Characterization of hot cracking due to welding of high-strength aluminum alloys

The Spot-Varestraint Test was applied to assess the sensitivity of three aluminum alloys-A2024-T351, A2219-T87, and A7050-T6-to hot cracking from welding. The results indicate that the number of cracks increases with increasing augmented strain. This phenomenon occurs in both the fusion and the heat-affected zones. The number of thermal cycles also has a significant influence on the heat-affected zone; the number of hot cracks increases, especially in the heat-affected zone of the metal weld, with increasing number of thermal cycles. The compositions of these three alloys show that A2024 and A7050 have similar tendencies to be subject to hot cracking, greater than A2219. With increasing number of thermal cycles, the hot cracks show the same tendency, A2024>A7050>2219.