Biuletyn Instytutu Spawalnictwa No. 01/2012

L=1 mm, I=25 A L=1 mm, I=50 A L=1 mm, I=75 A
L=1 mm, I=100 A
L=2 mm, I=25 A L=2 mm, I=50 A L=2 mm, I=75 A
L=2 mm, I=100 A
L=3 mm, I=25 A L=3 mm, I=50 A L=3 mm, I=75 A
L=3 mm, I=100 A
L=4 mm, I=25 A L=4 mm, I=50 A L=4 mm, I=75 A
L=4 mm, I=100 A
L=5 mm, I=25 A L=5 mm, I=50 A L=5 mm, I=75 A
L=5 mm, I=100 A
Fig. 2. Image of welding arc in TIG method for arc length in range from 1 to 5-mm and current intensity
from 25 to 100 A; shielding gas: argon
Energy emitted in an arc column is mainly
scattered by conduction and convection.
Emission of electromagnetic radiation constitutes
10÷15% of energy supplied to an arc
[11]. Heat radiation, the source of which is a
body emitting high temperature, is characterised
by a continuous radiation spectrum. The
source of a continuous spectrum in the area
of a welding arc is mainly a liquid weld pool
[12]. The characteristic radiation of atoms and
ions in an arc is discrete. This type of radiation
is analysed in reference publications as plasma
radiation.
Plasma of a temperature contained in a range
between several eV and a few dozen keV
(in energy scale 1 eV = 11600 K) emits infrared
radiation, visible radiation, ultraviolet
radiation and X-ray radiation, which, due to
the mechanism of emission can be divided into
three basic types [14]:
NR 01/2012
BIULETYN INSTYTUTU SPAWALNICTWA
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