基于电磁成形技术的金属材料焊接方法研究

发布时间：2018-01-07 22:15

本文关键词：基于电磁成形技术的金属材料焊接方法研究　出处：《沈阳航空航天大学》2017年硕士论文　论文类型：学位论文

更多相关文章： 电磁脉冲 搭接焊 射流 Kelvin波形

【摘要】：电磁成形技术是在微秒级的时间将电容组中的能量释放,利用线圈产生脉冲电磁力使金属工件成形的方法,属于高能率成形技术。电磁脉冲焊接是对电磁成形技术的推广应用,其原理是焊件以合适的压合速度、焊接角度压向被焊件,以期焊件与被焊件间形成原子键连接,实现常温下金属间焊接。此方法工艺复杂,对电磁成形机的技术参数、放电能力要求更高。电磁脉冲焊接在常温下实现同种或异种金属焊接,金属没有融化,可有效减少或避免金属间化合物的产生。本文对电磁成形放电回路系统进行分析,并对电磁脉冲焊接射流形成的条件和异种金属的焊接机理进行研究,应用Maxwell软件对不同放电电压下电流波形及电磁力进行仿真,采用该方法对TC4钛合金和3A21铝合金板材进行搭接焊试验,并对焊接截面进行金相组织检测及显微硬度分析,最后对电磁脉冲焊接的焊接机理进行研究。结果表明:焊接接合面呈不规则波浪形态,证明金属间为原子键结合,已实现焊接;电磁脉冲焊接方法可以实现异种金属板材的搭接焊,合适的压合速度、焊接角度即可在焊接区形成射流,并且射流的形成是实现搭接焊的必要条件;TC4屈服强度影响接合面波浪形态的波幅,TC4表面粗糙度影响波浪形态的波长;焊接区存在晶粒细化、滑移错动,使焊接区硬度高于基材硬度。由焊接试验及检测结果得出焊接界面波浪形态的形成是由于焊接瞬间焊件与被焊件间空气被压缩形成射流,射流中心与焊件间存在较大速度梯度,气流紊乱形成Kelvin滚旋,流体还未完全进入滚旋形式焊件与被焊件已经完成焊接,形成了波幅较小的初期Kelvin波形。
[Abstract]:Electromagnetic forming technology is a method to release the energy in the capacitor group at the time of microsecond, and to form the metal workpiece by using the electromagnetic force generated by the coil. Electromagnetic pulse welding is a popularized application of electromagnetic forming technology. The principle of electromagnetic pulse welding is that welding parts are welded with proper pressing speed and welding angle. In order to form the atomic bond connection between the welded part and the welded part, and realize the metal welding at room temperature, this method is complicated, and the technical parameters of the electromagnetic forming machine are also discussed. The discharge capacity is higher. The electromagnetic pulse welding realizes the same or dissimilar metal welding at room temperature, and the metal does not melt. It can effectively reduce or avoid the generation of intermetallic compounds. In this paper, the electromagnetically formed discharge loop system is analyzed, and the formation conditions of electromagnetic pulse welding jet and the welding mechanism of dissimilar metals are studied. The current waveform and electromagnetic force under different discharge voltages were simulated by Maxwell software. The lap welding tests of TC4 titanium alloy and 3A21 aluminum alloy sheet were carried out by using this method. Finally, the welding mechanism of electromagnetic pulse welding is studied. The results show that the welding joint is irregular wave shape. It is proved that the bonding between metals is atomic bond and the welding has been realized. The method of electromagnetic pulse welding can realize the lapping welding of dissimilar metal sheet, the proper pressing speed and the welding angle can form the jet in the welding area, and the formation of the jet is the necessary condition to realize the lap welding. The amplitude of TC4 yield strength affects the wave shape of the junction surface and the surface roughness of TC4 affects the wavelength of the wave form. There are grain refinement and slip dislocation in the welding zone. The hardness of welding zone is higher than the hardness of base material. From the results of welding test and testing, it is concluded that the formation of wave shape in the welding interface is due to the air compression between the welding piece and the welded part to form a jet. There is a large velocity gradient between the jet center and the welding piece, the Kelvin roll is formed by the turbulence disorder, and the fluid has not been fully entered into the rolling form of the welding piece and the welded piece has been welded. The initial Kelvin waveform with small amplitude is formed.
【学位授予单位】：沈阳航空航天大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG391;TG457.1

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