Hot pressing reactive

Beryllides and Borides. CrBe2 and CrBj have been prepared by the reactive hot-pressing method and studied by X-ray diffraction. The crystal structure of the interstitial boride, CrB j, has been determined. The results suggest that the Cr atom occupies a high symmetry position.The ternary complex boride UCrB has been shown by two independent crystallographic studies to have the YCrB -type structure. ... 

F. Monteverde, Progress in the Fabrication of Ultra-High-Temperature Ceramics In Situ Synthesis, Microstructure and Properties of a Reactive Hot-Pressed HfB2-SiC Composite, Comp. Sci. Tech., 65, 1869-79 (2005). 

Hamano K, Kanzaki S (1977) Fabrication of transparent spinel ceramics by reactive hot-pressing. J Ceram Soc Jpn 85 225-230... 

J.W. Zimmermann, G.E. Hilmas, W.G. Fahrenholtz F. Monteverde, and A. Bellosi, Fabrication and properties of reactively hot pressed ZrB2-SiC ceramics, Journal of the European Ceramic Society, 27 2729-2736 (2007). 

Fig. 3.92 Typical dislocations in Ti3SiC2 produced by reactive hot pressing singie disiocations (A) arrays of parallel straight dislocations within a grain (S) dislocations bounding stacking faults (O dislocations at grain boundaries (D) [25]. With kind permission of Wiiey and Sons...

In an additional example of SF, Fig. 3.92 illustrates their existence in Ti3SiC2-Undeformed and deformed samples of Ti3SiC2, fabricated by the reactive hot pressing of Ti, SiC, and graphite, were characterized by TEM. Figure 3.92 presents micrographs of undeformed ceramic specimens. The basal plane dislocations are mobile and multiply as a result of deformation at RT. Direct evidence of dislocation mobility and multiplication in Ti3SiC2, as a result of deformation, may be seen in Fig. 3.93. 

Reactive hot pressing of a mixture of powdCTS has been used successfully to produce composites (69,70). Densification is more readily achieved in this case when compared to the reaction sintering process described in Chapto 11, and this is due to the enhanced driving force for densification as well as the ability of the applied pressure to break down unfavorable microstructural features produced by the reaction, such as particle-particle bridges that constrain sintering. 

Reaction-sintering, sintering (q.v.) of a two-component powder, in which a chemical reaction also takes place to produce a dense single phase or a multiphase material. Ceramic-ceramic composites may be thus produced - e.g. dense mullite zirconia composites from zircon and alumina. See also reactive HOT-PRESSING. 

Reactive Chemical Vapour Deposition. (RCVD). A variant of CVD, in which more than one material is deposited at the same time, to optimise the desired properties of the composite coating. RESA (Reactive Electrode Submerged Arc Technique). Fine (lO-lOOOnm anhydrous oxide powders are made as sols by striking an arc between two metal electrodes submerged in a dielectric liquid, typically water. (A. Kumar and R. Roy J Mater Res 3 (6), 1988 p. 1373). Reactive Hot-Pressing. A term proposed by A. C. D. Chaklader (Nature, 206, 392,... 

Guo-Jun Zhang, Zhen-Yan Deng, Naoki Kondo, Jian-Feng Yang, Tatsuki Ohji. Reactive Hot Pressing of ZrB2-SiC Composites. Journal of the American Ceramic Society 2000 83 2330. 

G.J. Zhang, Z.Y. Deng, N. Kondo, J.F. Yang and T. Ohji Reactive hot pressing of ZrB2-SiC composites. Journal of the American Ceramic Society 83,2330-2332 (2000). 

G. J. Zhang, J. F. Yang, M. Ando and T. Ohji. Reactive Hot Pressing of Alumina-Silicon Carbide Nanocomposite. Journal of the American Ceramics Society. 2004, 87(2), 299-301... 

L. Rangaraj, G. Divakar, and V. Jayaram, Fabrication and mechanisms of densification of ZrBj-based ultra-high temperature ceramics by reactive hot pressing, ]. Ear. Ceram. Soc., 30 129-138, 2010. 

Monteverde, F. (2005). ftognessinthe fabrication of ultra-high-temperature ceramics in situ synthesis, microstructure and properties of a reactive hot-pressed HfB - SiC composite. Comp. Sci. Tech.,65,1869-1879.doi 10.1016/j.compscitech.2005.04.003. 

Nachiappan, C., Rangaraj, L., Divakar, C., Jayaram, V. (2010). Synthesis and densification of monolithic ZrC by reactive hot pressing. Journal of the American Ceramic Society, 93(5), 1341-1346. 

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