Tribological anisotropy of selective laser sintered PA12 parts

Additive manufacturing techniques like selective laser sintering (SLS) of polymers are on the verge from a pure prototyping technique to producing small lot sizes, as it enables the production of highly complex components without a mould. The parts are build layerwise and therefore the resulting components exhibit specific characteristics like anisotropic mechanical behavior, porosity and a high surface roughness. As SLS enables the production of whole assembly groups in one building step without the need of assembly, a missing factor is the tribological interaction of these parts. The scope of this paper therefore is to identify the influence of the building orientation on the tribological properties. The resulting anisotropic behavior is presented under different loads and in comparison to specimens produced in a pvT-device to point out the influence of the inner structure and surface of the parts during the different stages of a tribological interaction.