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WELDING TECHNOLOGIES
AND EQUIPMENT
RESEARCH OF THE INFLUENCE Introduction common

of
One
the
OF THERMODYNAMIC, methods for joining stainless
steels is semi-automatic welding
PHYSICAL AND CHEMICAL with electrode wire in an inert
(argon) gas (MIG). Welding
PROPERTIES OF FLUX-OXIDES stainless steel in this way provides
high productivity and good weld
ON FORMATION OF quality. The main advantages
of the MIG welding process are
WELDED STAINS OF high productivity and high

quality of the weld. High
STAINLESS STEELS the absence of time losses
productivity is explained by

AT MIG WELDING as well as the fact that this
for changing the electrode,

method allows the use of
high welding current.
The disadvantage of this
method is the presence of a gas
cylinder and limited use in the
open air. Also, when welding in pure inert gas, despite for good protection of the welding zone
from exposure to ambient air, the formation of the weld is deteriorated, and the arc becomes
unstable.
The use of cored wire in this welding method can successfully eliminate these disadvantages.
However, the disadvantages of using cored wire are the formation of a large number of slags and
the high cost of cored wire.
These problems can be solved by using instead of flux-cored wire ordinary melting wire and
special powders [1–3], which are applied to the welded edges in the form of a paste, using a brush
or an aerosol can.
The disadvantages of this method include an increase in the complexity of the process, a
layer with an uneven thickness and width (when applied with a brush), high powder consumption
and the difficulty of automating the welding process.
The most effective and economical way to use these powders when welding in shielding
gases is the method of supplying special powders in the form of a gas-powder mixture [4-6],
which is obtained in the dispenser [7] by mixing the protective gas and powder. The gas-powder
mixture obtained in the batcher enters directly into the zone of the welding arc.
However, to date, the influence of the physicochemical properties of chemical compounds that can
be used in gas-powder mixtures on the size and shape of the welds obtained during MIG welding
with a batcher has not been studied. In addition, recommendations have not been developed
for the selection of chemical compounds based on optimal physicochemical properties, which
would ensure obtaining high-quality welded joints during MIG welding using gas-powder mixtures
sprayed from batchers into the welding zone.
The purpose of these studies was to study the influence of the physicochemical properties
of chemical compounds used in gas-powder mixtures, and to identify, on their basis, the optimal
requirements for these properties to obtain high-quality welded joints during MIG welding in an
inert gas environment.
EXPERIMENTAL APPROACH
The influence of the thermodynamic and physicochemical
properties of powder mixtures on the morphology of welds
was studied during MIG welding of stainless steel plates of the
CrNi1810 grade with a thickness of 4 mm and dimensions 60 x
150 mm.
The chemical composition of CrNi1810 steel is presented
in Table 1.
Powders of oxides (MgO, SiO2, Fe2O3, Cr2O3, TiO2,
Co3O4, WO3, Al2O3 CaZrO3 and BaZrO3) with particle size
distribution ≤ 100 μm were used as chemical compounds to
study the effect of their physicochemical properties on the
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