Influence of SiC polytypes on the mixed lubrication regime of self-lubricating composites containing in situ generated 2D turbostratic graphite

Fe-based self-lubricating composites, in which SiC particles act as precursors to in situ generated 2D turbostratic graphite as a lubricating phase, were produced via powder injection moulding (PIM). In order to study the precursor influence on the solid lubricant structure and properties, hexagonal (alpha) and cubic (beta) SiC polytypes were used. The composites were tribologically tested in dry and low-viscosity oil-lubricated conditions. Distinct precursors did not lead to significant differences between composites. However, due to the highly disordered graphite-rich tribolayer formation, they do provide lubricity, low friction coefficient, and high wear resistance, even in oil-lubricated conditions.

Automated summary

Fe-based self-lubricating composites with SiC particles as precursors were produced via powder injection moulding. Different SiC polytypes did not significantly affect the lubricant structure and properties of the composites. However, the composites exhibited lubricity, low friction coefficient, and high wear resistance due to the formation of a highly disordered graphite-rich tribolayer, even under oil-lubricated conditions.