Nylon-aramid polymer composite as sliding liner for lube-less sliding bearing by fused deposition modeling

Aramid fibers are widely used in fiber-reinforcement due to their high fracture toughness, low coefficient of thermal expansion and high wear resistant. However Aramid fibers are available in the form of yarn and in powder state because of which it is unsuitable for most of the direct application. In this work, Aramid reinforced Nylon was used as a liner element for a sliding bearing, printed by Fused Deposition Modeling (FDM) and was tested for the effort needed to slide in comparison with the sliding-ball bearing. Spool with 3milimeter (mm) diameter containing Aramid 2% (weight) with Nylon was extruded and the sliding liner element was printed by FDM at full density with orientations of 0° and 90° to the travel direction. The surface finish of the contact surface was narrowed down to the least possible Ra value by optimizing the printing parameters including the road width, build plane and print temperature. The part with 0° orientation (along the travel path) with Ra of 0.6μm exhibited the least effort of 0.721 Newton (N). The polymer composite was also tested for its Tribological properties that exhibited a higher wear resistance of 0.3 gm/min. An improvement in the surface finish of the printed sliding element was achieved by optimizing the process parameter through Taguchi technique.