The influence of model orientation on achieved accuracy in multi jet fusion additive manufacturing.

The study analyses the effect of model orientation on the geometric and mechanical properties of PA12 parts produced by Multi Jet Fusion (MJF). Model orientation represents a critical factor affecting dimensional accuracy and overall print quality in additive manufacturing. In this experimental study, samples of identical geometry were manufactured with variations limited solely to their orientation along the X-, Y-, and Z-axes. Circularity, diameter deviation, and maximum tensile stress were evaluated. The results demonstrate that sample orientation significantly influences the dimensional accuracy of the manufactured parts. The most substantial deviations were observed for rotations about the X- and Y-axes. In contrast, orientation along the Z-axis exhibited only a minimal influence on the monitored properties. Mechanical testing confirmed stable tensile strength values, with no significant differences detected among the various orientations. The obtained data were used to develop a predictive model for estimating the geometric accuracy of a part as a function of its orientation within the build chamber. This model serves as a practical tool for designing and optimizing parts produced by MJF technology. Furthermore, it enables the selection of the optimal orientation to achieve the required accuracy and quality.