Tribological analysis of TiN and DLC coated contacts by 3D FEM stress modeling and fracture toughness determination

Kenneth Holmberg, Helena Ronkainen, Anssi Laukkanen, Kim Wallin, Jari Koskinen

    Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientific

    3 Citations (Scopus)

    Abstract

    Surface coatings, like titanium nitride (TiN) and diamond-like carbon (DLC) coatings offer high wear resistance and low friction performance for a wide range of applications.By using new techniques such as modeling and simulation, the coating performance under load can be estimated and thus provide valuable information for the coating design and for the use of coatings in different applications.A three-dimensional Finite Element Method (3D FEM) model has been developed for calculating both the first principal stress distribution and the true stress components in the scratch test contact as the spherical diamond tip moves with increased load on a titanium nitride (TiN) and diamond-like carbon (DLC) coated steel surface.The three dimensional model is comprehensive in the sense that it considers elastic, plastic and fracture behavior of the contacting surfaces.Three main regions of stress concentration during the scratching action has been identified and analyzed. The first cracks to appear on the surface of a high-speed steel sample coated with a 2 µm TiN coating or 1 µm DLC coating are angular cracks on the edge of the scratch channel as the spherical diamond tip slides on the coated surface. This corresponds to the area of high two-directional stresses occurring at the side of the scratch channel.By identifying the location of the first crack and the crack density along the scratch channel and by using this as input data the fracture toughness of the coating can be evaluated.The influence of the coating thickness and elastic modulus on the stresses and strains generated during the sliding process is demonstrated.
    Original languageEnglish
    Title of host publicationApplied Material Research at VTT
    Subtitle of host publicationSymposium on Applied Materials
    PublisherVTT Technical Research Centre of Finland
    Pages311-328
    ISBN (Electronic)951-38-6312-3
    ISBN (Print)951-38-6311-5
    Publication statusPublished - 2006
    MoE publication typeB3 Non-refereed article in conference proceedings
    EventInternal Symposium on Applied Materials - Espoo, Finland
    Duration: 8 Jun 20068 Jun 2006

    Publication series

    SeriesVTT Symposium
    Number244
    ISSN0357-9387

    Conference

    ConferenceInternal Symposium on Applied Materials
    CountryFinland
    CityEspoo
    Period8/06/068/06/06

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    Keywords

    • ProperTune

    Cite this

    Holmberg, K., Ronkainen, H., Laukkanen, A., Wallin, K., & Koskinen, J. (2006). Tribological analysis of TiN and DLC coated contacts by 3D FEM stress modeling and fracture toughness determination. In Applied Material Research at VTT: Symposium on Applied Materials (pp. 311-328). VTT Technical Research Centre of Finland. VTT Symposium, No. 244 http://www.vtt.fi/inf/pdf/symposiums/2006/S244.pdf