| Thermal explosion is a model of combustion synthesis. Compared with the self propagating model of combustion synthesis, thermal explosion has not been researched widely and deeply. So, through the research of thermal explosion, it does not only to help to understand the process of thermal explosion and learn how processing parameters affect the process, it also has great significance to enriching the combustion synthesis theory .Based on the MoO3-CuO-Al-Si system, the process of electrical thermal explosion for the fabrication of MoSi2/Cu composites was studied by creating a mathematical model. Also, the way to compute physical properties was proposed. Then the model was solved through the Direct Finite Difference Method (DFDM), a method of numerical calculation. Through the numerical calculation and analysis, the influence of some parameters( intensity of electric field, relative density, composition) on the process was researched .The results indicate that with the increase of MoSi2 contents, the electrical conductivity of system becomes more excellent, and the velocity of heating becomes higher. As the relative density increasing, the velocity of heating becomes higher too. After thermal explosion, the sample has the highest temperature in the middle, and along the direction of diameter and axes, the temperature becomes lower. Further more, the temperature gradient along direction of diameter is higher than which along direction of axes. It also displays that with the intensity of electric field increasing, the reaction time becomes shorter and the temperature after thermal explosion becomes higher.Finally, MoSi2/Cu composites were prepared by combustion synthesis process. MoSi2/Cu composites were studied by X-ray, SEM and EDS. The mechanics of formation the microstructure also were researched.
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