1. Fusion Welding Processes
Shielded Metal Arc Welding

2. Fusion Welding Processes
Gas Metal Arc Welding

3. Fusion Welding Processes
Gas Tungsten Arc Welding

4. Fusion Welding Processes
GTAW Polarity: three different polarities in GTAW A. Direct-Current Electrode Negative (DCEN) B. Direct-Current Electrode Positive (DCEP) C. Alternating Current (AC)

5. polarities in GTAW process.

6. Fusion Welding Processes
Plasma Arc Welding

7. Shielding Gases
Both argon and helium can be used. Since it is easier to ionize argon than helium, arc initiation is easier and the voltage drop across the arc is lower with argon. Also, since argon is heavier than helium, it offers more effective shielding and greater resistance to cross draft than helium. Argon also has a greater oxide cleaning action than helium. These advantages plus the lower cost of argon make it more attractive for GTAW than helium.

8. Shielding Gases