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Binder-jetted parts require a subsequent sintering process to achieve the desired density and mechanical properties, resulting in anisotropic shrinkage and creep distortion. To compensate for this, accurate prediction of densification behavior is required. Although there has been research on optimizing the printing and sintering process to increase the reproducibility of Ti–6Al–4V parts, there is no accessible literature on modeling the densification behavior. In this study, the densification of binder-jetted Ti–6Al–4V samples is investigated experimentally through experiments with interrupted sintering cycles and dilatometry. Through these experiments, it is possible to determine the density changes throughout the entire sintering cycle as well as the anisotropic shrinkage of the printed samples. The results are used to calibrate phenomenological diffusion models for intermediate stage and final stage sintering capable of mapping the densification behavior throughout the entire sintering process. Due to experimental limitations, material parameters for grain growth are determined from experimental densification data. [Display omitted] • Phenomenological diffusion based densification model calibrated via experimental data for binder jetted Ti–6Al–4V parts. • Measurement of thermal expansion and anisotropy with dilatometry experiments. • Good agreement between sintering experiments in furnace and dilatometry experiments. • Determine material parameters for grain growth only through experimental data of densification. [ABSTRACT FROM AUTHOR]

[Display omitted] • To predict sintering deformation of MBJ parts, a calibrated material model is used. • Simulations' predictions are compared with experiments for two industrial-size parts. • Due to poor repeatability of MBJ, simulations are validated by a statistical approach. • Deformation of the part with smaller build height is predicted with ±1 mm tolerance. Sintering, as a post-processing step in metal binder jetting (MBJ), often results in distortion. Numerical simulations can predict sintering distortion and minimize costly trial-and-error experiments. The present paper implements a numerical approach based on a phenomenological model of sintering to capture the creep deformation during free sintering. To qualify and calibrate the material model for MBJ, metallographic studies, dilatometry experiments, and viscosity measurements are carried out instead of empirical models for viscosity and sinter stress. Using the calibrated material model, final sintering distortions are predicted in two industry-relevant parts. The reproducibility of MBJ products is illustrated by manufacturing seven specimens for each geometry, and a statistical method to evaluate the simulations' accuracy is suggested. The predictions have a good agreement with experimental results, particularly for specimens with a lower build height. As the build height increases in MBJ specimens, the number of interlayer gaps in the build direction grows, resulting in anisotropic densification. This causes a lower prediction accuracy under isotropic shrinkage assumption, especially in overhang areas. Consideration of anisotropic shrinkage and heterogeneous density distribution of green parts in sintering simulation is essential to improve the accuracy of sintering predictions for MBJ components. [ABSTRACT FROM AUTHOR]