Mechanical self-propagating synthesis

C. He and G. C. Stangle, The mechanism and kinetics of the niobium-carbon reaction under self-propagating synthesis-like conditions, J. Mater. Res. 1995,10, 2829-2841. 

Solid-phase reactions are usually activated by high-temperature treatment [1-4]. However, the practical efficiency of this process is rather low since the diffusion rate through a product layer is small, no tight contacts between the particles of components are provided, a particle size distribution is non-uniform, etc. Therefore, the search for new methods of performance of solid-phase reactions is carried out. Some new methods are successfully used for these purposes. These methods include, for example, self-propagating high-temperature synthesis [5], shock waves [6,7], mechanical activation of mixtures in grinding apparatus [8-15]. The latter method becomes more widely used at present due to its relative simplicity and availability. 

Many borides can be synthesized by novel synthetic methods, inclnding shock-induced chemical reactions, mechanical alloying by ball milling, and self-propagating high-temperature synthesis. In these methods, intimately mixed elemental powders are brought to react by a rapid pressure increase, mechanical deformation including local... 

Rogachev, A. S., Khomenko, I. O., Varma, A., Merzhanov, A. G., and Ponomarev, V. I., The mechanism of self-propagating high-temperature synthesis of nickel aluminides. Part II Crystal structure formation in a combustion wave. Int. J. SHS, 3,239 (1994a). 

Wang, L., Wixom, M. R., and Tompson, L. T., Structural and mechanical properties of TiB2 andTiC prepared by self-propagating high-temperature synthesis/dynamic compaction. J. Mater. Sci., 29,534 (1994a). 

Gras, Ch., Gaffet, E., Bernard, F., Chariot, F., and Niepce, J.-C., Mechanically activated self-propagating high temperature synthesis (MASH) applied to the MoSi2 and FeSi2 phase formation. 

Mechanically induced self-propagating reaction — ignition of self-propagating high-temperature synthesis (SHS) (see) by means of mechanochemical treatment, preceded with an activation period, that is, ignition time, during which particle and crystallite size reduction, mixing and defect formation take place. 

W-C Lee, S-L Chung. Ignition phenomena and reaction mechanisms of the self-propagating high-temperature synthesis reaction in the Ti + C system. J Mater Sci 30 1487, 1995. 

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