Frank G. Armao, The Lincoln Electric Co., Cleveland, OH
The question often comes up 'Isn't there one filler metal I can use for all my aluminum welding?' The answer, unfortunately, is no. However, there are basic rules for filler metal selection. First, know which aluminum alloys will be welded (Fig. 1). If all you know is that you have aluminum, that is not enough information to choose a filler metal.