Electron beam welding and laser beam welding are fusion welding processes that are capable of making high quality welds in a wide range of metals, including those materials that are hard to weld. However, the two processes are not interchangeable. There are significant differences between the two that, both in the physics of each process, and how well each work depending on the materials involved, the speci!cations the part needs to meet, etc. Who hasn’t heard that question when consulting with a customer about the fabrication of a part? In some cases, the question has a simple answer, but often not, and the decision to use process A or process B comes down to a comparison of pros and cons, with cost as the thumb on the scale that tips the balance.

Choosing a Process

For precision welding requirements, the choice is usually between electron beam welding and laser beam welding. Sometimes other types of fusion welding, such as GMAW or GTAW, might be an option, but arc welding processes don’t have the penetration, small heat-affected area, pinpoint precision, and weld purity of EB and laser welding. Electron beams and lasers can be focused and aimed with the exceptional accuracy required to weld the smallest of implantable medical devices, and yet also deliver the tremendous amounts of power required to weld large spacecraft parts. Electron beam and laser welding are versatile, powerful, automatable processes. Both can create beautiful welds from a metallurgic and an aesthetic perspective. Both can be cost-effective.

But for all the similarities, electron beam and laser welding are wildly different from each other in terms of underlying physics and functional operation in the real world of the shop floor. It is in these differences that one particular process might have an edge for a particular application. Key to finding the characteristics that might make one more suitable than the other is understanding how electron beam welding and laser welding work.