Difficulties in Aluminum Alloy Processing and Their Solutions - Crack Problem

• Challenge: During the welding process of aluminum alloy, the generation of hot cracks is mainly due to the excessive shrinkage stress during the solidification of the molten pool, which exceeds the tensile strength of the weld. Hot cracks are often located at the center or root of the weld, and sometimes they may also appear in the heat-affected zone. 

• Solution: Design the welding structure reasonably to avoid excessive concentration of welds, so as to make the stress distribution more uniform; replace the single V-type joint with U-type or double V-type joints to reduce stress concentration; arrange the welding sequence reasonably to reduce the deformation and stress caused by welding; reduce the current and voltage, increase the welding speed to reduce the heat input; use aluminum-silicon alloy welding wires with higher silicon content to improve the crack resistance of the weld.