In the EBW weld, heat is generated by a beam of high energy electrons. These electrons come and continue a heat. The edges of the workpiece become fused together, forming a solid weld.
Major Factors in the EBW Process
Looking at the advantages and disadvantages, it is clear that two things are true: it’s a very effective type of weld and it’s a very expensive one as well. There is no doubt about that you may be wondering what is EBW welding?
First off, it is important to understand that the conditions necessary to create the proper weld in this process are quite stringent. Electron-beam welding can only be performed in a vacuum environment. In this environment there can be no gas that is present, as this can cause the beam to scatter or become distorted.
The vacuum environment also allows for high voltages to be used during the welding process. The higher the voltage, the greater the amount of electrons that can be released, which increases the heat. This helps to create better welds.
With all of these factors in mind, it is only logical that this is an automated type of welding process. It is always computer-controlled, and requires special training and some very expensive equipment to be able to properly generate such a weld.
How Does EBW Welding Work?
Because of the high technological level of this type of weld, it is only logical that it has been around for a short amount of time. That is true. In 1949, a German physicist created this type of weld. Karl-Heinz Steigerwald envisioned and was eventually able to create the first electron-beam welding machine. It took nine years before he had perfected the process, meaning that its first use in an industrial environment came in 1958. To understand this process, it is important to get a little physics lesson. So, bear with us for a moment.
In every element, whether it is hydrogen, oxygen, silver, or any other type of metal, the basic particle of the element is the atom. Inside the atom is the nucleus. Surrounding the nucleus are electrons. Depending upon what element you were talking about, the number of electrons can vary. For example, hydrogen has one electron that orbits around the nucleus. Oxygen has eight.
Each electron is extremely small and contains a negative charge. Each electron also has a certain amount of energy that it creates.
EBW frees these electrons from the atom and these electrons are used to create the beam, similar in many ways to how electricity is sent through a circuit. These free electrons are sent through a vacuum as part of a beam. As they are accelerated, they create friction with one another, leading to heat being generated. The higher the degree of acceleration, the narrower the beam, and the larger the amount of electrons, the higher the amount of heat that is generated. Thus, these three factors play a significant role in the welding process.
Because of the amount of heat that is generated and how perfect the conditions need to be to achieve that level, the process can only be conducted using a computer. It is fully automated, as introducing the human element into the process would only cause it to be corrupted.
Strong electrical fields created by the accelerating of these electrons is accomplished by increasing the level of power. The computer is able to increase the acceleration to a point that almost any value can be achieved.
The beam can then be narrowed through use of magnetic lenses to ensure that the weld is used exactly where it is desired. The amount of penetration can be maintained at any level, and the travel speed is easy to control as well because of the use of a computerized system.
Many of these systems also contain a sensor that allows the computer to detect if the penetration is either too deep or too shallow, or if it is creating too much or not enough heat. This will cause the computer to adjust the acceleration and width of the beam to compensate for the error.
Advantages and Disadvantages
Because of the heat that is generated, there are many advantages and disadvantages to this particular type of welding process. These include:
- Very little distortion.
- The ability to narrow the weld as well as narrow the zone that is affected by the heat.
- Creates a very tight weld that is evenly distributed.
- No filler metal is required.
- The materials that are needed for this type of weld can be quite expensive.
- There is a large amount of ex-rate irradiation produced.
- The production costs are producing such a weld are expensive as well.
What Are the Applications for EBW?
Because of the costs and conditions that are needed for this welding process, it is easy to see that this is not a type of welding process that can be used in almost any type of circumstance. The equipment is quite expensive and the conditions needed to create a vacuum for the beam limit when and where it can be used. However, there are many common industries where this is seen, such as:
- Automotive Manufacturing Industry.
In the automotive industry, the most common use for the EBW process is in the creation of the transmission. Complex parts need to be created and precision is extremely important. This welding process works quickly and makes distortion of the parts minimal, if not non-existent. The manufacturing process works quickly and is precise every time.
- Aerospace Components & Aircraft Engine Industry.
The same is true for its application in aerospace and aircraft production. The narrowing of the electron-beam allows for precise manufacturing of parts. This type of process also ensures that the durability of welds and part creation is as good as it gets. It’s impossible to replace a broken part on a satellite in space and you can’t pull over a plane if there’s a problem with the engine in flight. Thus, the creation of parts that can withstand prolonged use and still produce properly is essential.
- Bi-Metal Saw Blades.
In bi-metal saw blades, it is necessary to be able to combine two types of metals together so that they are closely interlocked and stable. Using an EBW weld has helped to create higher performance saw blades at a greatly reduced cost.
One thing you will notice about this type of process is that it is expensive to get started. This is not a cheap set of equipment at all. However, once implemented, it greatly reduces costs by being quick, accurate, and efficient. This is why it is rapidly becoming one of the most trusted and widely used forms of welding processes.