During GTAW, using DCEN approximately 30% of the heat is at the electrode and 70% of the heat is at the work piece. This creates deep penetration with a narrow melted area. DCEP is just the opposite. 30% of the heat is at the work piece while 70% is at the electrode. This creates shallow penetration and a wide melted area. For this reason, during DCEP welding the size of the electrode should be increased to accommodate the increase in heat input to the electrode. However, DCEP is seldom used with the GTAW process because the heat is concentrated at the electrode. AC welding cycles between DCEN and DCEP. AC is normally used in lieu of DCEP welding because you get the benefits of both.


Both the SMAW and FCAW process do not react in this manner. That is, I don’t believe you see a change in heat input to the electrode and work piece the way you do during GTAW. For these processes, current use is dependent on the flux that is used. For example, 6010 has a cellulose flux DCEP is used with these electrodes. When DCEN is used you will see more spatter and the metal spatter and the metal that is transfer will be large drops like globular transfer in GMAW. 6010 should produce a spray like transfer (this is the case when welding using DCEP). On the other hand, 6012 will be more stable with less spatter when DCEN is used. This electrode has a Rutile, Lime flux.

FCAW is a combination of SMAW and GMAW. The type of transfer depends on the type of flux that is used along with current and voltage.