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 µ₂₀ = 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.

Electrochemical machining (ECM) is a complex technology used to shape conductive materials, for example hard metals. The workpiece material is removed by anodic dissolution in aqueous electrolytes at extremely large current densities. Hard metals are non-homogeneous and consist of hard particles, e.g. carbides, embedded in a softer matrix formed by metals such as cobalt, nickel, iron or alloys. The final shape is determined by a custom made tool, the cathode, or by a new technique with a confined electrolyte jet (Jet-ECM). An optimisation of this process intents to ascertain detailed information about the influence of current and potential distribution, composition of electrolyte, electrolyte flow geometry, electrochemical behaviour and dissolution mechanism of the components and structure of the interface material/electrolyte. Experiments on WC6Co, a common hard metal consisting of WC particles with Co as a binder, are presented as an example