Manual metal arc ( stick) electrodes have a solid metal wire
core and a flux coating. These electrodes are identified by
the wire diameter and by a series of letters and numbers. The
letters and numbers identify the metal alloy and the intended
use of the electrode.
The
Metal Wire Core
works as conductor of the current that
maintains the arc. The core wire melts and is deposited into
the welding pool.
The covering on a shielded metal arc welding electrode is
called
Flux
.
The flux on the electrode performs many diferent functions.
These include:
●
producing a protective gas around the weld area
●
providing fluxing elements and deoxidizer
●
creating a protective slag coating over the weld as it cools
●
establishing arc characteristics
●
adding alloying elements.
Covered electrodes serve many purposes in addition to filler metal tothe molten pool. These
additional functions are provided mainly by the covering on the electrode.
3.2.4 Stick
（
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 for the correct selection of electrode.
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