Wear, vibration and acoustic emission characterization of sliding friction processes of coarse-grained and ultrafine-grained copper

Andrey V. Filippov, Sergei Yu Tarasov, Sergei V. Fortuna, Oleg A. Podgornykh, Nikolai N. Shamarin, Andrey V. Vorontsov

Research output: Contribution to journalArticle

8 Citations (Scopus)


Microstructural evolution of copper samples after equal channel angular pressing (ECAP) have been studied. The equiaxed ultrafine-grains first appeared after 4 ECAP passes and then occupied the bulk of the sample after 8 and 12 passes thus forming more homogeneous grain-subgrain structures. High values of ultimate tensile strength 653 MPa and microhardness (180 HV) have been achieved. Tribological testing under unlubricated sliding friction of as-annealed and ECAPed copper samples against a steel counterbody have been carried out with simultaneous registration of vibration acceleration (VA) and acoustic emission (AE) signals. Wear reduced with the ECAP pass number changed from 0 to 12. Structural evolution of metal in different structural states after sliding tests has been studied and its effect on wear and friction has been revealed. The ECAPed samples formed thick oxidized layers on their worn surfaces which then deteriorated by subsurface fracture. This subsurface cracking changed the sliding friction dynamics as well as the AE signal parameters. Correlations between the tribological system vibrations and AE signal parameters have been established.

Original languageEnglish
Pages (from-to)78-88
Number of pages11
Publication statusPublished - 15 Apr 2019



  • Acoustic emission
  • Copper
  • ECAP
  • Friction
  • Subsurface deformation
  • Ultrafine-grained
  • Wear

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Mechanics of Materials
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films
  • Materials Chemistry

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