| Because of the simple preparation process, low energy consumption, small pollution and green environmental protection, zinc alloy is becoming a hotspot home and abroad and has been called as a new material of21st century, an ideal substitute of copper alloy. Many foreign countries, such as European Union, United States and Japan, have already owned quite mature technology in deformation zinc alloy research. These zinc alloy products are widely used in home appliances, construction, electronic communications, plumbing equipment, stationery, auto industry, etc. In our country, the deformation zinc alloy has not been widely used. Mainly because the research of production technology of deformation zinc alloy is just getting started, alloy exist inverse segregation and uneven structure, which makes it difficult to achieve extrusion forming. When replacing leaded brass, the cutting performance of zinc alloy is difficult to meet the processing requirements. Therefore, to develop a kind of deformation zinc alloy with good mechanical properties and cutting performance has important significance for the replacement of free cutting leaded brass.Due to its high efficiency, untouched stirring form, rotating magnetic field can change the melting heat transfer and mass transfer, thus the ideal flow field and temperature field can be obtained. Rotating magnetic field can effectively refine the grain and eliminate uneven distribution of alloy element and solidification structure. In this paper, the study of application of electromagnetic field in horizontal continuous casting are focused on, then the parameters of horizontal electromagnetic continuous casting of zinc alloy billets are optimized to provides a chance for producing high quality zinc and zinc alloy billets.This paper mainly research two types of Zn-Cu alloy:Zn-7Cu-0.25Mn, Zn-4.5Cu-0.2Mn-0.3Bi and a type of Zn-Al alloy:Zn-10Al-2Cu-0.4Mg. Studying how to via electromagnetic field to improve the micro structure and casting property, eliminate inverse segregation, overcome the phenomenon of bottom solidification speed is greater than the top caused by gravity and improve the quality of ingot surface. Results of the trial shows that rotating magnetic field can remarkably refine the solidification micro structure, diminish element segregation, eliminate uneven solidification structure and the phenomenon of the last freezing point deviated upward from center. For Zn-7Cu-0.25Mn, Zn-4.5Cu-0.2Mn-0.3Bi the optimized parameters are as follows:the current intensity is100A, the current frequency is30Hz, the casting speed is about3m/hr, under such parameters the surface segregation can get significantly reduced and microstructure of ingot is the most fine and uniform. For Zn-10Al-2Cu-0.4Mn, under magnetic field the dendritic Al-rich phase become granular, when the current intensity is80A, the current frequency is30Hz, the casting speed is2m/hr, pinholes are largely eliminated and microstructure get refined. |
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