A numerical model to study the temperature and residual stress profiles in hybrid additive manufacturing

Abstract

Recently, there has been an increasing interest in hybrid additive manufacturing (HAM) technologies to overcome the limits of conventional and additive manufacturing (AM) technologies. In the case of metals, HAM can be used to combine AM with forming operations. This concept can be applied in both the production of bulk and sheet metal parts. When sheet metal parts are taken into consideration, usually AM technology such as laser powder bed fusion (LPBF) and direct energy deposition (DED) can be combined with traditional forming operations. L-PBF is preferred when small details have to be applied to the metal sheet before undergoing the forming process. Thus, mass customization can be achieved by using the flexibility of the AM process, its ability to print complex geometries, and the speed of the sheet metal forming process. In this study, a numerical model was developed in order to analyze the influence of the L-PBF process on the metal sheet. The results show how the metal sheet is strongly influenced by the thermal input due to the deposition of the AM part. Moreover, the presence of residual stress can be observed within the metal sheet, which can result in distortion and create problems in the following forming step. The numerical model highlights also the more critical area, in which highstress concentration is observed.