Temperatures self-propagating synthesis

High temperature self propagating synthesis (SHS) Coarse powder with high [214] /LSi3N4 content... 

Traditionally, selenides have been synthesized at high temperature (>500 °C) by solid-state reaction [131] or self-propagating synthesis [132]. A high-energy ball milling method at room temperature has also been used [133], however, the product quality was difficult to control. In liquid ammonia, a low-temperature route to selenides was developed [134]. Organometallic precursors have been used to obtain... 

International Journal of Self-propagating High-temperature Synthesis, Allerton Press, New York, from 1992. 

Intermetallic compound formation may be observed as the result from the diffusion across an interface between the two solids. The transient formation of a liquid phase may aid the synthesis and densification processes. A further aid to the reaction speed and completeness may come from the non-negligible volatility of the component(s). An important factor influencing the feasibility of the reactions between mixed powders is represented by the heat of formation of the desired alloy the reaction will be easier if it is more exothermic. Heat must generally be supplied to start the reaction but then an exothermic reaction can become self-sustaining. Such reactions are also known as combustion synthesis, reactive synthesis, self-propagating high-temperature synthesis. 

Combustion Synthesis. Besides solid-state reactions requiring heating even for several days at high temperatures to be completed, fast reactions are also known which give their products in minutes or seconds. Several nearly equivalent names are used for these reactions such as solid-state combustion, combustion synthesis, self-propagating (self-sustained) high-temperature synthesis. Solid state direct combinations and solid-state metathesis have been described. 

Figure 6.12. Self-propagating high-temperature synthesis of NiAl (Fan etal. 2001). The temperature- time profile observed during the passage of a combustion wave is shown.

Figure 6.16. Metathesis synthesis of AIN. Temperature trends in the self-propagating reactions (Janes et al. 2003). (a) A1C13 + 0.5Ca3N2 (in an insulating ceramic cap) (b) A1C13 + 0.5Ca3N2 (in a steel vessel) (c) A1C13 + Li3N (d) 0.5A12S3 + Li3N.

TABLE 9.5 Compounds Produced by Self-Propagating, High-Temperature Synthesis (SHS)a... 

SIDMT. Metal Hydrides Manufacturing. Coals Increase the Hydrogen content in the Metallic Hydrides. Synthesize Metallic Hydrides by conventional techniques and by Self-propagation High Temperature Synthesis. 

Combustion synthesis, also known as self-propagating high temperature synthesis,... 

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