Computation of Parameters of the Self-Propagating High-Temperature Synthesis

Abstract

Computation of parameters of the self-propagating high-temperature synthesis (SHS), which is characterized by the combustion propagation through a matrix of compacted reactive particles and is recognized to hold the practical significance in producing novel solid materials, is presented. The SHS process falls into a category of the flame propagation, because a reaction initiated at one end of a compacted medium by use of the external heating source self-propagates through an unburned medium, in the form of a combustion wave. The high temperature needed for synthesis can be supplied by the self-sustained exothermic chemical reactions. The potential advantages of this process are as follows: rapid synthesis; self-heating; energy savings; self-purification due to enhanced impurity outgassing; near-net-shape fabrication, etc. Compounds synthesized are being considered for use as electronic materials, materials resistant to wear, corrosion, and heat. Furthermore, it can even be applied to the synthesis of shape-memory alloys, hydrogen-storage alloys, and high-temperature superconductors. Thus, it is now well recognized that the SHS process can be of practical significance in producing novel solid materials. Although it has proven effective, it was also recognized that in order to control the manufacturing process, dependence of flame propagation speed on various dominant parameters is indispensable. In addition, range of flammability with respect to various parameters is urgently required because the ignition cannot be maintained outside the range of flammability. Of course, dependence on various parameters is also required in preventing flame extinction.