The evolution of subsurface deformation and tribological degradation of a multiphase Fe-based hardfacing induced by sliding contact

Journal article

Multiphase Fe-based hardfacing alloys, for example Tristelle 5183 Fe-21%Cr-10%Ni7.5%Nb-5%Si-2%C in wt.%, are extensively used for tribological applications, including valves, bearings and drive mechanisms, where two surfaces are unavoidably subjected to loaded sliding contact within engineering systems. In this study, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) were used to characterize, for the first time, the tribologically affected material induced by the self-mated sliding contact of HIPed Tristelle 5183. This provided novel insight into the deformation modes which permit the accumulation of the high levels of subsurface strain required for plasticity dominated (adhesive) wear in a commercial hardfacing. In the subsurface regions furthest from the sliding contact, plastic deformation is accommodated by deformation induced martensitic transformation to e-martensite and α0-martensite, twinning, the generation of planar dislocation arrangements (generated by planar slip) and the generation of dislocation tangles. Closer to the sliding contact, the subsurface becomes unstable, and nanocrystallisation driven by grain boundary mediated deformation mechanisms and crystallographic slip completely engulf the near surface microstructure. It is postulated that nanocrystalisation within the subsurface is a needed in order to accommodate the extremely high strains required in order to permit tribological degradation via plasticity dominated wear. The extrusion of metallic slivers via plastic ratcheting generates ductile shear cracksgoverned by plastic strain, and the failure of these slivers generates plate/flake-like wear debris

Authors: Carrington, MJ; Daure, JL; Utada, S; Ratia-Hanby, VL; Shipway, PH

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Elsevier
• Journal: Materials Science and Engineering: A
• Volume: 892
• Pages: 146023-146023
• Article number: 146023
• Publication date: 2023-12-18
• DOI: 10.1016/j.msea.2023.146023
• EISSN: 1873-4936
• ISSN: 0921-5093
• Language: English
• Keywords: Hardfacing; Wear resistance; Tribology; Materials science; Deformation (meteorology); Composite material; Metallurgy; Engineering; Degradation (telecommunications)