Tribological tests of materials intended for roller bearing parts

摘要

This article presents the results of tribological tests of materials applied in roller bearing parts. The goal of tests was to determine the tribological properties of parts of a large-size cross roller bearing made from 6xxx-series aluminum alloy by means of metal forming methods and from 7xxx-series aluminum alloy by means of powder metallurgy methods. Tests were conducted using a T-05 tribological tester (ITeE - PIB) working in a block - ring testing system. The bearing's separator - ring (aluminum - aluminum) and separator -roller (aluminum - steel) pairs were selected for friction tests. The sample was an immobile block with a ray, made from EN AW-6060 or EN AW-7075 aluminum alloy, pressed with a constant force of F = 100 N to the countersample, which was a ring made from anodized EN AW-7075 aluminum alloy or 100Cr6 steel, rotating at a constant speed of 100 rpm. Friction and wear tests were performed over a friction path of 2000 m at ambient temperature (23°C) without lubricant, with the application of a nano-MoS2 powder layer, with the application of Tytalit grease, or with the application of a layer of nano-MoS2 powder and Tytalit grease. Nano-MoS2 powder was applied to the friction surface of the block by ball burnishing and Tytalit grease was applied to the friction surface of the ring immediately prior to testing. It was demonstrated that applying a nano-MoS2 powder layer to the block's friction surface and introducing Tytalit grease into the friction zone significantly reduced friction resistance in the tested friction pairs and thus reduced material wear.