Welding Journal

When it comes to welding aluminum joints, root fusion is vital for strong, lasting welds. But it can be elusive. Root fusion in fillet welds is achieved when weld metal completely melts the base metal down to the joint root. Yet due to aluminum’s high rate of thermal conductivity, heat from the arc is transferred throughout the piece of metal rather than remaining concentrated toward the joint root, which deters root fusion. According to AWS D1.2/D1.2M:2014, Structural Welding Code — Aluminum, Section 3.6.3 ..