Hydrodynamic performance testing of artificial textures with a novel Pin-on-Disc test method

Michael Pusterhofer ^* Michael Maier Raphael Scharf Florian Haumer Florian Grün

• University of Leoben, Leoben, Austria

In times of global climate change, the reduction of friction in technical applications is of crucial significance. Surface textures are one possibility to reduce friction in lubricated contacts. To provide a deeper understanding about the effects of surface textures on the tribological performance, this study analyzes wedge-shaped, textured lubrication gaps using a novel test rig with an in-situ lubrication gap height measurement. With this experimental Pin-on-Disc set up chevron-shaped and cylindrical textures with two different heights (ht=10 and 50µm) were tested under full film lubrication conditions. The pin was tilted in a very precise way to generate a convergent lubrication gap. The test results show the potential for friction reduction using textures. In general it can be stated, that the investigated textures show a clearly different behaviour than the smooth reference specimens. Mostly a friction force reduction could be measured for texture specimens, which also came along with a reduction in the lubrication gap height. The system runs still in full film lubrication, but a higher risk for coming into the mixed friction regime can be stated. Summarized, no univeral performance trend for single textures could be stated, it needs to be checked for each specific operation point, which texture provides the best enhancment.