Distortion prediction and compensation in selective laser melting

This paper presents a new approach for modelling additive layer manufacturing at component scale. The approach is applied to powder-bed selective laser melting (SLM) and validated, where the mechanical behaviour of macro-scale industrial components has been predicted and compared with experimental results. The novelty of the approach is based on using a calibrated analytical thermal model to derive functions that are implemented in a structural finite element analysis (FEA). The computational time for a complete analysis has been reduced from many days to less than three hours for a 3D blade component with a height of 80 mm. The induced distortion in SLM has been compensated for by modifying the initial geometry using FE predicted distortion. A newly developed distortion compensation method, based on optical 3D scan measurements, has also been implemented. The two distortion compensation methods have been experimentally validated. In summary, the research presented in this paper shows that the mitigation of distortion in SLM is now possible on industrial macro-scale components.