Sintering Model for Predicting Distortion of Additively Manufactured Complex Parts

The present study aims to provide understanding of the influence of external factors, such as gravity, during sintering of 3D-printed parts in which the initial relative density and cohesion between the powder particles are lower compared with those present in the green parts produced by traditional powder technologies. A developed model is used to predict shrinkage and shape distortion of 3D-printed powder components at high sintering temperatures. Three cylindrical shape connector geometries are designed, including horizontal and vertical tubes of different sizes. Several samples are manufactured by binder jetting to validate the model, and numerical results are compared with the measurements of the sintered shape. Simulations are consistent with empirical data, proving that the continuum theory of sintering can effectively predict sintering deformation in additively manufactured products. This work includes the assessment of the accuracy and limits of a multiphysics continuum mechanics-based sintering model in predicting gravity-induced distortions in complex-shaped additively manufactured components.