Empirical and Theoretical Analysis of Laser Transmission Welding (LTW) Plastics
N. Kumar, N. Kumar, A. Mondal and R.S. Sen
Laser transmission welding (LTW) is increasingly being used to produce plastic joints in medical equipment, food packaging, electronics, toys, automobiles and allied industries. In the present work LTW was performed with a Nd:YVO4 laser on polycarbonate (PC) and acrylic in lap joint configuration where the effects of three input parameters such as laser power, welding speed and laser frequency on weld quality on the ultimate load (UL) being studied. It was found that the welding speed has a most significant effect on the joint strength followed by laser power and then pulse frequency. In addition, to understand the joint strength of these laser welds at an early design stage, laser welds were modelled using LS-Dyna. The simulations were based on a 20 mm square laser weld and developed from the experimental data for the lap shear tests. The predicted load–displacement curves showed a close agreement with the test data.
Keywords: Nd:YVO4 laser, polycarbonate (PC), acrylic, laser transmission welding (LTW), lap weld, joint strength, simulation, LS-Dyna