Tribological Properties of PLA 3D Printed at Different Extrusion Temperature

Abstract

Fused deposition modelling (FDM) 3D printing is widely used to manufacture prototype. To manufacture functional products with FDM 3D printing, several existing challenges have to be solved. Tribological behaviour of 3D printed parts has to be improved and optimised. In current study, friction and wear behaviours of 3D printed polylactic acid (PLA) printed at different extrusion temperature (190℃, 200℃, 210℃, 220℃, 230℃) sliding against steel disc were investigated. Pin on disc experiments that complies with ASTM G99-95a (2000) were conducted at a normal load of 15 N, and rotational speed of 150 RPM (0.69 m/s). Results showed that increasing the extrusion temperature resulted in a lower pin wear (specific mass loss) and higher friction coefficients. Pins printed at 190℃ showed to have the biggest pin mass loss and lowest friction coefficients, whereas pins printed at 230℃ showed to have the lowest pin mass loss and highest friction coefficients. This indicates the higher the extrusion temperature, the more capable it is for the deposited material to flow and homogenise with the neighbouring material which creates a flatter surface with less void between layers. Thus, effectively improving the interlayer bond making the FDM 3D printed part less susceptible to shear stress and delamination.