Investigation on friction and wear in metal 3D-printed plane and textured meso-scale air journal bearings

An experimental setup is developed to examine the tribological performance of the meso-scale plane and textured air journal bearings. These bearings are fabricated using a novel texturing technique: metal 3D printing (additive manufacturing). First, plane and different-sized textured bearings (small: Tx1, medium: Tx2, and large: Tx3) are tested. The textured bearing, which offers minimal friction and wear, is proposed. Further, for the proposed textured bearing, the influence of texture distribution (full texturing and different partial texturing, viz. 0°–90°, 90°–180°, 180°–270°, 270°–360°, 0°–180°, and 180°–360°) is examined. These studies are performed at variable loading conditions (1N to 5N) operating in the speed range of 500– 25,000 rpm. Among various textured bearings, Tx1 performed best at variable rotational speed and applied loading. The partial texturing in 0°–180° is beneficial in the hydrodynamic regime at higher loading (4N–5N). Abrasive wear is dominant in the plane bearing, and adhesive wear in textured bearings.