Optimum vacuum solutions for electron beam welding

 

The electron beam as a heat source in thermal material processing has become indispensable in many industrial applications such as drilling, milling, perforating, melting or welding. Electron beam welding, in particular, has long since established itself in applications where high-precision, deep and distortion-free welds are required (see section „Applications“) and is used in a wide variety of industrial sectors. But what exactly is this joining process and why does vacuum play an important role?

What is electron beam welding?
In electron beam welding, a beam of strongly accelerated electrons is focused on a workpiece via adjustable magnetic fields. On the surface of the workpiece, the electrons release energy precisely at the point of impact, where they heat, melt and vaporize material. Generating the beam in the electron beam gun and the actual welding process in the welding chamber take place almost exclusively under vacuum at pressures in the high vacuum range (10^-3 to 10^-6 hPa). This is to prevent the electrons from being scattered by air molecules and enable trouble-free and loss-free focusing of the beam on the workpiece.

Advantages
Electron beam welding offers many advantages over traditional welding processes. It allows high welding speeds of up to 10 mm/s and welding depths of up to 300 mm to be achieved. And that’s not all. The ability to adjust beam parameters electrically also ensures precise real-time control and highly reproducible welding results.

Thanks to the high local energy density in electron beam welding, a wide variety of material combinations can be welded that are either impossible or extremely difficult to weld using conventional welding methods. Low heat input into the material surrounding the weld ensures minimal deformation of welded workpieces during electron beam welding and enables metals with high thermal conductivity to be welded. In addition, vacuum prevents unwanted oxidation of the welded workpieces.

Comprehensive portfolio for electron beam welding
Pfeiffer Vacuum offers a comprehensive portfolio for electron beam welding. This includes high and medium vacuum pumps for evacuating the welding chamber and the electron beam generator, pressure gauges for atmospheric to high vacuum pressure, valves and flange components for connecting vacuum components and leak detectors for locating leaks.