Slovak University of Technology
Faculty of Material Science and Technology in Trnava
Machine Tools And
Devices For Special
Technologies
Electron beam machining
Material processing by electron
beam
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High intensity of electron beam energy (109
W/cm2),
High speed of electrons (1,6 108 m/s),
Small surface of impact (0,003 mm2),
Electrons in the crash with particular atoms
(molecules) of the base material transfer their
energy.
Depth of conjuction – depth in that electron
transfer completely their energy.
Material processing by electron
beam
Electrons are essentially bigger than photons.
More often crashes of electrons with air molecules.
Electron beam conductivity straight decreased with
distance that must be overcome by beam in the
air.
There is used vacuum room that conductivity will be
not decreased.
Principle of machining by
electron beam
Kinetic energy transmission in the impact to thermal
energy.
In the short time (s) the small volume of material
evaporated, steams are shoot out of becoming
crater remainder of melting.
Depth of conjunction is from some m to some
tenths m.
Principle of machining by
electron beam
Processing kinds by electron
beam
Cutting,
 micromachining,
 drilling,
 Marking, describing and engraving,
 welding,
 Thermal processing.
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Cutting by electron beam
Relative movement between beam and workpiece
is possible to securited:
Moving of the workpiece on the compound desk
– macromachining, trepanation of bigger holes,
Deflection of electron beam by deflection reel micromachining.
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Electron lithography – engraving of mask on the
workpiece surface before chemical processing
(electronic component)
Drilling by electron beam
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Small holes (5 m) with high accuracy (1m),
Holes above 0,25 mm – beam tipping
Bigger holes (above 2-5 mm) – trepanation
accuracy 0,025 mm,
They are used in production of filtre and riddles (big
number of small holes). Fast production of
accurately (dimensionally and positioning) holes.
Drilling by electron beam
number – 25600
diameter – 0,55mm
material –
anticorrosion
steel
Welding by electron beam
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Kinetic energy of impacted electrons is used for
material melting,
Possibility to chemical weld of active material in
the vacuum room,
Big depth of burnout,
Minimum thermal influenced area,
Needed continuous directing of beam energy
from 0 to maximum
Welding by electron beam
Device scheme
1 – processing room,
2 – compound desk,
3 – workpiece,
4 – electron canon,
5a – cathode,
5b – anode,
6 - Wehnelt electrode,
7 – covering,
8 – focusing reel,
9 – deflecting reels,
10 – connecting to vacuum
pump,
11 – electron beam,
12 – deflecting electron beam,
13 – input of high pressure
Example of device
Example of device
Example of device