**Jörg Schille 1,\*, Lutz Schneider 1, Stefan Mauersberger 1, Sylvia Szokup 2, Sören Höhn 2, Johannes Pötschke 2, Friedemann Reiß 3, Erhard Leidich <sup>3</sup> and Udo Löschner <sup>1</sup>**


Received: 27 February 2020; Accepted: 15 March 2020; Published: 20 March 2020

**Abstract:** This article features with the enhancement of the static coefficient of friction by laser texturing the contact surfaces of tribological systems tested under dry friction conditions. The high-rate laser technology was applied for surface texturing at unprecedented processing rates, namely using powerful ultrashort pulses lasers in combination with ultrafast polygon-mirror based scan systems. The laser textured surfaces were analyzed by ion beam slope cutting and Raman measurements, showing a crystallographic disordering of the produced microscopic surface features. The laser induced self-organizing periodic surface structures as well as deterministic surface textures were tested regarding their tribological behavior. The highest static coefficient of friction was found of μ<sup>20</sup> = 0.68 for a laser textured cross pattern that is 126% higher than for a fine grinded reference contact system. The line pattern was textured on a shaft-hub connection where the static coefficient of friction increased up to 75% that demonstrates the high potential of the technology for real-world applications.

**Keywords:** high-rate; laser texturing; high-power; laser; LIPSS; tribology; coefficient of friction
