ELECTRODE MELTING AND PLATE MELTING EFFICIENCIES OF SUBMERGED-ARC WELDING AND GAS METAL ARC-WELDING

The effect of process variables such as current, voltage, electrode extension, electrode diameter, etc., on the electrode melting and plate melting efficiencies of submerged arc welding (SAW) and gas metal arc welding (GMAW) has been studied. It has been shown that there is an increase in the electrode extension or a decrease in the voltage and electrode diameter. For the same welding parameters, the electrode melting efficiency is higher when the electrode is negative. A similar relationship was observed for GMAW. The results also indicated that the shielding gas in GMAW also had an effect on the electrode melting efficiency. The plate melting efficiency of GMAW increases with an increase in the welding current, voltage, and electrode diameter, and decreases with an increase in the electrode extension. For the same welding parameters, the plate melting efficiency is lower when the electrode is negative. For SAW there is an increase in the plate melting efficiency with an increase in the welding current and voltage. It was also observed that the plate melting efficiency was lower for the negative electrode. Although there was an indication of a decrease in the plate melting compared with similar effects in GMAHI: This decrease in plate melting efficiency did not seem significant. An attempt attempt has also been made to develop numerical models to predict the electrode and plate melting efficiencies from the process variables. © 1990 The Institute of Metals.