Dimensional Performance of As-Built Assemblies in Polyjet Additive Manufacturing Process

The additive manufacturing (AM) technology provides a unique opportunity to realize as-built assemblies, i.e., assemblies which can be fabricated as a whole in one build cycle. Some of the introduced challenges, however, are the design issues of these assembly structures and understanding the dimensional performance of the AM process to ensure proper mobility. While process improvement techniques have been proposed for dealing with individual additive components, it is also necessary to study the dimensional behavior of as-built assemblies compared to individual additive components. This paper studies and compares the dimensional performance of as-built assemblies with ordinary assemblies in which the components are fabricated individually and then assembled together. A design of experiment approach is applied to study the effect of assembly type and orientation on the final clearances. The results suggest that in addition to orientation factor, the type of assembly can also play an important role in the final clearance values. In addition, a different dimensional behavior exists in the as-built assembly structures compared to ordinary assemblies, i.e., clearances in as-built assembly tend to be smaller and also more uniform along the clearance profile.