Validation of Mechanical Layer Equivalent Method for simulation of residual stresses in additive manufactured components

Abstract

A challenge in the additive manufacturing process of laser beam melting of metals is the formation of residual stresses, which can cause large part deformations, when the part is released, lower the application range concerning tensile loads and provoke cracks. Due to the complexity and the interaction of different process parameters, the use of experimental studies for investigation is tedious and costly. An effective approach to analyze the effects is the numerical process simulation based on the method of finite elements. In this paper, the recently developed method of Mechanical Layer Equivalent for fast calculations of process induced distortions in laser beam melting is used to analyze the residual stresses during laser beam melting. For this purpose, small test samples have been generated additively and residual stresses have been measured by X-ray diffraction and compared to simulated values. The results show that despite the simplifications the model inhibits reliable prediction of residual stresses can be achieved.