Study of Laser Beam Welding of AA 2024 Using Taguchi Methodology

Aluminium alloys are widely used in aeronautic industry to produce light weight structures. Laser welding is used in modern applications and has many advantages over conventional welding techniques to join Aluminium alloys. Selection of process parameters is crucial in obtaining a good weld joint. This selection is specific to application and material. Aluminium alloys need special attention while welding with laser due to their physical properties. The objective of this study is to realize fine weld width, deep penetration joint with excellent mechanical properties. Hence, the influence of different laser parameters on the weld width in butt joint configuration is investigated using pulsed ND: YAG laser welding machine. The experiments are designed in Taguchi in such a way that the weld bead grows from conduction mode to keyhole mode. Process parameters (peak power, scanning speed, frequency, pulse width) are varied while keeping variables like focusing distance, shielding gas ad weld strategies are common for all the experiments. The material used is AA 2024. For all the investigated parameters, the weld width, cracks and pores on the weld bead are observed.