Mechanical constraint intensity effects on solidification cracking during laser welding of aluminum alloys

Effects of mechanical constraint intensity on solidification cracking behavior were investigated in single-side and double-side constraint conditions, respectively. A numerical model was developed to simulate the solidification cracking behavior during the laser welding process. The mechanical strain and accumulated crack-tip displacement were adopted to analyze the susceptibility of crack initiation and propagation, respectively. Results show that crack behavior is greatly influenced by mechanical constraint intensity. Stronger constraint intensity promotes the initiation of crack for both single-side and double-side constraint conditions. Higher constraint intensity tends to promote crack propagation in single-side constraint condition, and helps to suppress crack propagation in double-side constraint condition. (C) 2014 Elsevier B.V. All rights reserved.