Sliding wear behavior of electrochemically textured surfaces under different lubrication regimes: Effects of curvature radius

• Published in: Wear Vol. 477; p. 203817
• Main Authors: Rodrigues, T.A., Costa, H.L., da Silva, W.M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 18.07.2021; Elsevier Science Ltd
• Subjects: Block-on-ring test; Boundary lubrication; Coefficient of friction; Curvature; Film thickness; Friction; Friction reduction; Frictional wear; Lubricants; Lubricants & lubrication; Lubrication; Maskless electrochemical texturing; Mathematical analysis; Medium carbon steels; Parameters; Sliding friction; Surface texturing; Texture; Texturing; Wear; Wear rate; Wear resistance; Block-on-ring test; Surface texturing; Friction; Wear; Maskless electrochemical texturing
• ISSN: 0043-1648; 1873-2577
• DOI: 10.1016/j.wear.2021.203817

Topography control has been applied as strategy to improve the efficiency of lubricated systems by introducing specific textures to the surface. Surface texturing can significantly affect the lubrication regime, improving the system's efficiency and reducing wear of moving parts. The present work shows the effects of different topographies produced by electrochemical texturing on lubrication regime, and its effects on the wear resistance of the textured surfaces. The lubrication regime was described using the ratio of the lubricant film thickness by the rms roughness of the surfaces (λ parameter). The tests used a block-on-ring tribometer. Samples and rings were made of AISI 1045 steel and SAE 4620, respectively. Lubrication regimes ranged from mixed to boundary for normal loads of 216.9 N and 315 N, respectively. The effect of texture position (inlet and outlet) and relative orientation of the texture patterns were studied. The rotation speed was fixed in 1500 rpm. The lubricant temperature was monitored during the tests. In the case of boundary lubrication, partially textured surfaces and fully textured surfaces presented a reduction in the friction coefficient of 23% and of 9.4%, respectively, when compared to a reference smooth surface. The friction coefficient reduced 12.6% when texture was positioned in the inlet and 23% when positioned in the outlet, when compared to the smooth surface. Moreover, total texturing reduced the wear rate by 15.2%. Linear relationships between wear volume and λ parameter, as well as between friction coefficient and curvature radius were found, confirming a strong relationship between lubrication regime, wear rates and real contact area (given by the curvature radius of the wear tracks). •Electrochemically textured surfaces were tested on block-on-ring lubricated test.•Surface texturing affects the lubrication regime improving the system's efficiency.•Friction coefficient reduced up to 23% when texture position was in the sample outlet.•Totally textured samples presented wear volume 15.2% lower than smooth samples.•A linear relationship between wear volume, λ parameter and curvature radius was found.