Abstract
High energy beam welding (EBW) is an advanced welding process which uses a high energy electron beam to make the metal in the weld zone form a molten pool to melt the material. The biggest advantage of EBW is the great precision weld. Since EBW is suitable for flat, vertical and angular welding, it is widely used in aerospace, military and electronic industries. EBW is a kind of efficient welding technology which pay attention to its production cost, low power consumption, wide application range and weld quality.
In this paper, we summarize the development history and basic principle of high energy beam welding (EBW) technology, analyze the advantages and disadvantages of EBW compared with other welding processes, analyze the application of EBW technology in the fields of aerospace, military, and electronics, and propose the development direction of EBW in the future.
Introduction
High energy beam welding (EBW) is a welding process that uses a high energy electron beam (EB) to melt metals in the weld zone. Since it is suitable for flat, vertical and angular welding, this welding process has been widely used in various fields such as aerospace, military and electronic industries [1].
The basic principle of EBW is to use energy deposition to form continuous welding technology. A high energy electron beam is focused and accelerated by a special welding gun energized by a high frequency power supply, and the electrons collide with the workpiece to generate heat, which melts the metal in the weld area and forms a continuous weld in the weld area.
In any welding technology, the welding process will influence the metallurgical structure and quality of the weld. Since EBW has a fast spot welding speed and a high precision welding process, it is the ideal welding technology in many complex welding situations.
Development history of EBW
The electron beam welding process was proposed by Becker in 1890, and was used by Von Browne in 1891 to get high voltage current discharge phenomenon. The development process of EBW is mainly divided into three stages: the first stage should start from 1950 to 1960, in this stage, the electron beam welding technology was mainly used in highly specialized fields such as aerospace, military and electronic industries. During this period, the electrostatic accelerators of several kilovolts were used as the main production method of the electron beam [2]. The second stage from 1960 to the 1980s mainly focused on the miniaturization and stability of the welding equipment, and accelerated the research of high voltage power supply technology and the development of electron gun miniaturization technology [3]. In the early 21st century, the development of electron guns and scanning devices, as well as the steady development of power supply technology, further improved the performance and speed of EBW technology [4].
Advantages and disadvantages of EBW
The advantages of EBW are as follows: 1) Welding speed is fast. EB rapid spot welding is suitable for welding parts with large gaps, with the welding speed of 1~2m/min. Due to the good stability of the EB beam under applied voltage, the welding speed can reach up to 20m/min. 2) High welding accuracy and quality. The focusing of electron beams makes the welding spot cross section and size uniform. In addition, the smooth weld of EBW eliminates the need for grinding after welding and punching before welding. 3) Low heat input and energy consumption. Compared with other conventional welding technologies, the power input of EBW is low, and the amount of deformation caused by the welding is small. 4) Wide application range. EBW welding is suitable for welding workpieces of various shapes, such as flat, vertical, horizontal and triangular.
But compared with other production processes, EBW technology has the following shortcomings: 1) The high cost of the equipment and the limited scope of application. EBW is an advanced welding technology, and the equipment and materials used in it are very expensive. In addition, due to the high cost of the equipment, the application range of EBW technology is also limited. 2) The operation requires high skilled workers. In order to operate EBW machine accurately and efficiently, professional skilled workers are required.
Application of EBW technology
Due to its excellent welding quality, high welding speed and low energy consumption, the application of EBW technology is becoming more and more extensive. It is mainly used in the fields of aerospace, military and electronic industries.
1) Aerospace. EBW is mainly used in the welding of aerospace fuel tanks, satellites and spacecraft. In the aerospace industry, EBW is most commonly used in aerospace fuel tanks. EBW has the advantages of high welding quality and low energy consumption. It can also solve the problem of strict requirements on fuel tanks, such as high and uniform welding quality, low welding deformation and welding defects. The welding of satellites and spacecrafts is also suitable for EBW. 2) Military. In the military industry, EBW is mainly used in weapon assembly or disassembly, bridge framework welding and structural welding. In addition, the high quality weld and low deformation of EBW can also ensure the accuracy of weapon assembling. 3) Electronics. EBW is mainly used for welding of components in communication and electrical equipment, such as waveguide hinges and waveplane. The high sealing performance of EBW can reduce the high cost of air conditioning and filter equipment, and improve the overall quality of electronic circuits.
Conclusion
In this paper, the development history, working principle and advantages and disadvantages of EBW technology are summarized. In addition, it can be found that EBW technology is widely used in aerospace, military and electronic industries. It is expected that in the future, EBW technology can further develop in the direction of further miniaturization, further cost reduction and higher welding speed.
References
[1] Li, W.H. et al. (2008), Microstructure and properties of electron beam welded Al-Si-Cu joints, Materials Science and Engineering A, Vol 491, No. 1-2, pp. 78-86.
[2] Zhao, H. et al. (2009), Performance analysis and optimization of electron beam welding gun, Journal of Materials Processing Technology, Vol 209, No.4, pp. 2266-2277.
[3] Li, Z. et al. (2011), Theoretical study on electron beam welding of high melting point intermetallic materials, Journal of Materials Processing Technology, Vol 211, No.2, pp. 413-417.
[4] Li, A. et al. (2013), Analysis on the Performance of Scanning Electron Beam Welding, Transactions of the China Welding Institution, Vol 34, No.2, pp. 3-7.
