Many people think of electron beam welding as a complex, expensive and even dangerous technology. There are several reasons for this: It requires a vacuum, the workpieces have to be precisely prepared and in addition there is the X-ray radiation. In times of laser welding, this may seem outdated. But is it actually true? Or does electron beam welding offer the possibility of a versatile and powerful technology?
With these and other questions in mind, Dr Schulze from Schulze-Consulting visited me in the Weld Lounge. Dr Schulze is an expert in the field of electron beam welding and, together with me as the WELDPROF®, would like to break down existing prejudices.
Replaced by the laser
Electron beam welding is a technology that has been used for many decades: it first appeared in industry in 1958. However, electron beam welding fell into oblivion in the 1980s as the laser made its way into industry.
At the time, laser technology was considered state-of-the-art and was well known to the public for its many applications in technology and medicine. From eye laser surgery to CD players – everyone had already heard of it. Today, the hype continues and the electron beam has largely been pushed out of industry. But what exactly is the reason for this?
How electron beam welding works
In electron beam welding, high kinetic energy hits the workpiece and melts it. To fully understand this process, we need to enter the world of atoms.
Normally, electrons are tightly bound to atoms. But, if sufficient energy is supplied, for example by a heated tungsten cathode, they can break away and move freely. With the help of electric and magnetic fields, the freed electrons are bundled into a beam and extremely accelerated by high voltage. During the process they can reach one to two-thirds of the speed of light. When the electrons hit the material, the enormous kinetic energy not only melts it, but even vaporises it. The whole process takes place in a vacuum, ensuring extremely clean and high-quality results.
At first glance, some features of electron beam welding seem complicated or even dangerous. Often it is assumed that the so-called evacuation time – the time it takes to create the required vacuum – could be an obstacle to the process. However, there is often special airlock technology to ensure that the vacuum in the working chamber is never interrupted. As a result, high speeds of up to six seconds evacuation time for a gear part can be achieved. For small parts, there is no need for an airlock chamber at all, as small working chambers can be evacuated within a few seconds.
Highly precise workpiece preparation
Since no filler material is added, each part must be prepared with great precision. At first sight, this also costs a lot of time and money. What is often not considered: The machine itself works extremely precisely and always fully automatically during the actual welding process. This not only ensures high-quality results, but also makes it possible to work very quickly.
X-rays are also a source of uncertainty when it comes to electron beam welding. In this Weld Lounge, we look at how this technology works, what it can do, but also at prejudices, advantages and disadvantages. If you would like to know more about electron beam welding, you can watch a short teaser video here:
You can watch the whole video on the WELDPROF YouTube channel.
Are you interested in other topics?
In general, every visitor to the WELDPROF® website can ask me specific questions via »Ask the WELDPROF®«. I am happy to answer them by e-mail or in one of my video formats. Interaction with interested parties from the world of welding and joining technology is expressly desired!