Finite Element Model Updating of Laser Stitch Welded Structure

Abstract

The applications of laser stitch welding are increasing used in assemblies engineering products such as automotive structures due to its efficiency and re-liability in connecting a light weight material. In order to understand the vibration effect of the laser stitch weld towards the assembled structure, it is important to analyse its dynamic behaviour. However, they are relatively difficult to be analyse numerically as the laser stitch welded joints are found to be complex and have many uncertainties. This paper presents the investigation of finite element model for laser stitch welded structure. The reconciliation method of finite element model updating is used to improve the dynamic behaviour of the initial finite element model as close to experimental data. In this work, the finite element model of the laser stitch welded is developed by employing area contact model (ACM2) connector. Meanwhile, the experiment dynamic behaviour is obtained using an impact hammer and roving accelerometer with free-free boundary conditions. Later, the finite element model updating method is carried out in order to reduce the discrepancies of initial predicted models based on the experiment data. Based on the result, it was found that the ACM2 connector can be used to represent as la-ser stitch welds accurately by updating the most sensitive selected parameters.