Advanced Welding Processes: Technologies and Process Control

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Advanced welding processes
ranging from 0.025 to 300 mm. Some typical application areas are discussed
below.
Aerospace
The aircraft engine industry has used EBW extensively for the fabrication of
engine parts. A single engine, the Rolls-Royce RB211, utilizes nearly 100 m
of electron beam welds. [178] The principal applications include the joining
of thick-section stator assemblies in titanium alloys, compressor discs and
compressor rotor shafts. The use of EBW has been promoted by the requirement
for high integrity welds with low distortion and minimal thermal damage to
the materials.
Instrumentation, electronic and medical
The process has been used for the encapsulation of sensors and electronic
parts for electronic and medical applications. The materials used include
austenitic stainless steels for encapsulation and cobalt–chromium alloys for
fabricated hip joints.
Automotive
The narrow, deep penetration properties of the electron beam have been used
for the circumferential welding of gears to form complex clusters. The process
is also used for fabrication of transmission components such as gear cages.
Access and high weld quality are primary considerations in these applications
as well as the ability to weld finished components without distortion or the
need for post-weld machining operations.
Dissimilar metal joints
The most common production application of EBW to dissimilar metal joints
is the butt welding of high-speed steel blade forms to carbon steel backing
strip to form hack-saw blades. Although both laser and plasma processes
have been used in this application, EBW offers very high speeds of up to
10 m min –1 .
Copper alloys
Unlike laser processes, EBW may be used on a wide range of copper alloys,
and thicknesses up to 12 mm thick may be welded at 0.7 m min –1 with beam
powers of 10 kW. [179]