【作者】 吴海波；

【导师】 杨雨生； 郭九生； 初红艳；

【作者基本信息】 北京工业大学 ， 机械制造及其自动化， 2001， 硕士

【摘要】 电磁成型是本世纪50年代以来发展起来的一种金属加工工艺，电磁成型是利用金属在强脉冲磁场中受力作用而使其发生塑性变形的一种高能高速成型方法。由于金属是在脉冲磁场中受力变形的，故也称为磁脉冲成型。它具有生产率高、节省材料和能源、无污染等优点，在汽车、航天、宇航、电子等领域得到广泛的应用。 本文做了如下工作： 首先，制定了实验方案。根据电磁成型的原理，采用了适于电磁成型实验的充放电设备，工装及材料。 本文运用电磁学原理，推导出椭圆工作线圈的磁感应强度矢量表达式并给出了其径向和轴向的分量的解析式。在此基础上编制了数值分析程序，可得到空间任一点的磁感应强度，由此可求出毛坯所受磁场力的分布规律，并用实验进行了验证。 其次，在大量实验基础上，对电磁成型工艺进行了研究，包括不同材料电磁成型性能的比较，不同放电电压对电磁成型的影响及气流的影响等。 对实验件断口进行了金相及电镜分析，分析了高速成型的微观机理。通过对铝合金与铜合金电磁成型实验件的断口进行分析，对这两种材料在高速变形条件下的具体变形机理进行了探讨，得出铝合金在动态变形条件下，其孔洞形核是第二相粒子所产生的，而黄铜的孔洞形核最主要是由位错聚集产生二次滑移所致。 另外，电磁冲裁是电磁成型应用的一个重要方面，本文进行了一系列电磁冲裁和普通冲裁的对比实验，分别得到了普通冲载和电磁冲裁的实验件，实验表明，电磁冲裁实验件断面质量较好，光亮带所占的部分达到90％以上，光亮带与断裂带的分界十分平整几乎没有毛刺，这是普通冲裁成型不能达到的。文中运用冲裁过程的理论，对试件的冲裁断面的形成进行了讨论。 最后，电磁装配工艺是电磁成型应用的一个重要方面，它使用螺线管线圈。为了对电磁成型进行深一步的研究，实验中使用了自行设计和制造的新型的电磁成型工装和电磁装配工装，收到了良好效果。更多还原

【Abstract】 Electromagnetic forming is a metal-processing technics developed since 1950抯. The method of electromagnetic forming is the forming of metal under the force caused by strong magntic pulse. It is also called magntic pulse forming. The technics has advantages of high production rate, material saving, no pollution and so on. It is widely used in the industries of automobile, aircrafts, and electronics.The work of this thesis is focused in the followings.Firstly, the experimental schemes are established. According to the theory of electromagnetic forming, the electric charging and discharging devices, equipment and materials suitable for electromagnetic forinig are employed.Using the principles of electromagnetism, the vector equations of the magnetic induction intensity of an ellipse-shaped coil is educed. The resolution equation of the hefts on the radial and axial directions is also established. On the basis of these equations, a numerical analysis program is written to calculate the magnetic induction intensity at a given point. The conclusion are proved by experiment.Secondly, Based on the extensive experiments, the technics of electromagnetic forming are studied. The study also includes the comparison of capability of different materials at electro-magnetic forming. Also it looks into the influence of different discharge voltage and airstream onto the electro-magnetic forming.Metallography and electronic microscope analysis are made to the section of tested materials. The microscopic mechanism of rapid Forming is analyzed. Through the analysis of the structures and section of aluminum alloy and copper alloy by the ductile deformation during electromagnetic Forming, the rapid deformation mechanism is analyzed. The study suggests that, under the dynamic deformation condition, the hole-shaped cores of aluminum alloy is caused by the second -phase particles, ~vhile that of copper alloy by the secondary slippage mostly due to dislocation congregation.Furthermore, electromagnetic punch is an important aspect of the applications of electromagnetic forming. The study in this paper carried out a series of comparison experiments on the electromagnetic punch and ordinary punch. Respectively, the work made experimental pieces of the electromagnetic punch and ordinary punch . The experiment suggests that2Abstractexperimental pieces of electromagnetic punch are better in section quality. The boundaries between the bright areas and the fracture areas are very clear and smooth. The bright areas makes up more than 90% of the total area, while the rest is the fracture areas. So the whole section is relatively smooth with very few burrs. The quality of the section of ordinary punch is no match with this. The research also discusses the formation of section of the experimental parts under cut process theory.Finally, electromagnetic assembly technics is another important aspect of electromagnetic forming. In order to make more research into the electromagnetic forming, in the experments, the new equipments of electromagnetic forming and electromagnetic assembly designed and manufactured by ourself are used. The usages of the new equipments suggest a success.更多还原