Modelling stresses and fracture in thin coatings

Kenneth Holmberg, Anssi Laukkanen, Helena Ronkainen, Kim Wallin, Simo Varjus

    Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review


    The contact condition with a sphere sliding over a plate coated with a very thin coating is analysed. The dominant parameters for friction and wear performance are identified and the appropriate material parameters needed for controlling the tribological contact is proposed. A 3D Finite Element Model has been developed for calculating the first principal stress distribution in the scratch tester contact of a diamond spherical tip moving with increased load on a titanium nitride (TiN) coated steel surface. The model is comprehensive in that sense that it considers elastic, plastic and fracture behaviour of the contacting surfaces. Three main regions of stress concentration during the scratching action is identified. The loading mechanisms and the stress development in each of these regions is described. The first cracks to occur in a TiN coated steel plate sliding against a spherical diamond tip are due to the high stresses in the side-stress region and they are in an angular direction to the formed contact groove at the side edge of the groove. By identifying from a scratch experiment the location of the first crack and using this as input data can the fracture toughness of the coating be determined.
    Original languageEnglish
    Title of host publicationProceedings of the 6th International Tribology Conference, AUSTRIB '02
    Subtitle of host publicationFrontiers in tribology
    EditorsGwidon W. Stachowiak
    Place of PublicationPerth
    PublisherUniversity of Western Australia
    Pages651 - 656
    ISBN (Print)1-74052-087-4
    Publication statusPublished - 2002
    MoE publication typeA4 Article in a conference publication
    Event6th International Tribology Conference, AUSTRIB '02: Frontiers in tribology - Perth, Australia
    Duration: 2 Dec 20025 Dec 2002


    Conference6th International Tribology Conference, AUSTRIB '02


    • surface engineering
    • coatings
    • fracture
    • stress modelling
    • scratch tester
    • fracture toughness


    Dive into the research topics of 'Modelling stresses and fracture in thin coatings'. Together they form a unique fingerprint.

    Cite this