| Self-propagating High temperature synthesis (SHS) as a new kind of materials fabricating technology has been paid attention by material scientific workers all over the word. As an advance material fabrication technology, it had been appraised by "rapid, simple process, and economic". However after almost half century of its foundation, this technology is still only been used to product some advanced ceramics powders, which must due to its bad controllability. Because of lots complex physic-chemic changes under that "rapid, simple process", there need more studies to enclose those ambiguous rules in SHS. In this paper, we had studied the dynamics during SHS by theory imitation by the aid of computer. With a new combustion model, lots of combustion phenomena had been explained perfectly, which would help for controlling the rapid SHS process. The relation ship between the technology way of SHS and the macro- and micro- structures of SHS products also were studied in this paper that was believed helpful for the designing and fabrication of materials. These concrete works are the following:1, a new heterogonous SHS model had been proposed, which first included all the relative materials characters, such as reactants particle sizes, changeable heat-conductivity and mass diffusion during SHS and so on, and its chemical reaction characters, initial combustion status. This new model made a more precise prediction about the SHS combustion way and its Technological characters possible.2, with the heterogonous SHS model, lots of combustion way had been imitated by change systems relative factors and the rule of the combustion way change had also been studied, chemical reaction in these systems was controlled by a single mechanism. The calculated results showed that the rule from an inflammable one to an un-continual combustion one, and to a continual one were different. From the un-continual combustion model, and to a continual model there is a gradual transformation process, while an abrupt change in the process from an inflammable model to un-continual combustion model, which means there exits a critical value in the later. Results also showed that the combustion wave of a continual one could change from the start unstable way, due to the effect of ignition, to a stable propagation way. This self-stabilization character means the combustion process of the model is a pure one to thermal equilibrium.3, considering of the combustion reaction controlled by multi-mechanism, calculated results showed combustion wave of the continual combustion also changed to an unstable combustion way, the combustion temperature and wave propagating velocity changed periodically. By changing factors about the reaction mechanism, results showed the periodicoscillation combustion was mainly caused by the effect and feedback between chemical reaction and thermal conduction. In the study of the diffusion-reaction equation, the mass diffusion was believed could cause some order-behavior in the reaction, however in SHS this effect wasn't found. It was believed due to that mass could mainly diffuse in a fixed direction in SHS, the combustion wave's direction.4, In order to validating the heterogeneous SHS model, we calculated Ti-C system's combustion. Comparing the calculated results and the experimental results, good coherence was found, which means after importing relative materials factors and initial condition the model had reflected main truth and was valid for precise prediction of the SHS.5, SHS is a process far from equilibrium, which is always accompanied by rich self-order behavior, such as oscillation, spin, stationary wave and so on. Especially the spin combustion model had been found in lot experiments. In order to enclose the cause of its formation, on the base of improving the heterogeneous SHS model, the combustion wave in a three-dimension cylinder had been study under different initial condition and different combustion system. Results showed the spin combustion model a weak flammability and a uns...
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