Orientation Controls Tribological Performance of 3D-Printed PLA and ABS

Additive manufacturing is rapidly growing in popularity for manufacturing parts with tunable mechanical properties. Recent studies show that mechanical properties can be achieved by controlling the layer orientation and build structure. In this work the effect of print orientation on tribological properties of 3D printed PLA and ABS are investigated. PLA and ABS samples are printed using fused deposition modeling (FDM) with three different print orientations. Tribological results show that variation in build direction relative to the sliding direction causes anisotropy in wear properties. The best wear properties are achieved with the samples printed where the layers remain orthogonal to the sliding direction. The coefficient of friction remains mostly unaffected by print orientation. PLA samples demonstrate significantly better tribological properties compared to ABS. Varying the sliding speed between the interacting surfaces also affects the wear properties of both PLA and ABS. The results suggest that optimizing the build orientation can improve the wear performance of additively manufactured thermoplastics. This enables an additional paradigm when designing for functionally graded materials.