Experimental investigation of sheet metal forming of Aluminum 2024 using nanosecond pulsed Nd: YAG laser

Laser-induced shockwaves can modify the mechanical properties and plastically deform sheet metal in a process called Laser Shock Forming. This process has proven to be a viable forming method for both micro and macro scale fabrication of metal parts with complex geometry. In this research, the effects of laser intensity, sample thickness and overlapping ratio on the amount of deformation of Aluminum 2024 using Q-switched Nd: YAG laser operating at its fundamental wavelength of 1064 nm and pulse repetition rate of 1 - 5 Hz has been investigated. Through the experiments carried out, we observed that laser intensity and overlapping ratio had a positive effect on the size of the deformation whereby increasing any one of these parameters significantly increased the deformation observed as opposed to the sample thickness which had an inverse effect. By varying the sample thickness from 1 to 3 mm and laser energy from 2 to 6 J, we observed a transition from concave to the convex forming mechanism with a critical threshold or transition interval of 1.2-1.6 mm. We employed multiple regression analysis techniques to establish a relationship between the process parameters studied to the forming depth for the convex forming mechanism.