Dr.-Ing. Lukas Oestringer

  • Postanschrift:

    Karlsruher Institut für Technologie

    Institut für Technische Mechanik

    Teilinstitut Dynamik/Mechatronik

    Postfach 6980

    76049 Karlsruhe

     

    Haus- und Lieferanschrift:

    KIT-Campus Süd

    Institut für Technische Mechanik

    Teilinstitut Dynamik/Mechatronik

    Geb. 10.23, 2.OG

    Kaiserstraße 10

    76131 Karlsruhe

Contact Mechanics and Stochastic Dynamics

oe_roughsurface
Sliding contact of two bodies with rough surfaces
test
Real contact area for two bodies with rough surfaces

Systems with friction are widespread in all kinds of applications. Unfortunatelly the precise simulative prediction of the resulting friction force in frictional contacts is still an unsolved task which has led to the developement of many empirical friction laws. Despite their great value for many practical and theoretical applications, a deeper insight into the actual contact situation and the corresponding friction force with its dependencies is necessary to improve technical systems e.g. with regard to energy efficiency and wear.

Early works on this topic by Greenwood & Williamson and Archard for the purely elastic and Bowden & Tabor for the purely plastic deformation case have at least led to a justification for Coulombs friction law. Their research efforts indicate that the real contact area is almost proportional to the normal contact force whereat this relation can be attributed to surface roughness in both load cases. By the additional assumption that the friction force is proportional to the real contact area Coulombs friction law can be justified.

Further investigations on the dry contact of two sliding metallic bodies depending on various physical parameters and sliding speed are performed. For this purpose, a thermomechanical model is developed and evaluated for different contact configurations considering the surface roughness of both contact bodies in particular. Subsequent investigations on the consequences of the calculated friction coefficient in the context of friction-induced vibrations are carried out.

Contact: Prof. C. Proppe, L. Oestringer

Publications


On the fully coupled quasi-static equations for the thermoelastic halfspace
Oestringer, L. J.; Proppe, C.
2023. Mechanics of Materials, 177, Artkl.Nr.: 104554. doi:10.1016/j.mechmat.2022.104554
On the influence of surface roughness on friction‐induced oscillations
Oestringer, L. J.; Proppe, C.
2021. Proceedings in applied mathematics and mechanics, 21 (1), e202100013. doi:10.1002/pamm.202100013Full textFull text of the publication as PDF document
On the calculation of a dry friction coefficient
Oestringer, L. J.; Proppe, C.
2019. Proceedings in applied mathematics and mechanics, 19 (1), Article: e201900407. doi:10.1002/pamm.201900407
Investigation of Vibrations Induced by Dry Friction in a Pin-on-Disk Experimental Set-up
Kapelke, S.; Oestringer, L. J.; Seemann, W.
2017. Proceedings in applied mathematics and mechanics, 17 (1), 375–376. doi:10.1002/pamm.201710157