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A Model Study For The Electric Pulse Frequency Effects On The Solidification Behavior Of Al-5%Cu Alloy
[Full Text]
AUTHOR(S)
Qi Jingang, Li Yang, S.A Tukur, Zhao Zuofu, Wu Di, Dai Shan, Wang Jianzhong
KEYWORDS
Index Terms: model, electric pulse treatment (EPT), solidification structure, crystal rain, chill layer, Grain-refinement
ABSTRACT
Abstract: Electric pulse treatment (EPT) had recently proven to be an effective grain-refining technology; however, the quantitative understanding of the EPT mechanism is still unclear. This research work was based on electromagnetic field theory combined with the EPT mechanism proposed by Zhai et al. In this study, the two critical values of electro-pulse frequency under a certain pulse voltage were calculated; the crystal rain and the chill layer were formed during this non-equilibrium solidification. Thus, the electro-pulse frequencies and their influencing factors were modeled. The solidification behaviors were analyzed accordingly. The model exhibits that the time domain of EPM-induced grain refinement was found to be between the occurrence of crystal rain and the formation of chill layer. Furthermore, the proposed model was validated by the solidification structure changes of Al-5%Cu alloy.
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