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WELDING TECHNOLOGIES
AND EQUIPMENT

Fig. 3. Cross-sectional view of welds of CrNi 18-10 stainless steel 4 mm thick, welded using conventional technology (MIG)
and using gas powder mixture (A-MIG).

welded joints. Therefore, in accordance with the results obtained, for these indicators, oxides
having a melting point slightly higher than the melting point of the welded metal (1450 °C)
have the most favorable effect on the width and reinforcement of the welds.
Thus, the most effective oxides used as fluxes for MIG welding of CrNi18-10 steel are
oxides with a melting point (Tmo), which are in the range of melting points (Tmm) and 2000
°С, i.e. the following condition is met:
Tmm < Tmo < 2000 °C.
The results of studies of the effect
of the boiling point of oxides (Tbo) on
the morphology of welds of CrNi18-10
penetration coefficient (Kp) and power gain coefficient (Kh) of the morphology of welds). A high
steel are presented in Fig. 6 (graphs

correlation is observed between the
bulge coefficient (Kh) of the joints and
the boiling point of the oxides (Tho). A
weak correlation is observed between
the convexity coefficient (Kh) and the
boiling point of the oxides (Tho). The
polynomial approximating curve of this
dependence has a downward character,

no flux i.e., indicates a decrease in the convexity
coefficient with an increase in the boiling
temperature of the oxide.
Thus, the most effective oxides
Fig. 4. The values of the coefficients of penetration (Кр) and the
bulge (Kh) of the welds stainless steel CrNi 18-10 with a thickness used as fluxes during MIG welding of
of 4 mm, welded in accordance with the usual technology (MIG) and CrNi18-10 steel are oxides with an oxide
using a gas-powder mixture (A-MIG). boiling point (Tbo), which must satisfy

the following conditions:
Tbm <Tbo < 3000 °C.

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