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These electrodes may have a rutile or basic coating. Basic coated
ones are only used
with DC (+). These electrodes have various types since they are
used for welding
martensitic, ferritic, austenitic, and corrosion-resistant steels
which compositions differ
from each other.
Stainless steel electrodes are classified in AWS A5.4, DIN 8556
and EN 1600. Symbols
indicate the composition of the weld metal. To prevent the formation
of chromium
carbides in the weld zone, these electrodes could be stabilized
with a niobium addition.
Some of the electrodes used in welding stainless and corrosion-resistant
steels have
a fully alloyed core wire, others could have alloying supplements
coming from the coating.
Where the majority of alloying elements come from the coating, the
electrodes are
called "synthetic".
When selecting stainless steel welding electrodes, the composition
of the base metal,
the ambient properties and temperatures, and the mechanical stresses
should be accounted for.
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