An approach to predict the residual stress and distortion during the selective laser melting of AlSi10Mg parts

摘要

In the selective laser melting manufacturing, an accurate estimation of residual stresses and distortion is necessary to achieve high-quality specimens. During the manufacturing, the scanned layers are subjected to rapid thermal cycles. Steep temperature gradients generate residual stresses. Residual stresses can be detrimental to the proper functioning and the structural integrity of built parts. Therefore, it becomes particularly important to build a method to control the quality of the model. In order to realize the quality control of the SLM modeling, in this study, a three-dimensional model was developed for studying thermal behavior and residual stress during selective laser melting (SLM) of AlSi10Mg. Through the simulation, a prediction method for residual stress and deformation is found. To explore the relationship of the thermal effect between adjacent scanning trajectories, the calculated residual stress distributions are compared with independent experimental results. The effects of process parameters such as the laser power, scan speed, and scan strategy on the residual stress were also investigated. The results showed that the stress of the specimen gradually increased during the SLM process, caused by a heat accumulation effect.