A Review on Solidification Cracking of Welding Aluminum Alloys: Mechanism, Influencing Factors and Crack Resistance of Filler Metal

The crack-free welding of aluminum alloy is very significant in manufacturing lightweight components since aluminum alloys are susceptible to solidification cracking during welding. This work reviews the current understanding and advancements in the study of solidification cracking during welding aluminum alloys. Solidification cracks typically form near the end of the solidification process within the mushy zone, a region behind the molten pool where the material is partially solid and partially liquid. The complex high-temperature metallurgical behaviors in this zone play a crucial role in crack initiation. Research on the cracking resistance of filler materials has progressed significantly, offering valuable insights for mitigating cracks. The review covers the mechanisms of solidification cracking, influencing factors, and the cracking resistance of filler materials. It also highlights future research directions to deepen the understanding of metallurgical mechanisms and to support practical engineering solutions for controlling solidification cracks in welding aluminum alloys.