Introduction
Non-Arc Welding Processes
• Resistive heating, chemical reactions, focused
light and electrons, sound waves, and friction
can also be used to join materials
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Resistance welding
Oxy-Fuel Welding
Friction welding (&Solid State)
Laser and electron beam welding
Brazing and soldering
Plastics joining
Adhesive bonding
High Energy Density Processes
High Energy Density Processes
• Focus energy onto
a small area
• Laser
– CO2 gas: fixed
position
– Nd-YAG crystal:
fiber-optic delivery
• Electron Beam
High Energy Density Processes
• These processes focus the energy onto a
small area
Examples
• Laser - 0.004 inch weld on 1-inch thick
stainless steel sheet
• Electron Beam - 0.030-inch weld width on
0.5 inch thick steel plate
0.1.1.2.1.T2.95.12
Laser Beam Welding (LBW)
Laser
0.1.1.2.1.T3.95.12
High Energy Density Processes
Laser Beam Welding (LBW)
shielding
gas nozzle
(optional)
Laser beam
Plasma plume
Plasma
keyhole
Molten
material
workpiece motion
Keyhole welding
High Energy Density Processes
Focusing the Beam
Heat
treatment
Surface
modification
Welding
Cutting
Advantages
Weld penetration, mm
12
6 kW CO2
10
2 kW Nd:YAG
8
6
4
2
0
1
3
5
7
Welding speed, m/min
• Single pass weld
penetration up to
3/4” in steel
• High Travel speed
• Materials need not be
conductive
• No filler metal
required
• Low heat input
produces low
distortion
• Does not require a
vacuum
0.1.1.2.1.T4.95.12
High Energy Density Processes
Limitations
• High initial start-up costs
• Part fit-up and joint tracking are
critical
• Not portable
• Metals such as copper and
aluminum have high reflectivity
and are difficult to laser weld
• High cooling rates may lead to
materials problems
Electron Beam Welding (EBW)
EB Applications
0.1.1.2.1.T6.95.12
High Energy Density Processes
Electron Beam Welding (EBW)
Advantages
• Deepest single pass
weld penetration of
the fusion processes
– 14-inch-thick steel
• Fast travel speeds
• Low heat input welds
produce low
distortion
High Energy Density Processes
Limitations
• High initial start-up cost
• Not portable
• Part size limited by size of vacuum
chamber
• Produces x-rays
• Part fit-up is critical
• High cooling rates may lead to materials
problems