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Shielded Metal Arc Welding (SMAW)
Shielded Metal Arc Welding (SMAW) is defined as "an arc welding process in which coalescence of metals is produced by heat from an electric arc that is maintainedbetween the tip of a flux covered electrode and the surface of the base metal in the joint being welded." This process is commonly referred to as stick welding.

The electrode consists of a solidmetal core, which is covered by a metallic coating. The coatings composition is dependent on the type of electrode and welding polarity. It serves various functions during the welding process. Theseinclude; provide a shielding agent from the atmosphere which protects the molten pool; act as fluxing agents to cleanse the weld metal deposit, establish electrical characteristics of the electrode,provide a slag covering during cooling which can improve weld properties, enhance the ability to weld out of position, improve bead profile and appearance, and can add alloying elements to the weld toaffect mechanical properties.

SMAW is the most widely used welding process in the US and the world. The equipment cost is low and can be portable, it can be done in areas of limited access, it can bedone in all positions and it is a viable process for joining most metals and alloys. The low hydrogen (LH) mild steel electrodes are the most commonly used and represent up to 90% of the totalmarket. All stick electrode readily absorb moisture which will detrimentally effect weld quality. The LH being the most affected and should be stored in an electrode oven before use.

SMAW is typicallydone with DC current, either electrode positive or negative, but can also be used with AC current. Electrode positive produces higher penetration patterns and typically operate better, but electrodenegative results in the highest melting rate. Electrodes with high magnetic properties can experience arc blow with DC current and may be welded with AC setting. These include iron and nickel alloy...