First lets describe what the term fusion welding is so that when I say fuse you will understand what I am talking about. Fusion Welding is term for any welding processes that rely on melting to join materials of similar compositions as well as like melting points. A heat-affected zone is developed in the material, due to the high-temperature phase transitions inherent to these welding processes. Basically what that means is that the electrical current is creating friction
Arc welding uses an electrical arc to fuse the pieces of material along with filler material (welding rod). Arc welding involves attaching a grounding wire to the desired material or other metal surface that is to be welded upon. Another wire known as an electrode lead is placed on the material to be welded. Once that lead is pulled away from the material, an electric arc is generated. The arc then fuses the work pieces along with the filler material that helps to join the pieces.
Feeding the filler into the welding joint takes steady hands and an eye for detail. As the rod melts (carbon steel melts @ around 2500 degrees Fahrenheit), the welder must continuously feed the filler into the joint using small, steady, back-and-forth motions. These motions are what gives welds their distinctive appearance. Going too fast or slow, or holding the arc too close or far away from the material can create poor welds.
Shielded metal arc welding (SMAW or stick welding), gas metal arc welding (more commonly known as metal inert gas, or MIG, welding) and gas tungsten arc welding (frequently called tungsten inert gas, or TIG, welding) all exemplify arc welding.
These three common methods each offer unique advantages and drawbacks. Stick welding, for instance, is inexpensive and easy to learn. It's also slower and less versatile than some other methods. Oppositely, TIG welding is difficult to learn and requires an elaborate welding rig. TIG welding produces high-quality welds, however, and can weld materials that other methods can't.
