Surface characteristics underpinning fretting wear performance of heavily loaded duplex chameleon/PEO coatings on Al

Research output: Contribution to journalArticlepeer-review

  • External authors:
  • Mengyu Lin
  • Aneta Nemcova
  • Andrey A. Voevodin
  • Andras Korenyi-both
  • Tomasz W. Liskiewicz
  • Nicolas Laugel

Abstract

Duplex coatings comprising MoS2/Sb2O3/graphite layer burnished on top of plasma electrolytically oxidised AA6082 alloy enhanced fretting wear resistance against alumina and steel whilst reducing friction from 0.6…0.9 to 0.08…0.1 in dry nitrogen and humid air. Transitions to stick-slip (~3 m), partial slip (5-10 m) and gross slip (>10 m) showed an order of magnitude improvements over single-layer PEO coatings. In the latter mode, high initial contact pressures (1.1 GPa) with steel counterpart under oxidising atmosphere increased friction due to generation of Fe/Al/Cr oxides/hydroxides in the contact region, leading micro-cracking in PEO coating followed by fatigue damage of aluminium substrate. Reducing contact pressure <1 GPa, retained topcoat lubricating behaviour, high wear resistance and eliminated fatigue damage after 104 cycles.

Bibliographical metadata

Original languageEnglish
JournalTribology International
Publication statusAccepted/In press - 10 Oct 2020