Experimental Study On Electric Pulse Processing Of Metal Materials

Processing of electric current pulse is an intricate interdisciplinary subject. But there is limitation because of its experimental condition, research methods and thinking models. Although a great deal of surveys and studies have been discussed the influence of pulse current on the metal solidification in recent years, there are very few researches on microstructure and properties of alloy and solid metal. It is no industrial application of electropulsing treatment in materials research. The effect and mechanisms of pulse current on metal material are not very clear at present. Influence of refinement mechanism of alloys, grain orientation of pure metals, distribution status of component and impurity and mechanical properties of metal by pulse current will be further studied.The scholars at abroad have done a lot of works in improving the toughness of tungsten heavy alloy. And plenty of work has been done in alloying, deformation strengthening, adiabatic shearing, numerical simulation and preparation process. There is not a very good enhanced technology which is fit for mechanical property of tungsten alloys penetrator. Heat treatment is mainly achieved bythermal effect. The annealing method exists with serious problems such as low efficiency, large energy consumption, polluting the environment and the oxidation of the specimen's surface. To overcome these disadvantages of traditional annealing process, we probe deeper into the new"annealing process" that is electric pulse treatment technology in this article. On the basis of studying copper and iron carbon alloy, we research deeply about the new processing technology for heavy alloy with the high current density electropulsing. This technology can replace the traditional annealing process.In this paper we update and optimize electric current, frequency, pulse width and loading time of the adjustable self-made pulse power equipment. We present the experimental scheme of pulse processing for metallic materials. The effects of copper, iron carbon alloy and tungsten alloy through a series of different parameters on pulsing current treatment are analyzed. Experiments show that recrystallization of copper has occurred under the current of 401A, frequency of 100Hz and loading time of 5 min. The temperature of recrystallization ranges from 200℃to 500℃. The recrystallization of iron carbon alloy takes place under the temperature of high frequency pulse treatment range from330℃to 520℃. The pulse current treatment can significantly reduce the initial temperature of recrystallization and increase the nucleation rate. Tensile strength of alloys decreases significantly after the pulse current treatment.The pulse current treatment has a certain promotion to plasticity of tungsten alloy with the loading time changing. As the frequency increase, the tensile strength increase slightly. The frequency, electric current and loading time can affect composition and structure of alloy at the same time.