Simultaneous impact of build orientation on mechanical properties, geometrical measurements and surface roughness in material extrusion manufacturing

Purpose This paper aims to investigate how the build orientation simultaneously affects the tensile properties, geometrical measurements and surface roughness in material extrusion (MEX) produced parts. Design/methodology/approach An extensive experimental campaign was designed and carried out to elucidate the relationship between the rotation angles (input), defining the part orientation within the build volume, and the (output) variables measured by using 3D models reconstruction, roughness tester and tensile testing machine. Response surface methodology is used to capture the trend of each output relative to the input, while principal component analysis is used to identify relationships among outputs, providing a holistic understanding of how build orientation simultaneously influences mechanical properties, geometrical measurements and surface characteristics. Findings The study reveals that build orientation significantly affects nearly all output variables, with a pronounced dependency on the out-of-plane rotation angle. A key finding is the inverse correlation between mechanical strength and both geometrical measurements and surface roughness. This indicates that optimizing build orientation can enhance mechanical strength while minimizing geometrical defects. Originality/value This research, a newer addition to the existing literature, contributes to the field of additive manufacturing (AM) by offering an innovative analysis of the interaction between mechanical properties, geometric precision and surface roughness in relation to build orientation. It enhances the understanding of MEX processes and provides valuable insights into optimizing build orientation, thereby improving the competitiveness of AM over traditional production methods.