Abstract
In order to prevent the weld metal of rusted, painted or oiled steel plate experiments of CO2-O2, CO2. Ar-O2 and Ar-CO2 arc welding were carried out using the electrode wires with various contents of deoxidizers, especially a fairly large amount of aluminum. As the result, it was experimentally concluded that an aluminum content over 0.35 per cent of electrode wire was effective to prevent the porosity in the weld metal of rusted, painted or oiled steel plate Moreover, the experiment on the influence of wind on porosity showed that the electrode wires containing aluminum were effective to prevent the porosity, even when gas shielded arc welding was carried out in the wind with 1 to 2 m/sec velocity, but it was not effective at more than 3 m/sec wind velocity.
