Vertical Welding of Aluminum

Abstract

Electrosalg welding process for aluminum seems to be favarable to prevent the proosity in weld metal because of its small solidification rate. However, electrosalg welding process of aluminum needs the higher welding current than that of steel to prevent the lack of fusion.
This report describes a vertical welding process of aluminum by halfsubmerged arc, which can reduce lack of fusion with lower welding current compared with electroslag welding. The influence of welding conditions on the lack of fusion and porosity in weld metal using the consumable nozzle and graphite shoe is also reported and the following results are obtained;
1) Vertical welding process by half-submerged arc gives sound weld metal and no lack of fusion using electrode wires 2.4 mm and 3.2 mm in dia. with 900-1200 A welding current and 0.1-0.5 of flux ratio.
2) The suitable flux composition is NaCl 20 %-KCl 40 %-Na₃AlF₆ 10 %-LiCl 30 %.