Laser welding is a viable method of joining aluminium alloys. The input
parameters employed in the welding process have a significant impact on the weld
quality. There are several parameters that influence weld quality, however, describing
their relationship with weld seam characteristics is challenging. This study uses the
Taguchi approach and particle swarm optimization (PSO) techniques for improving the
weld quality in an Al 2024 lap joint to achieve a consistent and reliable joint. The
experiments are performed on a laser welding machine following an L9 orthogonal
array experimental design with peak power, scanning speed, and frequency as input
parameters. Here, breaking load, bond width and throat length are considered as the
responses. Experimentally a maximum breaking load of 1233 N and a minimum bond
width of 398.81 µm is achieved. The throat length ranged from 340.72 µm to 983.94
µm. Regression analysis is used to establish the relationship between the input and the
responses. The regression equations are utilized as the objective function in an
optimization problem. The crowding distance PSO is used to acquire the global optima.
Finally, the optimal process parameters for achieving the desired goals are presented.
Keywords: Aluminium alloy 2024, Design of Experiments, Laser welding, Particle Swarm Optimization, Taguchi method.
