OPERATION
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MMA / Stick Electrode
•The arc is initiated by momentarily touching the electrode to the base metal.
• The melted electrode metal is transferred across the arc into the molten pool and
becomes weld metal.
• The deposit is covered and protected by slag from the electrode flux coating.
Flux Properties
● producing a protective gas around the weld area
● providing fluxing elements and deoxidizer
● creating a protective slag coating over the weld
● establishing arc characteristics
● adding alloying elements
Stick electrodes serve many purposes in addition to filler metal to the molten pool. These
additional functions are provided mainly by the various coverings on the electrode.
§4.1.3 MMA Welding Fundamentals
Electrode Selection
As a general rule, the selection of an electrode is straight forward, in that it is only a
matter of selecting an electrode of similar composition to the parent metal. However, for
some metals there is a choice of several electrodes, each of which has particular
properties to suit specific classes of work. It is recommend to consult your welding
supplier.
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