Size-dependent plasticity in contact/friction: from discrete dislocation dynamics inside an asperity to statistical summation over asperities

Hengxu Song

Research output: ThesisThesis fully internal (DIV)

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The roughness of natural surfaces emerges in the form of surface asperities at length scales of micrometers or smaller, where plasticity is known to be size dependent: smaller is harder. However, existing contact/friction models, such as Greenwood-Williamson (GW) statistical model and its extended models, Persson's contact model for fractal surfaces, FEM models, either ignore plasticity or, at best, adopt size-independent plasticity. Therefore, there is a need to incorporate size-dependent plasticity into contact/friction models. The overall objective of this work is to gain a better understanding of contact/friction at micron/sub-micron length scales with an emphasis on the potential role of size-dependent plasticity.
Original languageEnglish
QualificationDoctor of Philosophy
Awarding Institution
  • University of Groningen
  • van der Giessen, Erik, Supervisor
Award date29-Nov-2016
Place of Publication[Groningen]
Print ISBNs978-90-367-9311-7
Electronic ISBNs978-90-367-9310-0
Publication statusPublished - 2016

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