Welding Essentials: Questions & Answers, Second edition

What we do for ourselves dies with us. What we do for others and the world remains and is immortal.
Albert Pine
Today there are more than one hundred welding processes recognized by the American Welding Society (AWS). The previous chapters covered the most important and most frequently used welding processes. These represent the majority of welding man-hours and filler metal poundage used. However, there are still many specialty welding processes which make modern life possible. This chapter looks at these less common, but still essential processes. Unlike the previous process chapters, this is a survey chapter and does not prepare the reader to use these processes without further instruction. This overview will cover principles of operation, capabilities, applications, advantages and disadvantages.
How does electron beam welding work and what are its applications?
Electron beam welding, AWS designation EBW, uses a focused high-energy electron beam to make welds. A heated filament, much like those found in TV picture tubes, provides an electron source. In a vacuum, a high voltage (100 kV) accelerates these electrons away from the filament toward the anode in a vacuum. Most of the electrons do not strike the anode and continue on past it where they are focused into a tight beam by a magnetic lens. The kinetic energy these electrons acquired from being accelerated by the high voltage becomes heat when the electrons strike the work metal. Power densities in the range of 0.1 through 100 MW are possible...