined. The crystallization rate of the Ti3SiC2 phase was determined through quantitative analyses of the diffraction patterns collected at different temperatures and is initially well-described by the Mehl-Avrami-Johnson equation. The activation energy was found to be 380 +/- 10 kj/mol and the Avrami exponent 3.0 +/- 0.2. The Avrami exponent decreases to close to I when more than half of the crystallization process was completed. This indicates a change in the mechanism of Ti3SiC2 crystal growth from unrestricted two or three-dimensional growth in the a-b planes to one-dimensional growth only, due to interaction of the growing,disk-like crystals and cessation of growth in the preferred direction.
- Subject
- sintering; carbides; kinetics; Ti3SiC2; neutron diffraction; high-temperature synthesis; powder diffraction; phase change; microstructure; nucleation; growth
- Identifier
- uon:612
- Identifier
- http://hdl.handle.net/1959.13/24684
- Identifier
- ISSN:0955-2219
- Language
- eng
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