Work

Low friction glaze layer formation during lubricated dynamic pressure sliding of grade 250 flake graphite cast iron

Year: 2026

Type: article

Abstract: Evaluating scuffing resistance of new materials for reciprocating engine components can be achieved using dynamic pressure sliding. Surface species responsible for low friction behaviour observed prior to scuffing initiation in a Grade 250 flake graphite cast iron under dynamic pressure (8–62 MPa) sliding conditions experienced by a heavy-duty diesel engine top compression ring were evaluated. Lubricated reciprocating tribometer tests were performed in a polyalphaolefin base oil with temperature incremented to 250 °C to induce scuffing. Friction and contact potential measurements revealed a transition from mixed to boundary lubrication, followed by a period of low friction preceding scuffing initiation. Post-test surface analysis was conducted using a range of advanced microscopy techniques (Raman, FIB, STEM, EDX and EELS) and suggested a complex series of tribochemical reactions are responsible for formation and removal of phases such as siloxanes and ferrous oxides that lead to the initiation of scuffing.

Source: Tribology - Materials Surfaces & Interfaces

DOI: 10.1177/17515831261422305

Authors: John Walker, Timothy Kamps, Keith Paton

Institutions: University of Southampton, National Physical Laboratory

Language: English

Topic: Tribology and Lubrication Engineering

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,150

Funders: Henry Royce Institute, University of Oxford, Engineering and Physical Sciences Research Council